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Characterization of FD-SOI MOSFETs Based on EKV
model
Daniel Tomaszewski1, Denis Flandre2, Piotr
Grabiec1, Andrzej Kociubinski1, Christian
Renaux2, Krzysztof Kucharski1 1 Institute of
Electron Technology, Warszawa, Poland 2
Université Catholique de Louvain,
Louvain-la-Neuve, Belgium presented by Daniel
Tomaszewski MOS-AK Workshop, Grenoble, 2005
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OUTLINE

• MOTIVATION
• MOSTXX APPLICATION
• EKV MODEL IMPLEMENTATION
• EXTRACTION OF THE PARAMETERS
• SUMMARY, FUTURE

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MOTIVATION
The FD-SOI becomes an attractive choice for small
research groups and SMEs, where research
projects related to ASICs /MEMS integration are
carried out. A MOSTXX application for MOSFET
parameter extraction has been developed in the
ITE as a cost effective tool for characterization
of the CMOS ICs. Recently the EKV model, has been
implemented. The paper reports results of EKV
model parameter extraction for the FD-SOI
MOSFETs. The analysis has been done using the
MOSTXX software.
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MOSTXX application

• Integration with MS Excel
• Local extraction
• Threshold voltage
• Mobility
• Global extraction
• MOSFETs parameters
• Diodes parameters (I-V, C-V)
• Extraction of dimensions variations using sets of
  devices

Area component
Edge component
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EKV MODEL IMPLEMENTATION
The EKV model accounts for weak and strong
inversion ranges and is based on interpolation of
F(v)
The Oguey, Cserveny approximation
The approximation in the EKV enhanced in order to
calculate F(v)
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TECHNOLOGY
0.752 µm FD-SOI CMOS process on SmartCut
UNIBOND wafers. Semi-recessed LOCOS used to
isolate the devices.
n-poly-Si gate material Boron implantation of
the n- and p-channel MOSFETs Basic parameters of
the process Buried oxide thickness TBOX
400 nm Final thickness of the silicon film TSi
80 nm Gate oxide thickness TOX 31 nm Junction
depth XJ TSi(assumed)
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DEVICES
I(VGS) data of intrinsic (I-type) n- and
p-channel MOSFETs
I(VGS) data of highly doped (P12-type) n- and
p-channel MOSFETs
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DEVICES
I(VDS) data of P2- and P12-type n-channel
MOSFETs cumulative boron implantation gives so
high boron concentration in the Si film, that
kink-effect appears
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EXTRACTION OF PARAMETERS
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SUMMARY
The EKV model implemented in optimization tool
may be useful for characterization of FD-SOI MOS
transistors. The results of extraction of FD SOI
MOSFETs parameters Square-root VT(VB)
dependence should be revised P-channel MOSFETs
devices will be characterized

• GAM, PHI parameters estimated manually because
  of too small number of back gate bias voltages.
• VTO, KP, UCRIT, LAMBDA related to boron
  concentration
• NUO is below 1, except of I-type device

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Thanks a lot for your attention
Acknowledgement The authors would like to
express thanks to Dr Wladyslaw Grabinski from
Geneva Modeling Center, Freescale for
encouragement towards this work and helpful
discussions during its preparation.
http//www.ite.waw.pl dtomasz_at_ite.waw.pl