Semicond - 1www.semilab.com
SEMILAB’s PRODUCTS for the
SEMICONDUCTOR INDUSTRY
SEMILAB Semiconductor Physics Laboratory, Inc.Prielle Kornelia u. 2, H-1117 Budapest, Hungary
Tel:36-1-382-4530 Fax: 36-1-382-4532 E-mail: [email protected] site: www.semilab.com
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Wafer Mapping Toolsfor high speed, high resolution
whole wafer mapping of defects and/or contaminants
Deep Level Spectrometerfor identification of electrically active point
defects
Bulk Microdefect Analyzerfor imaging of extended defects (from
20nm to several micron)
Resistivity Testerfor non-contact determination of
bulk resistivity
in blocks and feedstock material in wafers
p/n Testerfor non-contact determination of
conductivity type (p or n) of the material
Semiconductor Characterization Systems
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Wafer Mapping Tools
WT-2000 Wafer Testermonitoring defects and contamination both in the bulk and in the surface region of silicon wafers
Applied measurement techniques:-PCD for bulk Si
Charge-PCD for bare wafersEpiTest for epi wafers
SPV for bulk SiV-Q for oxide characterizationEddy current for resistivity mapping
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In-line Monitoring Tool
WT-3000 model forin-line
contamination monitoring
• SPC product wafer
• Iron contamination mapping - 10x faster than SPV
• Full wafer monitoring due to high mapping speed
• Integrated minienvironment including FOUP loadport, robot and pre-aligner
Fe
Fe
Fe
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WT-2000 -PCD Tool-PCD (microwave photoconductive decay) technique for mapping crystal growth and process induced defects and heavy metal contamination in bulk silicon wafers
APPLICATIONSCRYSTAL GROWTH DEFECTS
PROCESS INDUCED DEFECTS/Fe MAPPING
Laser
Microwave
wafer
I = I0 e-t/Slip lines Oxygen striations OSF ring
Contaminatedvacuum chuck
Fe detectionBoat contamination
Fe
Fe
Fe
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WT-2000 SPV Tool
Surface Photovoltage (SPV) technique for mapping heavy metal contamination and crystaldefects in the bulk silicon wafer
IRON CONCENTRATIONMAPPING
Fe
12
34
1/
/VSPV
L
VSPV
= C(L+1/)
Fe AND O2 MONITORING BYCOMBINED -PCD AND SPVTECHNIQUES
Life
time,
s
0.01
0.1
1
Injection level, 1/cm31.E+11 1.E+13 1.E+15 1.E+17
SPV -PCD
Fe-B pairO2 prec.NFe = C ( )1
Lafter2
1Lbefore
2-
SPV -PCD
oxygen iron
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WT-2000 Charge-PCD
Laser
Microwave
waferCharging
Charging1
1meas
1bulk
= 1diff surf++
Semilab’s patented new surface passivation method applying controlled charge deposition on to the wafer surface during lifetime mapping provides a highly efficient, reproducible and homogeneous surface recombination elimination on bare wafers.
without charging with charging
Surface /interface characterization
Interface recombination velocity map of an oxidized wafer calculated from the lifetime map measured with and without charging on the same wafer
average=15.7 s average=268 s
Lifetime map measured
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WT-2000 V-Q ToolFast, non-contact measurement technique, that replace the traditional contact C-Vmeasurements for qualifying the oxide/interface in silicon wafer
Charge
.. ............ . .
Light/Kelvin probe
Charge, nC/cm2
SP
V, V
0
0.5
1
-0.5
Theoritical
Dark-corrected bright
0100 100
Tox Electrical oxide thicknessVfb Flatband voltageDit Interface state densityQm Mobile chargeVox Oxide voltageQeff Effective chargeEtunnel Tunelleing electric fieldVs Surface potentialVsurf Surface voltageVtunnel Tunnel voltage
Non-contact V-Q combinesthree non-contact methods:
• Corona discharge• Kelvin Probe• Illumination
Electrical oxide thickness
26 Ao
24 Ao
Etunnel
-11V
-6.8V
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WT-2000 Epitest
Improved -PCD (microwave photoconductive decay) technique for the characterizationof recombination processes in epi structures.
Light excitation
Oxide or passivation.
MicrowaveGreen laser
532nm
Epi layer
p+ or n+ substrate
Ssurface
Sinterface
epi
substrate
Lifetime map Fe concentration map
13.8s 14.8s 5 E91/cm3
3 E101/cm3
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WT-2000 Resistivity Mapper
Controlelectronics
High frequency coil
Headheightcontrol
Non-contact whole wafer resistivity mapping based on the eddy current technique for thedetermination of bulk resistivity distribution in silicon wafers
Resistivity map
Single crystal8” CZ wafer
Multi-crystallinePV material
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WT-2000 MCTTemperature Dependent Lifetime
Temperature dependent carrier lifetime measurements
50 100 150 200 2500.01
0.1
1
sample 1 sample 2
Temperature [K]
Life
time
[µs]
50 100 150 200 250
0.1
0.2
0.3
0.4
0.5
Temperature [K]
Life
time
[µs]
sample #2 sample #4
HgCdTe InSb
Monitoring minority carrier lifetime as a function of temperature in narrow band gapsemiconductors (InSb, HgCdTe, etc.)
Two measurement strategies:• whole wafer mapping at a preselected stabilized temperature
between 85K and 300K• single point lifetime plot as a function of temperature
between 85K and 300K
100 150 200 250 3000.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
Life
time
[µs]
Temperature [K]
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SIRM-300Bulk Microdefect Analyzer
Non-contact, non-destructive method based on reflection mode confocal microscopyfor detection and analysis of bulk microdefects
Dislocations Stacking fault
laser
beamsplitter
Z scanning
X-Y scanning
detector
wafer
Denuded zone determination
depth
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Light Scattering TomographMicro- and Grown-in Defects Analyzer
y=0.2508x+18.896
R2 = 0.9969
0
10
20
30
40
50
60
0 50 100 150 200
Cumulative BMD number
Dep
th [µ
m] DNZ depth: 18.9µm
Near surface analysis surface
5m
Denuded zone determination
The BMDs scatter the incident light which is recorded by a CCD camera near to the cleaved edge of the sample
•High Sensitivity - Detectable Particle Size down to 10 nm•High Depth Resolution - 0.5 μm•High Measurement Speed, 50 sec/2mm x 400 μm•Fully automatic operation including half wafer handling •Stabilized Laser Wavelength•Variable Laser Power
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DLS-83DDeep Level Spectrometer
Detection and identification of trace level of impurities in concentrations down to 109 atoms/cm3
CRYOSTATSIN DIFFERENT TEMPERATURE RANGES
• Closed Cycle He-cryostat from 20K to 300K• LN2 cryostats from 77K to 450K: simple bath type LN2 cryostat automatic LN2 cryostat with controlled LN2 flow
SAMPLE HOLDERwith motor driven positioning
in n-type FZ silicon
Cs-Sii-Cs Ps-Ci(1)Vac-Vac
Ps-Ci(2)
P-Vac
Vac-O
Vac-Vac
Vac-?
?
Cs-Oi
C-O-V2
or
Ci
in p-type FZ siliconRadiation defects
Influence of annealingon Fe-B pairs
Fe-B pair
Fe-interstitial
Molybdenum
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Epimet delivers the industry’s first realtime, non-contact method to measure epi layer resistivity profiles in production. Fast feedback and the availability of resistivity profile plots and wafer maps aid in troubleshooting for still higher control over epi processes.
EpimetFast, Repeatable Measurements Without Wafer Damage
Resitivity profile measured by Epimet
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Surface Charge AnalyzerThe Surface Charge Analyzer allows real-time monitoring of contamination and damage in the critical semiconductor manufacturing processes, such as thermal oxidation, CVD film deposition, metallization, and etch processes.
Wafer maps indicating backstreaming
SourceAvg Qox: 8E10q/cm2
LoadAvg Qox: 2E11q/cm2
p-typesilicon
SiO2
Wd
Photons (Light)
-+
Induced charge, Qind
Dep
letio
n w
idth
, Wd(
m)
Onset on InversionInversion
Midgap
AccumulationP-type Oxidized Wafer
Typical SCA Curve
Nsc
Qox
Dit
