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Micro-Nano Mater ials
Character izat ion and I nspect ion- va uat on o ect r ca ropert es-
.
Dept . of Mechanical Science and Engineer ing
Nagoya Universit y, Japan
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
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Outline
1. The recent researches
-
. -
. crowave me o
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
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1. The recent researches
Evaluation of electrical properties of metallic
nanomateirals
2. Four-point probe method
3. Four-point AFM probe method
4. Microwave AFM method
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Introduction
Nanomaterials Low-dimensional materials whose crystal structures arrange
in zero-dimensional dot, one-dimensional chain or two-
, , ,
nanowhisker, nanorod, nanobelt, nanotube and nanofilm
The display of a plethora of electrical, optical, chemical and
ne- mens ona me a c nanos ruc ures
The important role in semiconductor industry or integrated
circuit (IC) of metallic nanowires
The evaluation of electrical conductivity (resistivity)
,
nanowires
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Introduction
Size-dependent of the electrical properties such asconductivity of metallic materials The electrical resistivity of metallic nanomaterials increases once the
. Grain boundary scattering and surface scattering are recognized to be
two most important mechanisms for size-dependent conductivity of
metallic nano-conductors at room temperature.
Electron-electron interactions, localization, and electron-phonon
interactions known as intrinsic contributions can also influence theconductivity of metallic nanomaterials, especially at extremely low
temperature.
only for dimensions approaching Fermi wavelength of materials (a few
nanometers), and they are not presently of practical concern.Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Conductivity measurement of metallic nanowires
- -
metallic nanowires, many experimental measurements have been
carried out since the beginning of 1980s.
Resistivity of metallic nanowires
AR
R: measured resistance
A: cross section area of the nanowirel: length of the nanowire
The values which should be measured directly include thegeometry, dimensions of the nanowires, as well as the
-
contact nanowires.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Geometry (cross-section shape) of nanowires
Four kinds of fabrications of the metallic nanowires used
for resistivity measurement
1. Nanowires deposited into pores of porous membrane templates
including polycarbonate membranes(1)-(3) and anodic aluminamembranes(4)
circular cross-sections which are preferred for their regularity.
2. Metallic nanowires deposited in the pre-manufactured trenches onsubstrates(5)-(7)
The trenches can be made by lithography or so-called spacer
technique.
The cross-sections of fabicated nanowires are always
.(1) Liu K et.al., (1998) Phys Rev B 58:14681-14684, (2) Toimil-Molares ME et.al., (2003) Appl Phys Lett 82:2139-
2141, (3) Bid A et.al.(2006) Phys Rev B 74:035426(1-8), (4) Zhang ZB et.al., (2000) Phys Rev B 61:4850-4861, (5)
Matrejean S et.al., (2006) Microelectron Eng 83:2396-2401, (6) Marom H et.al., (2006) Phys Rev B 74:045411(1-9),
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
ang e .a ., pp ys : -
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Geometry (cross-section shape) of nanowires
3. Nanowires deposited directly onto substrates by evaporation(8)(9)
The cross-sections are always trapezoidal and difficult to
4. The DNA-templated metallic nanowires(10)-(13)
-
by metallic particle clusters attached to the DNA templates
are always irregular, they were mostly assumed to be circularfor convenience.
The observation of cross-sections can be performed by various
types of equipments including transmission electron microscope(TEM), scanning tunneling microscope (STM) and atomic force
, .
(8) Huang Q et.al., (2009) Appl Phys Lett 95:103112, (9) Hinode K et.al., (2001) Jpn J Appl Phys, Part 2
40:L1097-L1099 (10) Braun E et.al., (1998) Nature 39:775-778, (11) Richter J et.al., (2001) Appl Phys Lett
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
78:536-538, (12) Richter J et.al., (2002) Appl Phys A 74:725-728, (13) Keren K et.al., (2002) Science 297:72-75
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Measuring the dimensions of nanowires
-
(length and cross section area)
fabrication technologies, the average cross-section areas also
can be estimated by calibration measurements(9),(14),(15).
The average cross-section area
l
R
A
d
/
d
l: length of the nanowire
R: measured resistance: resistivity of the nanowire
T: temperature
The length of nanowires under testing ranges from severalmicrometers to hundreds of micrometers, which can be steadily
.
(14) Steinhgl W at.al., (2005) J Appl Phys 97:023706(1-7),
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
. ., -
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Measuring the resistance of nanowires
Nanowires tested in the same substrate or trenchwhere they are synthesized
The probes can be connected to the nanowires directly or to
e ec ro es epos e on e nanow res.
The micrograph of silver nanowireunder four-point probe measurement (8)*
The micrographs of the microslit stencil-assisted nanowire and electrodes(16)**
(16) Vazquez-Mena O et.al., (2008) Nano Lett 8:3675-3682
* Reprinted with permission. Copyright 2009, American Institute of Physics
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
** Reprinted with permission. Copyright 2008, American Chemical Society
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Measuring the resistance of nanowires
Free-standing nanowires Some drops of solution containing the
wires on a SiO2 substrate Creation of
-
wires
Deposition of the electrodes
Subsequently place of the wires on topThe micrograph of nanowire
connected to four electrodes(2)*
DNA-templated nanowires
The DNA molecules that can be stretched
and connected to electrodes by molecular
combing before the metallic nanowires
The scheme of assembling DNA-templated**
*Reprinted with permission. Copyright 2003, American
Institute of Physics
** Re rinted b ermission. Co ri ht 1998, Macmillan
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
me a c nanow re w e ec ro es Publishers Ltd: Nature
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Determining the grain size of nanowires
In order to quantify the grain boundary scattering, the grain
,
can be done by various microscope and X-ray diffraction
method(1),(4),(6),(7),(17),(18).
(17) Durkan C and Welland ME, (2000) Phys Rev B 61:14215-14218
. ., -
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1. The recent researches
2. Four-point probe method
The most common and effective method to
measure the resistivity of metallic nanowires
3. Four-point AFM probe method
4. Microwave AFM method
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The advantage of four-point probe method
Two-point probe system
In micro-scale or nano-scale, the contact resistance between
device under test (DUT) and the probes always becomes
innegligible due to the extremely small contact area.
DUTwcmm 22/ RRRIVR
m
Rm: Measured resitance
Rc: Contact resistance
Sketch of the two- E uivalent circuit of the
w
RDUT: Resistance of DUT
point probe system two-point probe system
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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The advantage of four-point probe method
Four-point probe (FPP) system
FPP method has become very popular since it was introduced by
William Thomson (Lord Kelvin), who invented the Kelvin bridge in
1861 to measure very small resistances.
The DUT resistance RDUT canbe derived directly by dividing
the voltmeter indication Vm by
single measurement.
-
point probe system
four-point probe system
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Modified four-point probe method
The t ical current-volta e I-V measurements between
Sketch of the modified FPP system (19)* Micrograph of the modified FPP
system(19)*
each and every pair of pads
Repeated measurements at each applied voltage with the
po ar es o e e ec ro es n e g ven pa r sw c e or a
probing paths Derivation of the exact resistance of the nanowire from the
measured results
19 Gu W et.al., 2006 A l Ph s Lett 89:253102 1-3
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
* Reprinted with permission. Copyright 2006, American Institute of Physics
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1. The recent researches
2. Four-point probe method
3. Four-point AFM probe methodCombination with the conventional four-point probe method
and the atomic force microscope thereby providing a capability
4. Microwave AFM method
o c arac er ze e oca res s v y o me a c nanow res
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Four-point AFM probe method
One of the most important issues,
consequence that nanocircuits and nanodevices do not, usually, function
as ex ected.
A four-point AFM probe technique(20), (21)
e pro e no on y re a ns e a y o sur ace pro e mag ng u s
also capable of characterizing local conductivity simultaneously.
hundreds nanometers and work at AFM contact mode.
The average force applied to the surface is smaller than 10 pN, which
prov es a non es ruc ve measuremen an s ensures goo
electrical conduction between probe and sample.
sample can be eliminated.
20 Ju Y et.al., 2005 Rev Sci Instrum 76:086101 1-3
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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(21) Ju BF et.al., (2007) J Phys D: Appl Phys 40:7467-7470
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Fabrication of four-point AFM probe
-
Dimension: 100m 30m.
Tip height: 7.0mSpring constant: 6pN/nm
(The probe is coated with 30nm
gold film)SEM ima es of the four- oint AFM
probe, (A) before and (B) after FIB
fabrication(21)
The electrodes were introduced by fabricating three slits at the tip
of the cantilever utilizing a focused ion beam system (FIB). The
,
approximately 300nm and those of the outer pairs (electrodes 1, 2
& 3, 4) is approximately 1.0m.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
F b i i f f i AFM b
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Fabrication of four-point AFM probe
The gold film was etched to form
paths.
The device allows simultaneous
current transmission and
detection of electrical potential
The well-defined circuitry on the
probe surface and substrate for the
ur ose of a lied current and
.
electrical potential drop
measurements(21)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
A i l d it AFM i
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A nanowire sample and its AFM image
A 99.999% aluminum wire with
a width of 400 nm and a
thickness of 200 nm waspatterned by a typical procedure
.
The wire was on a TiN 200 nm/SiO2 (200 nm) / Si (525 m)substrate.
Optical image showing the 99.999% Alwire that was prepatterned by using
.
inset is an SEM image of the wire that
gives more details of its profile and
dimensions scale bar 500 nm(21)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
A i l d it AFM i
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A nanowire sample and its AFM image
four-point AFM probe
The scanning area: 4.04.0 m
The scanning rate: 0.25 Hz
reproducible, but a few fuzzy
scratches were observed.
Splitting the tip of the probe into four
wobble induced by the forceinhomo eneit .
AFM topography images of the Al wire,
which were obtained by the four-pointAFM probe(21)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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M i th d ti it f i
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Measuring the conductivity of nanowire
Durin scannin , the two outer
electrodes act as the current source
and drain, while the inner ones
using a digital voltmeter.
-
The slope of S-A is corresponding
to the conductivity of TiN.
(ii) A-B: Moving of the electrodes
Typical current-voltage relationship of Al
wire obtained by the four-point AFM
probe technique(21)
The slope of A-B indicates theaverage of conductivities of TiN
substrate and of the Al nanowire.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
Measuring the conductivity of nanowire
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Measuring the conductivity of nanowire
(iii) B-C: The two inner electrodes
located on the Al nanowire and the
surface of TiN The slope of B-C is corresponding
to the conductivity of the Al
nanowire.
(iv) C-D: The electrodes going down
from the nanowire in sequence, a
situation similar to that of case (ii).
-
Typical current-voltage relationship of Al
wire obtained by the four-point AFMprobe technique(21)
TiN substrate again, similar to case (i).
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Measuring the conductivity of nanowire
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Measuring the conductivity of nanowire
simultaneously the dimensions of
the wire at the nano-level, this
ensures the precision of theconductivity calculation.
comparable with each other.
The calculated conductivities of the Al
This work provides a basis for fast
in situcharacterization and fault-w res w t t e same t c ness ut
different widths of 400 nm, 1.2 m, 5.0m, 12.0 m and 25.0 m. The current-
finding of submicron interconnects
in nanocircuits and nanodevices.
vo age measuremen or eac w re was
carried out ten times, the error bars
correspond to the mean SD(21)
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1. The recent researches
2. Four-point probe method
3. Four-point AFM probe method
4. Microwave AFM method
Measurement of the topography and distribution ofelectrical properties of nanomaterials simultaneously
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
Microwave AFM Method
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Microwave AFM Method
An evaluation apparatus which has the spatial resolution ofnanometer scale
Scannin robe microsco e SPM
Scanning tunneling microscope (STM)
Near-field scanning optical microscope (NSOM)
topography of materials but also the thickness of oxidized membrane,
the rofile of the two-dimensional do ant (22) the distribution of the
electrical potential and the magnetic field on the material surface
(23)
,the distribution of the hardness and stiffness on the material surface (24)
an so on n nanome er or er.
(22) Kopanski JJ et.al., (1996) J Vac Sci Technol B 14:242-247
(23) Martin Y et.al., (1988) Appl Phys Lett 52:1103-1105
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
(24) Petzold M et.al.,(1995) Thin Sol Films 264:153-158
Microwave AFM Method
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Microwave AFM Method
Microwave microscope
defects in the microscopic region
Duewer et al. (25) succeeded in measurin resistivit of Cr, Zr and Mn b
using the characteristic of microwaves that the resonant frequency changesdepending on the capacitance between a probe tip and a material surface.
- (26)
depletion regions in solar cell p-n junctions in real time with the evanescent
microwave probe.
.
circuit packages by applying the properties of microwaves signals that
change depending on the electrical properties of materials.
Necessity of keeping the standoff distance between a microwaverobe and sam le constant
(25) Duewer F et.al., (1999) Appl Phys Lett 74:2696-2698
(26) Tabib-Azar M, Akiwande D, (2000) Rev Sci Instrum 71:1460-1465
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
(27) Ju Y, et.al., (2001) IEEE Trans Instrum Meas 50:1019-1023
Microwave AFM Method
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Microwave AFM Method
New SPM system for measurement of electrical properties,con uc v y, perm v y an permea y, n oca area
High spatial resolution Standoff distance control in
Microwave technique
Schematic diagram of the M-AFM probe
used for measuring the electrical
properties of materials
Microscope (M-AFM)(28)-(31)
(28) Ju Y et.al., (2005) Proc interPACK 2005 (CD-ROM):73140
(29) Ju Y et.al., (2007) Proc interPACK 2007 (CD-ROM):33613
(30) Ju Y et.al., (2008) Microsyst Technol 14:1021-1025
-
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
. .,
Fabricating the Tip of M-AFM Probe
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Fabricating the Tip of M-AFM Probe
M-AFM probe of made ofGaAs substrate
The attenuation of
(a) (b)A side-etching property by
wet etching
A sphalerite structure
being 45 to the direction can form a tip with a
(c) (d)
SEM photograph of the tips fabricated by etching
higher aspect ratio comparing
with the case of one side of
etching mask; (b) by 14 m etching mask; (c) by15 m etching mask; (d) enlarged part of the tip
(28)
parallel to direction.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Fabrication of M-AFM Probe
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Fabrication of M-AFM Probe
plane direction (1 0 0)
undoped (semi-insulating)
Cantilever
mens ons
Holder
2,750720340 m
impedance of 50
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Fabrication of M-AFM Probe
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Fabrication of M AFM Probe
.
the tip fabrication
.
wet etching
.
the waveguide on the top surface
.
surface
. -
process
.
the cantilever fabrication
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COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
Fabrication of M-AFM Probe
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Fabrication of M AFM Probe
.
probe by wet etching
.
on back side for the holder
fabrication
i. Forming the holder of the probe
b wet etchin
j. Coating metal film on the
bottom surface to form the
waveguide
k. Formin the o en structure at
the tip of the probe by FIB
fabrication
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Fabrication of M-AFM Probe
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Fabrication of M AFM Probe
(a) The M-AFM probes on a quarter of
(b) A cantilever of the M-AFM probe
(c) A micro slit introduced across the
with the width no more than 100 nm
(d) High-magnification image of the tipa b
The tip height:
8 mDimensions of the cantilevers:
25431.611.1 mDimensions of the bodies of the robes:
2743721338 mThe value of the characteristic impedance:
c
SEM photograph of the fabricated M-AFM
probes
.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Measuring Topography by M-AFM Probe
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Measuring Topography by M AFM Probe
The AFM topography of gratingsample having 2000 line/mm
Scan area: 33 m2
-
(b) M-AFM probe C(c) M-AFM probe E
(a) (b)
The commercial Si probe still
topography due to the higher
aspect ratio of the tip.
- pro e as a s m ar
capability for sensing surface
c
Surface topography of the grating
sam le measured b different robes(30)
of commercial AFM probes.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Measuring Topography by M-AFM Probe
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Measuring Topography by M AFM Probe
The AFM topography of
grating sample having 17.9
nm step e g t
(a ) The step height of M-
AFM probe:
18.60 nm
(a) (b)
(b) The step height of the
commercial Si probe:
Surface topography and scanning profile of the
.
M-AFM probe C; (b) commercial Si probe(30)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Connection of the fabricated probe and a microwave source
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p
was used to connect the fabricated
probe with a microwave source
The outer and inner conductors ofthe coaxial line are connected to the
bottom and to surfaces of the M-Coaxial
CableWire
M-AFM Probe
AFM probe, respectively
Connect to AFMCoaxial cable Wire
microwave source
Fabricated probe
ro e o er
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Measurement Using M-AFM
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g
The connection of the AFM with the microwave instrument
Microwaveima in
Microwave Generator
Isolator Multiplier
Computer Microwave compact instrument
Detector Circulator
Rock-in Amp.Topography
imagingPhotodetector Stage
controller
ProbeSpecimen
AFM
The schematic diagram of the M-AFM system
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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Microwave Image Obtained by M-AFM
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g y
M-AFM images: (a) AFM topography image of the sample (Au film coating on glass
wafer substrate) obtained by the M-AFM probe, (b) microwave image by converting
a
the measured microwave signals into the voltage without calibration(32)
M-AFM working mode: noncontact
Scanning speed: 5m/sec
Scanning area: 10m10m
(b) Measured outputting voltageAu: 265 mV, Glass: 285 mV
and glass wafer substrate)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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(32) Zhang L et.al.,(2010) Rev Sci Instrum 81:123708(1-4)
Measurement of Electrical Properties by M-AFM
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p y
Since the reflection from bottom surface can be neglected, the measuredreflection coefficient of the microwave signal can be expressed by
considering the reflection only from the top surface as(33)
0
0
j
0
0
represents the reflection coefficient, and , , , and areintrinsic im edance, conductivit , ermeabilit , and ermittivit of
materials, respectively, and 0, 0, 0, and 0 are those of free
space. Symbol denotes the angular frequency, and .1j
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
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, . , . .
Measurement of Electrical Properties by M-AFM
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For non magnetic materials, considering =0, and using the aboveequations, the reflection coefficient, , can finally be written as(34)
001 jjYX
coefficient.Y: the ima e art of the
00
1
j reflection coefficient.
By solving the simultaneous equations of the real and imaginary parts
of the e uation and eliminatin e, the conductivit of materials can be
expressed as
2214 YXY
2
YX
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
. ., -
Measurement of Electrical Properties by M-AFM
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On the other hand, the amplitude, |m|, and the phase, m, of themeasured reflection coefficient, m, can obtained by microwavemeasurement using following equation
mj
mm e
, m but also the standoff distance, reflection generated at the aperture part
of the probe, the connection parts between the probe and coaxial line,
and so on. Therefore, to examine a correct value of, we must find the
theoretical reflection coefficient tby calibrating the measured m.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
Measurement of Electrical Properties by M-AFM
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B usin and
mcan expressed as(33)
Signal flow graph for the reflection
t
tm
S
SS
a
b
2
22
2
12
11
1
1
1
1 1 , 11, 12
and S22 are errors of the measurement system including losses andphase delays caused by the effects of the connectors, cables and
the M-AFM probe.
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
Measurement of Electrical Properties by M-AFM
7/29/2019 Basics of Electrical Conductivity
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B solvin the e uation of revious a e the theoreticalreflection coefficient can expressed as
)( 1122
212
11
SSS m
m
t
21323221
22
mmttmmtt
S 2132132213 mmtttmmttt
222122212 )1)(1)(( ttmm SS
21
12
tt
2S
122
1111 t
mS
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
44
Measurement of Electrical Properties by M-AFM
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The measured amplitude and phase of the reflection coefficient verses the, , ,
(BS) and stainless steel (SST) surfaces, by a M-AFM probe(35)
(a) (b)Results of microwave measurement: a the relationshi between the am litude of
reflection coefficient and the electrical conductivity; (b) the relationship between the
phase of reflection coefficient and the electrical conductivity
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
(35) Fujimoto A et.al., (2011) Microsyst Technol 17:(in press)
Measurement of Electrical Properties by M-AFM
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Each mwas obtained by
carrying out the calibration as
escr e a ove us ng e
other three ones as the
.
microwave measurement can
discriminate the conductivity of
The relationship between the conductivity, m,obtained by the microwave measurement
the metallic micro and nano
materials quantitatively.
an e con uc v y, t, measure y a g -
frequency conductometry(35)
Basic 10 Micro-Nano Materials Characterization and Inspection Prof. Yang Ju- Evaluation of Electrical Properties-
COE for Education and Research of Micro-Nano Mechatronics, Nagoya University
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