Model Version Update

Version 4.30

1. Introduced a stress effect model for process induced stress effect;
2. Introduced a temperature model format to predict temperature effects on saturation velocity, mobility, and S/D resistances;
3. Introduced a unified current saturation model that includes all mechanisms of current saturation- velocity saturation, velocity overshoot and source end velocity limit and quasi-ballistic transport;
4. Enhanced holistic thermal noise model;
5. Enhanced forward body bias model;
6. Extended gate direct tunneling model to multiple-layer gate stacks.
7. Fixed minor bugs.

Version 4.40

1. Introduced a trap-assisted tunneling and recombination current model, which is applicable to gate-edge side-wall, STI-edge side-wall and bottom junction;
2. Introduced a flatband voltage offset parameter (vfbsdoff) to improve gate overlap tunneling current;
3. Introduced an offset parameter (lintnoi) to length reduction parameter (lint) to improve the accuracy of the flicker noise model;
4. Fixed minor bugs.

Version 4.50

1. Introduced a mobility model which accounts for Coulomb scattering and the channel length dependence of mobility due to heavy halo-doping;
2. Introduced a substrate resistance model (rbodymod = 2), which is scalable with channel length, channel width and number of fingers;
3. Specified gate resistance parameters xgw and ngcon as instance parameters;
4. Improved temperature dependence for model parameters voff and vfbsdoff;
5. Enhanced temperature model (tempmod = 2), where Vth (DITS) and gate tunneling models are functions of nominal temperature and the temperature dependence of flat-band voltage is added;
6. Introduced a new instance parameter delvto to represent threshold voltage variation;
7. Enhanced well-proximity effect model, enable some device parameters to vary with distance from the edge of well-implantation mask due to ion-scattering;
8. Implemented a full BSIM4 Vth model into the Igc equation which enables accurate prediction of the Vbs dependence of Igc.
9. Fixed minor bugs.

Version 4.60

1. Introduced separated model parameters for the GIDL and GISL leakage current modules.
2. Introduced separated parameters for the source and drain side junction diode current due to the trap-assisted tunneling current in space-charge region.
3. Introduced separated parameters for the gate tunneling current in the S/D overlap diffusion regions (Igs/Igd).
4. Modified the coulomb scattering term in mobility model to avoid the possibility of non-monoticity in drain current trend with respect to gate voltage.
5. Improved the accuracy for rgatemod = 2 by accounting correctly the contribution from Rgate to overall noise.
6. Set the default value of the parameter vfb to -1.0V.

Version 4.61

1. Introduced new material model (by setting mtrlmod=1) for predictive modeling of non-SiO2 insulator, non-poly Silicon gate and non-silicon channel. Add new parameters including new material model selector (mtrlmod), non-poly silicon gate parameters (phig and epsrgate), non-SiO2 gate dielectric (eot and vddeot), and non-silicon channel parameters (easub, epsrsub, ni0sub, bg0sub, tbgasub, tbgbsub, ados, and bdos).
2. Improved mobility model (mobmod = 0 and 1) through predictive modeling of vertical electric field. The improved mobility model is selected through mtrlmod = 1 for backward compatibility.
3. Improved GIDL/GISL models through an improved definition of flatband voltages at S/D ends. The improved GISL/GIDL model is selected through mtrlmod = 1 for backward compatibility.
4. Modified poly-depletion model to account for new gate and gate-insulator materials.
5. Introduced a new VgsteffCV definition into C-V model (by setting cvchargemod = 1) to improve sub-threshold fitting. Add six new parameters including cvchargemod, minvcv, lminvcv, wminvcv, pminvcv and voffcvl.
6. Fixed an error in the derivative calculation of dVdseffCV_dVb for capmod = 1 and 2.
7. Removed warning messages for the limits of noff and voffcv.

Version 4.62

1. Included the width dependence in trap assisted tunneling (TAT) model. Introduce a new model parameter jtweff and set it to zero to maintain the backward compatibility.
2. Introduced mobility model (mobmod =3) to enhance the modeling of Coulomb scattering in the high-k/metal gate transistors.
3. Fixed minor bugs in:
   • Output conductance model: vascbe;
   • Thermal noise model (tnoimod=0);
   • Negative thermal noise (tnoimod=1);
   • Source/drain bulk junction capacitance;
   • Derivative issue in capacitance model (capmod=0);
   • Toxp calculation (mtrlmod=1);
   • Source/drain resistance;
   • Drain/body breakdown voltage.

Version 4.63

Fixed minor bug in litl calculation.

Version 4.64

1. Fixed bug in thermal noise model when tnoimod=1.
2. Removed duplicate counting of temperature coefficient when mobmod=3.
3. Updated Esat after EsatL calculation.

Version 4.65

1. Set Pseff and Pdeff to zero when they are negative and give a warning message.
2. Turn off source side diode by setting sourceSaturationCurrent=0.0 when Aseff and Pseff are zero. Turn off drain side diode by setting DrainSaturationCurrent=0.0 when Adeff and Pdeff are zero.

Version 4.70

1. Improved GIDL/GISL model from BIMSOI.
   • Add new model with flag gidlmod=1.
   • New binnable parameters rgidl (lrgidl, wrgidl, prgidl)/rgisl, kgidl/kgisl, and fgidl/fgisl have been introduced.
   • The previous GIDL/GISL model is in gidlmod=0.
   • Impacts igidl and igisl.
2. Improved DIBL/Rout model from BIMSOI.
   • Existing DIBL/Rout model in BSIM is proposed to enhance with additional term DVTP5 (with parameters DVTP2, DVTP3, DVTP4, DVTP5), to better capture Vds effect in long channel device.
   • Impacts Vth.
3. Improved sub-threshold temperature dependence.
   • Improve formulations to capture temperature dependence of Leakage Current with new parameters tnfactor, teta0, and tvoffcv.
4. Improved thermal noise model (tnoimod=2).
   • New noise models have been introduced as tnoimod=2. Added new parameters tnoic and rnoic. Correlated noise is considered.
5. Limiting of diode ideality factor (NJS,NJD).
6. New parameter mtrlCompatMod to ensure consistent results of mtrlMod=0 versus mtrlMod=1.
7. BugFix of Toxm.
   • Corrected Toxm setting in Initialize().
8. BugFix of igc.
   • Removed redundant toxe term appearing in the Igc formulation

Version 4.80

1. Three new mobility models mobmod=4, mobmod=5, and mobmod=6 have been introduced.
2. The derivative bugs in igcmod=2 have been fixed.
3. Some unused lines have been removed.
4. Parameter check on toxp has been adjusted.
5. The default value of fgidl has been changed to 1.0 for version 4.80.
6. Computational efficiency of rbsbx, rbsby, rbdby, rbpbx, rbpby, rbps0, and rbpd0 has been improved.

Version 4.81

• Abnormal Jitter noise temperature dependence with TNOIDMOD =1 is observed.
• Limitation on TNOIA, TNOIB, TNOIC and RNOIA being greater than zero is removed and limits have been added in the entire function.
• Warning message has been added for TNOIMOD=1.
• When DLCIG<0 or DLCIGD<0, it is clamped to zero and a warning message is generated.
• Model Equations related to Junction Diode IV have been updated.

Related Topics

BSIM4 Level-14 Model (bsim4)

JUNCAP Model

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