Full-Field feature profile models in process control

SPIE (2005) Vol. 5755_16

TEA Systems, Inc.

Terrence E. Zavecz – TEA Systems Inc.http://www.TEAsystems.com

March 3, 2005

Full-Field feature profile models in process control

Contact [email protected]

(+01) 610 682 4146

SPIE (2005) Vol 5755 - 16 SPIE (2005) Vol 5755 - 16

mailto:[email protected]

March. 2005 Models for reticle performance Page -2-SPIE (2005) Vol. 5755_16

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• Introduction Physical Process Window description and Perturbations

• The Best Focus Feature Contour Formalization Removal of metrology and exposure systematic error Examples

• Duty Cycle• BARC• High k1 applications

• Full-Field Process Window Optimum Field Response

• With tool defocus removed• Depth of Focus & Focus Contours

• Application to Full-Wafer responses Formalization Addressing Film and Feature systematic Exposure tool artifacts

• Final Note Exposure artifact influence on the Process Window

• Conclusions

• Introduction Physical Process Window description and Perturbations

• The Best Focus Feature Contour Formalization Removal of metrology and exposure systematic error Examples

• Duty Cycle• BARC• High k1 applications

• Full-Field Process Window Optimum Field Response

• With tool defocus removed• Depth of Focus & Focus Contours

• Application to Full-Wafer responses Formalization Addressing Film and Feature systematic Exposure tool artifacts

• Final Note Exposure artifact influence on the Process Window

• Conclusions

Models for Reticle Performance


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Two-variable process window

• The number of un-Collapsed lines visible in a group were rated from SEM photos ranging from 0 to “7”

• Results are shown for an 80 nm feature width

mn

SN

n nm

M

m

FE

EaCD

10

0

BCD

Collapsed line


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Properties of the PW Surface

a00 Feature size at optimum dose and focus

a10 The dose sensitivity or change of features size with dose being inversely proportional to exposure latitude.

a20 Rate of change of dose sensitivity with dose

a02 Defocus sensitivity of the feature

a12 Dose & defocus coupling

mn

SN

n nm

M

m

FE

EaCD

10

0

C. Ausschnitt et al SPIE 5378 p38-47

C. Mack et al SPIE 5038-39

C. Ausschnitt et al SPIE 5378 p38-47

C. Mack et al SPIE 5038-39


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CD-SEM with PW CD vs Dose

CD vs Focus

Optimum Focus(for this case)

deFocus1. CD vs Dose is not

linear

2. Surface “fit” quality can vary!


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Why “Process Window” fit-quality varies?

• Primary disturbances causing CD Uniformity (CDU) variations grouped upon their sources.

Reticle Scanner Track & Process

Effective Focus

Wafer flatness

Device topography

Substrate

BARC coat

Resist Film coat

PEB Temp & Time

Develop

Exposure Dose

Slit Uniformity

Focus SetUp

Chuck Flatness

Up-Down Scan

CDUEffective Dose

Scan Linearity

CD’s

Flatness

Transmission


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Best Focus – Feature Contour

• Derive CD @ Dose & Best Focus

• Relationship functional for Feature Widths Side Wall Angle (SWA) Resist & BARC thickness Line Edge Roughness

01* 1

01

mn

SN

n nm

M

m

FE

Eam

F

CDBest Focus (for Critical Dimension or CD)

Set derivative = 0 & solve for “F”

CD @ Best Focus


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Dose Response of Best Focus (BF) & CD

• Feature vs Dose Will be near-linear if feature profiles are well resolved

• Best Focus vs Dose Slope should be ~0 if lens is near aberration free and

films do not influence focus response

Best Focus

Dose


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Example #1 – Duty cycle• 140 nm contacts

• 3 sets of pitch

• CD-SEM measured

p240

p550

p420

TCL=140nmcontact

Best Focus


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Example 2: BARC Performance

• The ARC 3 data has a lower CD vs dose, reducing it’s sensitivity to dose A greater target dose to obtain CD size of 80 nm A strong sensitivity of best focus to the dose

Best Focus Size_at_BF DoF DoseMean: 0.1230 79.2 0.5420 25Max: 0.1230 79.2 0.5420 25Min: 0.1230 79.2 0.5420 25

Best Focus Size_at_BF DoF DoseMean: 0.1040 79.2 0.5200 23.5Max: 0.1040 79.2 0.5200 23.5Min: 0.1040 79.2 0.5200 23.5

ARC3 at Best DoseNo ARC at Best Dose


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Example #3; Pushing the envelope

• Dose values are arbitrary• At 80 nm, we are driving the imaging capabilities of the lens• Note response of BF to scan & lens aberrations• Response is caused by wavefront asymmetry and results in

feature line edge asymmetry

Site 15 Site 30

Response for 80 nm, 193 litho process


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Consider the Process Window

• A CD-SEM based data sample of the process window


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Scatterometry Process Window Side Wall AngleWhat can we learn?

Dose= 18 19 20 21 22 23 24

Focus-0.24

-0.16

-0.08

0.0

+0.08

+0.16

+0.24

Process Window

• Exposures• 193nm litho process for 100nm

features– AT1100 scanner, 0.75NA with annular

illumination– 90nm gratings at 1:1 with full field

coverage– 240nm resist on 78nm Barc on Si

• OCD metrology: NI, rotating polarized light (Nano9030)

• diffractive optical metrology (scatterometry) - outputs spectral intensity changes of 0th order diffracted light intensity

Weir PW Software from TEA Systems


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Optimal BCD Image

• BCD values as estimated for the reticle• Across-field Focus and metrology errors removed by process• Note that these values include both reticle offsets and exposure/lens aberrations

BCD Contour Plot

X (slit) location (mm)

Y (

scan

) lo

cati

on (

mm

)

BCD Vector Plot

mn

SN

n nm

M

m

FE

EayxFR

1),(0

0

mn

SN

n nm

M

m

FE

EayxFR

1),(0

0

100 nm 1:1, 90nm TCD100 nm 1:1, 90nm TCD


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Optimum Field Response thru Dose

• BCD summarizes natural feature size response @ best Focus for each dose

• DoF computed when in control

Best Focus BCD4 (nm) DoF DoseMean: 0.0070 104.1780 18.0

Max: 0.0810 110.6640 18.0Min: -0.1570 100.6540 18.0IFD: 0.2380 10.0100 18.0

Mean: 0.0180 94.3450 0.0530 19.0Max: 0.0830 99.8950 0.0530 19.0Min: -0.1340 91.0560 0.0530 19.0IFD: 0.2170 8.8390 0.0000 19.0

Mean: 0.0330 84.4540 0.3560 20.0Max: 0.0940 88.9940 0.5970 20.0Min: -0.0740 81.4100 0.1710 20.0IFD: 0.1680 7.5840 0.4260 20.0

Mean: 0.1080 72.8100 0.6260 21.0Max: 0.9820 77.6260 0.6400 21.0Min: -0.1050 30.3330 0.5230 21.0IFD: 1.0870 47.2940 0.1170 21.0

Best Focus BCD4 (nm) DoF DoseMean: -0.0390 65.3970 0.0160 22.0

Max: 0.2880 70.2900 0.0210 22.0Min: -0.2800 61.7610 0.0110 22.0IFD: 0.5680 8.5290 0.0100 22.0

Mean: -0.0840 56.2490 23.0Max: -0.0320 59.1160 23.0Min: -0.1570 53.4410 23.0IFD: 0.1250 5.6740 23.0

Mean: -0.0570 46.2440 24.0Max: 0.0210 47.9520 24.0Min: -0.1340 43.7280 24.0IFD: 0.1550 4.2230 24.0


Max: 0.2880 70.2900 0.0210 22.0Min: -0.2800 61.7610 0.0110 22.0IFD: 0.5680 8.5290 0.0100 22.0

Mean: -0.0840 56.2490 23.0Max: -0.0320 59.1160 23.0Min: -0.1570 53.4410 23.0IFD: 0.1250 5.6740 23.0

Mean: -0.0570 46.2440 24.0Max: 0.0210 47.9520 24.0Min: -0.1340 43.7280 24.0IFD: 0.1550 4.2230 24.0


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Metrology & Process Independent CharacteristicsFocus

Uniformity

Depth of Focus Uniformity


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CD-SEM ReticleMEF+ = 4.3292

Optimized BCD from Wafer

Nanometrics ReticleMEF+ = 4.305813

Validation; wafer vs Reticle 5754-110 Poster5754-110 Poster


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BCD, TCD, SWA @ Best Focus/Dose


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BARC modeled wafer uniformityDusa et al. SPIE Vol. 5378-11 Dusa et al. SPIE Vol. 5378-11


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T3 (PR)

TCD

SWABARC

Derived variable distributions across the wafer

BCD


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BCD & TCD Size vs PhotoResist


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BARC Thickness & SWA


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Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 1.5- + - + - + -

+ - + - + - + Reticle Scan Direction

+

-

Scan Direction Artifacts


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Profile variation with Focus

Bottom CD

Slope

Top CD- + - + - + -

+ - + - + - +

Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5 Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5

- + - + - + -

+ - + - + - +

Scan direction

Process window

Lens After cleaningLens Before cleaning

See Poster: 5754-87See Poster: 5754-87


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Slope vs Dose across the slit

5 18 19 6


9 10 11 12

Up +ScanUp +Scan

Down -ScanDown -Scan


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Reticle Scan Removed

Bottom CD

Slope

Top CD

Reticle scan-stage component removed.

Provides view of lens perturbations

- + - + - + -

+ - + - + - +

Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5

- + - + - + -

+ - + - + - +

Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5



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Lens Slit Removed

Bottom CD

Slope

Top CD- + - + - + -

+ - + - + - +

Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5


- + - + - + -

+ - + - + - +

Focus = -1.5 -1.0 -0.05 0.0 +0.05 +1.0 +1.5

Lens aberrations removed.

Provides view of scan uniformity

Scan speed nonlinearity start/end of scan

- + - + - + -

+ - + - + - +

- + - + - + -

+ - + - + - +


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FR(x,y) @ Best FocusCD response after field focus

errors are removed.

TopCD

BottomCD

Slope

-Down + Up-Down + Up

Lens After cleaningLens Before cleaning-Down + Up-Down + Up


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A Note: Exposure artifacts & the model

• Be aware of scan artifacts such as stage scan direction perturbations

mn

SN

n nm

M

m

FE

EaCD

10

0

mn

m mFaCD

0


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Summary• Process Window surface models

The algorithm history extends through several formats Extended to Dose Response of Features independent of metrology & Field

focus Best Focus vs Dose

• Plot yields additional information on process response and extensibility

• Full-Field Process Window Provides the optimum feature response across the field Traceable directly to reticle measurements Can be extended to Depth of Focus and deFocus contours

• Full Wafer Response Implements Best Feature response of the Full-Field Process Window Models were shown for addressing wafer-systematic perturbations

• Scanner-specific field models shown in paper 5754-110 Systematic feature response perturbations

• Response to Film and and exposure tool artifacts Final Note

• Exposure tool induced perturbations can directly influence the accuracy of the process window calculation

SPIE (2005) Vol. 5755_16

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End of Presentation – Thank You

• Please visit posters: “Feature profile control and the influence of scan artifacts”

• 5754-87

“Models for reticle performance and comparison of direct measurement ” • 5754-110

Visit us at:

http://www.TEAsystems.comBARC

Uniformity


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SPIE (2005) Vol. 5755_16

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Background and additional slides


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(2)

Formalization of the Spatial Signatures

• - IFp(x,y): IntraField periodic signature reticle component and a systematic –within-wafer, periodic

component describing the scanner field (slit and scan signatures)

• - Wp (x,y): feature response variability This component is primarily a result of the “whole-wafer-at-a-

time” process steps, characteristic to resist and track.

• - DD (x,y): Die-to-Die variability variations in discrete scanning disturbances such as effective

dose, the incidental focus or scan direction.

• - r: the residual component

(1)•Feature Response to process disturbance “m” • is the sensitivity coefficient

Ref. 2: Mircea Dusa et al, “Intra-wafer CDU characterization … ”, Proc. SPIE (2004), Vol. 5378-11

Most complex signature


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Component Analysis of MEF

• Definition MEF = Mask Error Function

• In terms if IntraField Periodic SignatureIFp(x,y) = IFReticle+IFSlit, scan aberrations + IFeffective Dose,Focus + IFResist + IFflare,scatter +Ifscatter

MEF

Objective: Identify the MEF Components of IFp

Reduction) *CDmask (

CDresist MEF


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IntraField (IFp) Signature

• IFslit Perturbations

Lens aberrations Flare, scatter, proximity etc. Photoresist artifacts

• IFScan Reticle Stage Distortions: effective dose

• scan speed Effective Focus

• Stage pitch, yaw tilt• travel height-offset

• IFReticle

Effective feature width

Photomask Processing

rIFIFIFyxIF ticleScanSlitp Re),(

4

01 j

jj

n

ColumnScan ryaIF

IFslit= Lens Aberrations

4

0

)(n

nn

Rowsjslit xaxWLIF


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Lens-Slit Model, Row offsets

• Modeled offset of each slit position• Repeatability of each reticle scan’s travel• Contributing about 1 nm of noise to BCD

error budget

Focus offsets

4

0

)(n

nn

Rowsj xaxWL

•Lens-slit model is applied to every row of every field of the wafer. Results are summarized on the right.


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Right-side average


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Average Field


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BCD Raw Data


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Modeled BCD-RET across wafer


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Profile Response @ Best Focus (Before)

Bottom CDUP+ Scan Best Focus Size_at_BF DoF

Mean: 0.0580 157.5 0.1610Max: 0.3280 175.2 0.2070Min: -0.1170 146.5 0.1330IFD: 0.4450 28.7 0.0740

Down - Bottom CDScan Best Focus Size_at_BF DoF

Mean: 0.0300 158.6 0.2010Max: 0.5630 185.5 0.3870Min: -0.2120 143.5 0.1200IFD: 0.7750 42.0 0.2670

Top CDUp+ Best Focus Size_at_BF DoFMean: 0.0740 131.1 0.1870

Max: 0.1570 151.3 0.2600Min: 0.0000 113.3 0.0930IFD: 0.1570 38.0 0.1670

Top CDDown - Best Focus Size_at_BF DoF

Mean: 0.0320 129.8 0.2240Max: 0.1460 149.2 0.4000Min: -0.1010 100.6 0.1200IFD: 0.2470 48.6 0.2800

SlopeDown - Best Focus Size_at_BF DoF

Mean: 0.0030 87.6 0.2130Max: 0.0490 89.4 0.3530Min: -0.0330 85.5 0.0200IFD: 0.0820 3.8 0.3330

SlopeUp + Best Focus Size_at_BF DoF

Mean: 0.0240 87.8 0.2570Max: 0.0580 89.2 0.3270Min: -0.0220 86.8 0.1600IFD: 0.0800 2.4 0.1670

UP +Scan Down -ScanLens before cleaning


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Profile Response @ Best Focus (After)

Up + Best FocusBottomCD

at BF DoFMean: 0.0080 171.6 0.3850

Max: 0.0870 183.2 0.4000Min: -0.0710 163.5 0.3330IFD: 0.1580 19.8 0.0670

Up + FocusSlope Slope DoF_SlopeMean: 0.0180 87.6 0.2150

Max: 0.1190 88.7 0.4000Min: -0.0700 86.4 0.0470IFD: 0.1890 2.3 0.3530

Down - FocusSlope Slope DoF_SlopeMean: 0.0340 87.5 0.1480

Max: 0.1530 88.9 0.3470Min: -0.0520 86.5 0.0270IFD: 0.2050 2.4 0.3200

Down - FocusBCDBottomCD

at BF DoF_BCDMean: 0.0160 174.0 0.3350

Max: 0.0750 216.8 0.4000Min: -0.0400 157.3 0.1470IFD: 0.1150 59.5 0.2530

Up+ Best Focus Top CD DoFMean: 0.0010 142.5 0.3810

Max: 0.0710 159.0 0.4000Min: -0.0460 121.2 0.3130IFD: 0.1170 37.8 0.0870

Down - Best Focus Top CD DoFMean: -0.0240 144.2 0.3720

Max: 0.0640 173.0 0.4000Min: -0.1870 119.7 0.2330IFD: 0.2510 53.3 0.1670

Lens After cleaningUP +Scan Down -Scan


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Focus Uniformity


BottomCD

TopCD

Slope


BottomCD

Calculated fromTopCD

Slope

-Down + Up-Down + UpCalculated

from


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DoF Variation

TopCD

BottomCD

After Clean• Both features plot to the same scale• Note however there is a problem with the lower left

corner of the field with a shallow DoF Partially hidden here by the scale





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Lens-Slit Uniformity

• The piston BCD value of each columns yield a representation of the BCD perturbation caused by the lens.

• This is the Average Field• Variation show is caused by the 8 focus-

shifted fields• Slit contributes about 2 nm to error budget


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Average Field BCD Scan Profile

• Boxplot across Reticle Scan shown• Reticle & Wafer errors removed• The right-side (bottom) of the scan’s

mid-points has been averaged and transposed to the left-side (top) graph. Note the left-right pitch of the reticle-

scan’s travel accounting for approximately 1 nm of variation

Right-side average


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Slit Wobble

• Slit-wobble is contributing about 1.25 nm to error budget

• Tilt contributes 3 nm to budget


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IntraField Process Window

• W(x,y) = Feature Response located at (x,y) on reticle

• Process window reduction

• Site #8 Soft data-sport Easily corrected and handled

• Site #6 response Reticle Error Lens and/or scan aberrations

(MEF)

Site #8

Site #6

mn

SN

n nm

M

m

FE

EayxW

1),(0

0

mn

SN

n nm

M

m

FE

EayxW

1),(0

0


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Models for reticle performance• Introduction

• Formalized MEF derivation Influence of process and exposure Method of analysis

• Phase I Evaluation of effective focus & dose Full-profile response Characterization

• SEM, OCD

MEF calculation from SEM & OCD

• Phase II Full wafer response Process variation analysis ARC volatility Response wrt theory of CD vs Arc

• Summary• Process perturbation to feature profile error budget


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Focus uniformityDose = 20 21 (isofocal) 22 23


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Experimental conditions• Exposures

• typical 193nm litho process for 100nm features– AT1100 scanner, 0.75NA with annular illumination– 90nm gratings at 1:1 with full field coverage– 240nm resist on 78nm Barc on Si

• OCD metrology: NI, rotating polarized light (Nano9030)• diffractive optical metrology (scatterometry) - outputs spectral intensity changes of

0th order diffracted light intensity

• modeled grating parameters– bottom CD; – resist thickness (Tr) and Sidewall Angle (SWA)– bottom arc thickness (Tbarc)– mean square errror (MSE)

• Calculate BCD at optimum focus and dose Weir PW Software from TEA Systems Determine BCD surface across field with removal of focus errors

R R R R RTE TM TE TM( ) cos ( ) sin ( ) cos( ) sin ( ) cos ( ) 4 4 2 22


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Center slit response

• Determine Best focus for each site from 1st order derivative of each BCD vs Focus curve

mn

SN

n nm

M

m

FE

EayxW

1),(0

0

mn

SN

n nm

M

m

FE

EayxW

1),(0

0


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Analysis of Reticle-free CD’s

• Wafer 177 New metrology tool Fixed focus with selected sites

at +/-1% dF and +/-2% dF as shown

• Measured BCD, BARC, SWA & Photoresist

• 121 (11x11) points per field

Measured field sites

Layout with Focus offsets (in um) shown


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BCD as measured

Wafer damaged area

Bad site measurement


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BCD with Reticle errors removed

• BCD variation from film, focus and exposure variations


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BCD-RET vs PhotoResist

• RET has been removed

• Typical CD vs photoresist thickness curve Illustrates the Photoresist ablation from exposure & develope


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BCD-RET vs BARC

• This is for the field edges.


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SWA vs BARC

• As expected, BARC thickness has a strong influence on the profile


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PW spatial viewTarget

• 90 nm feature

• +/- 10% EL

Dose= 18 19 20 21 22 23 24

Focus-0.24

-0.16

-0.08

0.0

+0.08

+0.16

+0.24Focus Dose= 18 19 20 21 22 23 24

-0.24 7 7 7-0.16 7 7 7 7 7-0.08 7 7 7 7 7 7 7

0 7 7 7 7 7 7 70.08 7 7 7 7 7 7 70.16 7 7 7 7 70.24 7 7 7

Focus Dose= 18 19 20 21 22 23 24-0.24 7 7 7-0.16 7 7 7 7 7-0.08 7 7 7 7 7 7 7

0 7 7 7 7 7 7 70.08 7 7 7 7 7 7 70.16 7 7 7 7 70.24 7 7 7


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Focus-response Field Center

• Center-site of exposure for each dose


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Dose Response at best focus

• Optimum CD vs Dose curve for entire field• Focus errors across slit have been removed• Dose response is now linear

This assumes a flat field since focus is optimized at each individual site

CD vs Dose at Best Focus

BCD = -8.2515D + 256.98

60.065.070.075.080.085.090.095.0

100.0105.0110.0

18.0 18.5 19.0 19.5 20.0 20.5 21.0 21.5 22.0 22.5 23.0 23.5 24.0

Dose

BC

D3

(n

m)


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Center Slit: Focus & DoF Response • DoF = red

• Best Focus = blue

Feature @ ResidualsDose Site Best Focus Best Focus DoF Offset Slope Quadratic Sigma20.0000 13.0000 -0.0350 95.1576 0.2910 95.4140 14.9460 228.5280 1.945020.0000 14.0000 -0.0720 94.1776 0.1130 95.4230 37.0100 308.2390 1.391020.0000 15.0000 -0.0970 91.0807 0.3820 93.0710 40.2300 195.2410 1.452020.0000 16.0000 -0.0500 90.0853 0.0000 90.4680 15.2480 151.9880 0.992020.0000 17.0000 -0.0490 90.4063 0.4340 90.9160 21.3040 233.8330 1.721020.0000 18.0000 -0.0270 90.8636 0.5180 91.0340 13.3960 284.3020 2.7540

-0.120

-0.100

-0.080

-0.060

-0.040

-0.020

0.000

12 13 14 15 16 17 18 19

Location on slit

Bes

t F

ocu

s (u

m)

0.00

0.10

0.20

0.30

0.40

0.50

0.60

Do

F (

um

)

•Each site exhibits a unique value for optimum focus & Depth of Focus (DoF)

•Use Feature Size, independent of focus, to determine MEF

13 14 15 16 17 18


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BCD final (nm)

• Reticle values have been removed from the BCD metrology• Note residual of reticle image on gossly overexposed 24 mj column

Dose= 18 19 20 21 22 23 24

Focus-0.24

-0.16

-0.08

0.0

+0.08

+0.16

+0.24

Invalid data


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BCD Final Field



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Average Hitachi Field


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Nanometrics OCD Measured Reticle

• Nanometrics OCD Direct measurement of Reticle 400 nm patterns


Y (

scan

) lo

cati

on (

mm

)


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Reticle Scan Model

• Field-by-field Reticle-Scan Model

• Wafer model removed

6

1

),(m

mmxjj ycWLyxW


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Reticle-scan piston

• BCD Piston (offset) term for each modeled scan (column)

• Note the locations of the focus shifts and the corresponding shift in average field value Reaction may actually be more scan-

direction dependant


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Models for reticle performance• Introduction

• MEF Formaization Influence of process and exposure Method of analysis

• Phase I Evaluation of effective focus & dose Full-profile response Characterization

• SEM, OCD

MEF calculation from SEM & OCD

• Phase II Full wafer response Process variation analysis ARC volatility Response CD vs Arc

• Summary• Process perturbation to feature profile error budget


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BARC modeled wafer uniformity


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BCD vs BARC

• All exposures


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Residuals to modeled wafer


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Average Field BCD Slit Profile

• Boxplot across slit & Scan shown


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Row and Slit profile

• Nano-Day1 Data

• Slit & Scan signatures of tool

• Estimate of reticle errors Includes reticle plus focus & exposure perturbations

Slit Signature

Scan Signature


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Lens Slit Model – slit wobble

• BCD-RET data showing slit tilt or “wobble” during the scan sequence


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BCD Reticle-Scan Tilt & Curvature

• High BCD values at end of scan are most likely due to the slit-scan speed changes.

• Reticle-scanning is responsible for 1.7 nm of the BCD budget.

SPIE (2005) Vol. 5755_16

TEA Systems, Inc.

Layouts for Figures in Text


TEA Systems, Inc.

• W(x,y) = Feature Response located at (x,y) on reticle

• Process window reduction

• Site #8 Soft data-sport Easily corrected and handled

• Site #6 response Reticle Error Lens and/or scan aberrations

(MEF)

Site #8

Site #6


TEA Systems, Inc.

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