2008 Design amp ManufacturingII

Spring 2004

MEMS Tiny Products

2008-spring-2003

Tunable microcavity waveguide fabrication process flow

front-view side-view (thrursquo waveguide)

1 RIE Si trench

2 Pattern Pt bottom electrode

3 Pattern PZT and anneal

4 Pattern Pt top electrode

2008-spring-2003 C Wong amp S Kim

Tunable microcavity waveguide12 fabrication process flow

front-view side-view (thrursquo waveguide)

2008-spring-2003

5 RIE SiO2

6 X-ray lithography of PMMAfor Cr mask

7 CF4 Si waveguide RIE

8 XeF2 isotropic release etch

Process Flow

Wafers

Deposition Lithography

Devices

Etch

Photo resist coatingPattern transferPhoto resist removal

OxidationSputteringEvaporationCVDSol-gelEpitaxy

Wet isotropicWet anisotropicPlasmaRIEDRIE

2008-spring-2003

Wet or dry

Wet Dry

Low resolution feature Size Low cost Undercut for isotropic Wider area needed for anisotropic wafer etch Sticking

2008-spring-2003

High resolution feature size Expensive Vertical side wall Avoid sticking

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Tunable microcavity waveguide fabrication process flow

front-view side-view (thrursquo waveguide)

1 RIE Si trench

2 Pattern Pt bottom electrode

3 Pattern PZT and anneal

4 Pattern Pt top electrode

2008-spring-2003 C Wong amp S Kim

Tunable microcavity waveguide12 fabrication process flow

front-view side-view (thrursquo waveguide)

2008-spring-2003

5 RIE SiO2

6 X-ray lithography of PMMAfor Cr mask

7 CF4 Si waveguide RIE

8 XeF2 isotropic release etch

Process Flow

Wafers

Deposition Lithography

Devices

Etch

Photo resist coatingPattern transferPhoto resist removal

OxidationSputteringEvaporationCVDSol-gelEpitaxy

Wet isotropicWet anisotropicPlasmaRIEDRIE

2008-spring-2003

Wet or dry

Wet Dry

Low resolution feature Size Low cost Undercut for isotropic Wider area needed for anisotropic wafer etch Sticking

2008-spring-2003

High resolution feature size Expensive Vertical side wall Avoid sticking

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Tunable microcavity waveguide12 fabrication process flow

front-view side-view (thrursquo waveguide)

2008-spring-2003

5 RIE SiO2

6 X-ray lithography of PMMAfor Cr mask

7 CF4 Si waveguide RIE

8 XeF2 isotropic release etch

Process Flow

Wafers

Deposition Lithography

Devices

Etch

Photo resist coatingPattern transferPhoto resist removal

OxidationSputteringEvaporationCVDSol-gelEpitaxy

Wet isotropicWet anisotropicPlasmaRIEDRIE

2008-spring-2003

Wet or dry

Wet Dry

Low resolution feature Size Low cost Undercut for isotropic Wider area needed for anisotropic wafer etch Sticking

2008-spring-2003

High resolution feature size Expensive Vertical side wall Avoid sticking

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Process Flow

Wafers

Deposition Lithography

Devices

Etch

Photo resist coatingPattern transferPhoto resist removal

OxidationSputteringEvaporationCVDSol-gelEpitaxy

Wet isotropicWet anisotropicPlasmaRIEDRIE

2008-spring-2003

Wet or dry

Wet Dry

Low resolution feature Size Low cost Undercut for isotropic Wider area needed for anisotropic wafer etch Sticking

2008-spring-2003

High resolution feature size Expensive Vertical side wall Avoid sticking

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Wet or dry

Wet Dry

Low resolution feature Size Low cost Undercut for isotropic Wider area needed for anisotropic wafer etch Sticking

2008-spring-2003

High resolution feature size Expensive Vertical side wall Avoid sticking

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Etching Issues - Anisotropy

-Structural layer-Sacrificial layer

mask An-isotropic

Isotropic

2008-spring-2003

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Etching Issues - Selectivity

Selectivity is the ratio of the etch rate of the target material being etched to the etch rate of other materials Chemical etches are generally more selective than plasma etches Selectivity to masking material and to etch-stop is important

2008-spring-2003

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Bulk Micromachining

KOH etches silicon substrate1048708 V-grooves trenches1048708 Concave stop convex undercut1048708 (100) to (111) 1048708 100 to 1 etch rate1048708 Masks1048708 SiO2 for short period1048708 SixNy Excellent1048708 heavily doped P++ silicon etch stop

2008-spring-2003

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Dry etching

1048708 RIE (reactive ion etching)1048708 Chemical amp physical etching by RF excited reactive ions1048708 Bombardment of accelerated ions anisotropic1048708 SF6 rarr Si CHF3 rarroxide and polymers1048708 Anisotropy selectivity etch rate surface roughness by gas concentration pressure RF power temperature control1048708 Plasma etching1048708 Purely chemical etching by reactive ions isotropic1048708 Vapor phase etching1048708 Use of reactive gases XeF21048708 No drying needed

sticktion2008-spring-2003

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

DRIE (Deep RIE)

10487081048708 Alternating RIE and polymer deposition process for side wall protection and removal1048708 Etching phase SF6 Ar1048708 Polymerization process CHF3Ar forms Teflon-like layer1048708 Only 9 years after the Bosch process patent 1994

2008-spring-2003

-15 to 4 μmmin-selectivity to PR 100 to 1

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Deposition processes

1048708 Chemical1048708 CVD (Chemical Vapor Deposition)1048708 Thermal Oxidation1048708 Epitaxy1048708 Electrodeposition

1048708 Physical1048708 PVD1048708 Evaporation1048708 Sputtering1048708 Casting

2008-spring-2003

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Thermal Oxidation

1048708 Silicon is consumed as the silicon dioxide is grown1048708 Growth occurs in oxygen andor steam at 800-1200 C1048708 Compressive stress1048708 ~2um films are maximum practically1048708 Simple easy process for electrical insulation intentional warpage etc

2008-spring-2003

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Thermal Oxidation

1048708 Oxidation can be masked with silicon nitride which prevents O2 diffusion

2008-spring-2003

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Chemical Vapor Deposition

Thermal energy to dissociate gases and deposit thin films on surfaces high productivity better step coverage low pressure (LPCVD) atmospheric pressure (APCVD) plasma enhanced (PECVD) horizontal vertical LPCVD pressures around 300mT (005 atmosphere) Moderate Temperatures 450oC SiO2 PSG LTO 580-650oC polysilicon 800oC SixNy ndash SiH4 + NH3 Very dangerous gases Silane SiH4 Arsine phosphine diborane AsH3 PH3 B2H6

2008-spring-2003

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Physical Vapor DepositionEvaporation

1048708 Evaporated metals in a tungsten crucible1048708 Aluminum gold Pt W1048708 Evaporated metals and dielectrics by electron-beam or resistance heating1048708 Typically line-of-sight deposition1048708 Very high-vacuum required to prevent oxidation load lock

E-beam evaporator

2008-spring-2003

Shadowing

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Physical Vapor Deposition ndash

Sputtering

1048708 Sputtered metals and dielectrics1048708 Argon ions bombards target1048708 Ejected material takes ballistic path to wafers1048708 Typically line-of-sight from a distributed source1048708 Requires high vacuum but low temperature

2008-spring-2003

Evaporation vs Sputtering

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Spin Casting

1048708 Viscous liquid is poured on center of wafer1048708 Wafer spins at 1000-5000 RPM for ~30s1048708 Baked on hotplates 80-500oC for 10-1000s1048708 Application of etchants and solvents rinsing1048708 Deposition of polymers sol-gel PZT

2008-spring-2003

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Deposition Issues - Compatibility

1048708 Thermal compatibility1048708 Thermal oxidation and LPCVD films1048708 Thermal oxidation and LPCVD vs polymers (meltingburning) and most metals (eutectic formation diffusion)1048708 Topographic compatibilitiy 1048708 Spin-casting over large step heights 1048708 Deposition over deep trenches-key hole

2008-spring-2003

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Deposition Issues - Conformality

1048708 A conformal coating covers all surfaces to a uniform depth1048708 A non-conformal coating deposits more on top surfaces than bottom andor side surfaces

Conformal Non-conformal Non-conformal

2008-spring-2003

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Photo 1 Cracking of sol-geldeposited PZT after 650C firing

Photo 2 Poor step coverage andhigh stress evolved at corner of a step

M Koo amp S Kim2008-spring-2003

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Lithography (Greek ldquostone-writingrdquo)

1048708 Pattern Transfer1048708 Appication of photosensitive PR1048708 Optical exposure to transfer image from mask to PR1048708 Remove PR - rarrbinary pattern transfer

2008-spring-2003

Top View Cross Section

Radiation

Mask

Photosensitive material

Substrate

Photosensitive material properties change only where exposed to radiation

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Photo resist

1048708 Spin coat phto-resist1048708 3000 ndash 6000 rpm 15-30 sec1048708 Viscosity and rpm determine thickness1048708 Soft bake -gtalignment -gtexposure1048708 Develop PR after exposure1048708 Hardbake

Positive Negative

a) Positive resist developer solution removes exposed material

b) Negative resist developer solution removes unexposed material

2008-spring-2003

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Photomasks

1048708 Master patterns to be transferred1048708 Types1048708 Photographic emulsion on soda lime glass (cheap)1048708 Fe2O3 or Cr on soda lime glass1048708 Cr on quartz (expensive for deep UV light source)1048708 Polarity 1048708 Light field mostly clear opaque feature1048708 Dark field mostly opaque clear feature

2008-spring-2003

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Types of Aligner

Contact Proximity Projection

2008-spring-2003

Reduction ratio 11Array of the same pattern rarr Stepper

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

IC manufacturing

This picture comes from an excellent introductory discussion about IC fabrication at icknowledgecom

3) Wafer sawn up on film frame

2) Wafer mounted on saw film frame

1a) Probed wafer

7) Trim and form

4a) Pick off good die

4b) dispense dic attach epo

xy

1b) Lead frame

Final package

6) Mold

14007

4c) Place die on the lead

frame

5) Wirebond from die to fra

me

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Double sidedAlignment

Mask alignment keysMask

Front side

Chuck

Wafer

Wafer alignment keys

Microscope objectives

Alignment marks

Features on wafer

Features on mask

Mask over wafer

Alignment marks used to register two layers wafer now ready to be exposed

2008-spring-2003

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Pattern transfer by lift-off

Subtractive Process

Photolithography

Additive Process

Pattern transfer by etching

Etch Deposit

Strip Resist

Pattern transfer by lift off

2008-spring-2003

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Bulk machining Square nozzle Pumping ink Piezoelectric ink jet

piezoelectric transducer

laminated metal plates

adhesive

Ink channel

diaphragm

Piezoelectric inkjet ndash how it works

Ink droplet

ink

Deflected diaphragm

Figure 42 Schematic illustrations of square and circular nozzles with their corresponding fabrication steps

2008-spring-2003

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

Ink jet printer ndash A quasi-MEMS case

1048708 Thermal jet by HP1048708 Superheat ink 250oC1048708 Peak pressure 14 MPa

2008-spring-2003

Refills in 50μs

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
• Slide 9
• Slide 10
• Slide 11
• Slide 12
• Slide 13
• Slide 14
• Slide 15
• Slide 16
• Slide 17
• Slide 18
• Slide 19
• Slide 20
• Slide 21
• Slide 22
• Slide 23
• Slide 24
• Slide 25
• Slide 26
• Slide 27
• Slide 28
• Slide 29
• Slide 30

2008-spring-2003

Thermal ink jet

orifice plate detailsubstrate detail (DeskJet 895C)

barrierheater ink

channel

• Slide 1
• Slide 2
• Slide 3
• Slide 4
• Slide 5
• Slide 6
• Slide 7
• Slide 8
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