BSIM4 Version 5

BSIM4.5.0 has the following new features:

• A mobility model which accounts for Coulomb scattering effect as well as the channel length dependence of mobility due to heavy halo-doping
• A scalable substrate resistance model (rbodyMod = 2) that is scalable with channel length, channel width, and number of fingers
• Gate resistance parameters XGW, NGCON that can now be specified as instance parameters (XGL is still a model parameter)
• Additional temperature dependence of model parameters VOFF and VFBSDOFF
• Enhanced tempMod = 2, where Vth(DITS) and gate tunneling models are functions of nominal temperature and the temperature dependence of zero-bias flat-band voltage is added
• A new instance parameter DELVTO that may be used to represent threshold voltage variation
• A new well-proximity effect model developed by CMC companies
• Igc Vbs dependence improvement with the full BSIM4 Vth model implemented

Mobility Model

Mobility Coulomb Scattering Model and Leff dependence

(-239)

mobMod=0

(-240)

mobMod=1

(-241)

mobMod=2

where the constant C0 = 2 for NMOS and 2.5 for PMOS.

(-242)

Scalable Substrate Resistance Model

(-243)

Temperature Dependence for VOFF, VFBSDOFF

(-244)

(-245)

New Temperature Mode (TempMod = 2)

Share the same temperature equations as for TempMod=1 with the following modifications:

From

(-246)

To

(-247)

Vfbzb(T)

(-248)

Igate(T)

T is replaced by TNOM

DELVTO: An Instance Parameter

if vth0 is given:

(-249)

if vth0 is not given,

(-250)

(-251)

Well-Proximity Effect Modeling

Instance parameters: SCA, SCB, SCC, SC

Model parameters: WEB, WEC, KVTH0WE, K2WE, KU0WE, SCREF, WPEMOD

Model equations:

(-252)

(-253)

(-254)

Gate Current Vbs Dependence

(-255)

For IGCMOD=1

(-256)

For IGCMOD=2

(-257)

Implementing full BSIM4 Vth model into Igc enables the accurate prediction of Igc Vbs dependence.

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