1. Professor Ronald L. Carter ronc@uta.edu http://www.uta.edu/ronc/
EE5342 – Semiconductor Device Modeling and Characterization Lecture 29 - Spring 2004
Professor Ronald L. Carter
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2. MOSFET Device Structre Fig. 4-1, M&A*
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3. MOSFET equivalent circuit elements
Fig 10.51*
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4. n-channel enh. circuit modelG RG
Cgd
RDS
Cgs S RD D
Cbd RB
Cbs
Idrain
Cgb
DSS
DSD RB B
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5. MOS small-signal equivalent circuit
Fig 10.52*
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6. MOSFET circuit parameters
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7. MOSFET circuit parameters (cont)
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8. Substrate bias effect on VT (body-effect)
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9. Body effect data
Fig 9.9**
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10. Fully biased n- channel VT calc
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11. Values for fms with silicon gate
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12. Q’d,max and xd,max for biased MOS capacitor
Fig 8.11**
|Q’d,max|/q (cm-2)
xd,max (microns)
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13. I-V relation for n-MOS ohmic ID non-physical ID,sat saturated VDS,sat
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14. MOS channel- length modulation
Fig 11.5*
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15. Analysis of channel length modulation
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16. Channel length mod- ulated drain char
Fig 11.6*
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17. Associating the output conductanceID
ID,sat
VDS,sat
VDS
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18. SPICE mosfet Model Instance CARM*, Ch. 4, p. 290
L = Ch. L. [m]
W = Ch. W. [m]
AD = Drain A [m2]
AS = Source A[m2]
NRD, NRS = D and
S diff in squares
M = device multiplier
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19. SPICE mosfet model levels
Level 1 is the Schichman-Hodges model
Level 2 is a geometry-based, analytical model
Level 3 is a semi-empirical, short-channel model
Level 4 is the BSIM1 model
Level 5 is the BSIM2 model, etc.
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20. SPICE Parameters Level 1 - 3 (Static)
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21. SPICE Parameters Level 1 - 3 (Static)
* 0 = aluminum gate, 1 = silicon gate opposite substrate type, -1 = silicon gate same as substrate.
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22. SPICE Parameters Level 1 - 3 (Q & N)
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23. References
CARM = Circuit Analysis Reference Manual, MicroSim Corporation, Irvine, CA, 1995.
M&A = Semiconductor Device Modeling with SPICE, 2nd ed., by Paolo Antognetti and Giuseppe Massobrio, McGraw-Hill, New York, 1993.
M&K = Device Electronics for Integrated Circuits, 2nd ed., by Richard S. Muller and Theodore I. Kamins, John Wiley and Sons, New York, 1986.
Semiconductor Physics and Devices, by Donald A. Neamen, Irwin, Chicago, 1997
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