Metal Oxide Semiconductor Field-Effect Transistor (MOSFET) Model

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Modified by Phil Loughhead on Mar 4, 2014

Model Kind

Transistor

Model Sub-Kind

MOSFET

SPICE Prefix

SPICE Netlist Template Format

Parameters (definable at component level)

The following component-level parameters are definable for this model type and are listed on the Parameters tab of the Sim Model dialog. To access this dialog, simply double-click on the entry for the simulation model link in the Models region of the Component Properties dialog.

Length	channel length (in meters).
Width	channel width (in meters).
Drain Area	area of the Drain diffusion (in sq.meters).
Source Area	area of the Source diffusion (in sq.meters).
Drain Perimeter	perimeter of drain junction (in meters). (Default = 0).
Source Perimeter	perimeter of source junction (in meters). (Default = 0).
NRD	equivalent number of squares of the drain diffusion (Default = 1).
NRS	equivalent number of squares of the source diffusion (Default = 1).
Starting Condition	set to OFF to set terminal voltages to zero during operating point analysis. Can be useful as an aid in convergence.
Initial D-S Voltage	time-zero voltage across Drain-Source terminals (in Volts).
Initial G-S Voltage	time-zero voltage across Gate-Source terminals (in Volts).
Initial B-S Voltage	time-zero voltage across Bulk (substrate)-Source terminals (in Volts).
Temperature	temperature at which the device is to operate (in Degrees Celsius). If no value is specified, the default value assigned to TEMP on the SPICE Options page of the Analyses Setup dialog will be used (Default = 27).
M	multiplication factor. (Default = 1). This parameter is only available when using the EKV model.

Parameters (definable within model file)

The following is a list of parameters that can be stored in the associated model file, when using the Shichman-Hodges, MOS2, MOS3 or MOS6 models:

LEVEL	model index (Default = 1).
VTO	zero-bias threshold voltage V _TO (in Volts). (Default = 0).
KP	transconductance parameter (in A/V ² ). (Default = 2.0e-5).
GAMMA	bulk threshold parameter γ (in V ^1/2 ). (Default = 0).
PHI	surface potential φ (in Volts). (Default = 0.6).
LAMBDA	channel length modulation λ (in 1/V). This parameter is applicable to MOS1 and MOS2 model types only. (Default = 0).
RD	drain ohmic resistance (in Ohms). (Default = 0).
RS	source ohmic resistance (in Ohms). (Default = 0).
CBD	zero-bias B-D junction capacitance (in Farads). (Default = 0).
CBS	zero-bias B-S junction capacitance (in Farads). (Default = 0).
IS	bulk junction saturation current I _S (in Amps). (Default = 1.0e-14).
PB	bulk junction potential (in Volts). (Default = 0.8).
CGSO	Gate-Source overlap capacitance per meter channel width (in Farads per meter). (Default = 0).
CGDO	Gate-Drain overlap capacitance per meter channel width (in Farads per meter). (Default = 0).
CGBO	Gate-Bulk overlap capacitance per meter channel length (in Farads per meter). (Default = 0).
RSH	Drain and Source diffusion sheet resistance (in Ohms). (Default = 0).
CJ	zero-bias bulk junction bottom capacitance per square meter of junction area (in Farads/m ² ). (Default = 0).
MJ	bulk junction bottom grading coefficient (Default = 0.5).
CJSW	zero-bias bulk junction sidewall capacitance per meter of junction perimeter (in Farads/meter). (Default = 0).
MJSW	bulk junction sidewall grading coefficient (Default = 0.5 - LEVEL1; 0.33 - LEVEL2,3).
JS	bulk junction saturation current per square meter of junction area (in Amps/m ² ).
TOX	oxide thickness (in meters). (Default = 1.0e-7).
NSUB	substrate doping (in 1/cm ³ ). (Default = 0).
NSS	surface state density (in 1/cm ² ). (Default = 0).
NFS	fast surface state density (in 1/cm ² ). (Default = 0).
TPG	type of gate material: +1 (default) = opposite to substrate -1 = same as substrate 0 = Al gate
XJ	metallurgical junction depth (in meters). (Default = 0). This applies to Levels 2 (MOS2) and 3 (MOS3) only.
LD	lateral diffusion (in meters). (Default = 0).
UO	surface mobility (in cm ² /Vs). (Default = 600).
UCRIT	critical field for mobility degradation (in V/cm). This parameter is applicable to the MOS2 model only. (Default = 1.0e4).
UEXP	critical field exponent in mobility degradation. This parameter is applicable to the MOS2 model only. (Default = 0).
UTRA	transverse field coefficient (mobility). This parameter has been deleted with respect to the MOS2 model. (Default = 0).
VMAX	maximum drift velocity of carriers (in m/s). (Default = 0).
NEFF	total channel-charge (fixed and mobile) coefficient. This parameter is applicable to the MOS2 model only. (Default = 1).
KF	flicker noise coefficient (Default = 0).
AF	flicker noise exponent (Default = 1).
FC	coefficient for forward-bias depletion capacitance formula (Default = 0.5).
DELTA	width effect on threshold voltage. This parameter is applicable to MOS2 and MOS3 model types only. (Default = 0).
THETA	mobility modulation (in 1/V). This parameter is applicable to the MOS3 model only. (Default = 0).
ETA	static feedback. This parameter is applicable to the MOS3 model only. (Default = 0).
KAPPA	saturation field factor. This parameter is applicable to the MOS3 model only. (Default = 0.2).
TNOM	parameter measurement temperature (in °C) - If no value is specified, the default value assigned to TNOM on the SPICE Options page of the Analyses Setup dialog will be used (Default = 27).

The following is a list of parameters that can be stored in the associated model file, when using the BSIM or BSIM2 models:

LEVEL	model index (Default = 1).
VFB*	flat-band voltage (in Volts).
PHI*	surface inversion potential (in Volts).
K1*	body effect coefficient (in V ^1/2 ).
K2*	Drain/Source depletion charge-sharing coefficient.
ETA*	zero-bias drain-induced barrier-lowering coefficient.
MUZ	zero-bias mobility (in cm ² /Vs).
DL	shortening of channel (in μm).
DW	narrowing of channel (in μm).
U0*	zero-bias transverse-field mobility degradation coefficient (in V ^-1 ).
U1*	zer0-bias velocity saturation coefficient (in μm/V).
X2MZ*	sens. of mobility to substrate bias at V _ds =0 (in cm ² /V ² s).
X2E*	sens. of drain-induced barrier lowering effect to substrate bias (in V ^-1 ).
X3E*	sens. of drain-induced barrier lowering effect to drain bias at V _ds =V _dd (in V ^-1 ).
X2U0*	sens. of transverse field mobility degradation effect to substrate bias (in V ^-2 ).
X2U1*	sens. of velocity saturation effect to substrate bias (in μmV ^-2 ).
MUS	mobility at zero substrate bias and at V _ds =V _dd (in cm ² /V ² s).
X2MS*	sens. of mobility to substrate bias at V _ds =V _dd (in cm ² /V ² s).
X3MS*	sens. of mobility to drain bias at V _ds =V _dd (in cm ² /V ² s).
X3U1*	sens. of velocity saturation effect on drain bias at V _ds =V _dd (in μmV ^-2 ).
TOX	gate oxide thickness (in μm).
TEMP	temperature at which parameters were measured (in °C)
VDD	measurement bias range (in Volts).
CGDO	gate-drain overlap capacitance per meter channel width (in F/m).
CGSO	gate-source overlap capacitance per meter channel width (in F/m).
CGBO	gate-bulk overlap capacitance per meter channel length (in F/m).
XPART	gate-oxide capacitance-charge model flag.
N0*	zero-bias sub-threshold slope coefficient.
NB*	sens. of sub-threshold slope to substrate bias.
ND*	sens. of sub-threshold slope to drain bias.
RSH	drain and source diffusion sheet resistance (in Ohms).
JS	source drain junction current density (in A/m ² ).
PB	built-in potential of source drain junction (in Volts).
MJ	grading coefficient of source drain junction.
PBSW	built-in potential of source drain junction sidewall (in Volts).
MJSW	grading coefficient of source drain junction sidewall.
CJ	source drain junction capacitance per unit area (in F/m ² ).
CJSW	source drain junction sidewall capacitance per unit length (in F/m).
WDF	source drain junction default width (in meters).
DELL	source drain junction length reduction (in meters).

The following is a list of parameters that can be stored in the associated model file, when using the BSIM3 model:

LEVEL	model index (Default = 1).
MOBMOD	mobility model selector (Default = 1).
CAPMOD	flag for the short-channel capacitance model (Default = 2).
NQSMOD	flag for NQS model (Default = 0).
NOIMOD	flag for noise model (Default = 1).
VTH0	threshold voltage (at V _BS =0) for Large L (in Volts). (Default = 0.7 - NMOS; -0.7 - PMOS). (See BSIM3-Related notes).
K1	first-order body effect coefficient (in V ^1/2 ). (Default = 0.5). (See BSIM3-Related notes).
K2	second-order body effect coefficient (Default = 0). (See BSIM3-Related notes).
K3	narrow width coefficient (Default = 80).
K3B	body effect coefficient of K3 (in 1/V). (Default = 0).
W0	narrow width parameter (in meters) (Default = 2.5e-6).
NLX	lateral non-uniform doping parameter (in meters). (Default = 1.74e-7).
VBM	maximum applied body bias in Vth calculation (in Volts). (Default = -3.0).
DVT0	first coefficient of short-channel effect on Vth (Default = 2.2).
DVT1	second coefficient of short-channel effect on Vth (Default = 0.53).
DVT2	body-bias coefficient of short-channel effect on Vth (in 1/V). (Default = -0.032).
DVT0W	first coefficient of narrow width effect on Vth for small channel length (in 1/m). (Default = 0).
DVT1W	second coefficient of narrow width effect on Vth for small channel length (in 1/m). (Default = 5.3e6).
DVT2W	body-bias coefficient of narrow width effect for small channel length (in 1/V). (Default = -0.032).
U0	mobility at TEMP = TNOM (in cm ² /V/s). (Default = 670.0 - NMOSFET; 250.0 - PMOSFET).
UA	first-order mobility degradation coefficient (in m/V). (Default = 2.25e-9).
UB	second-order mobility degradation coefficient (in (m/V) ² ). (Default = 5.87e-19).
UC	body-effect of mobility degradation coefficient. For MOBMOD = 1 or 2, measured in m/V ² , Default = -4.65e-11 For MOBMOD = 3, measured in 1/V, Default = -0.046.
VSAT	saturation velocity at TEMP = TNOM (in m/sec). (Default = 8.0e4).
A0	bulk charge effect coefficient for channel length (Default = 1.0).
AGS	gate bias coefficient of Abulk (in 1/V). (Default = 0).
B0	bulk charge effect coefficient for channel width (in meters). (Default = 0).
B1	bulk charge effect width offset (in meters). (Default = 0).
KETA	body-bias coefficient of bulk charge effect (in 1/V). (Default = -0.047).
A1	first non-saturation effect parameter (in 1/V). (Default = 0).
A2	second non-saturation factor (Default = 1).
RDSW	parisitic resistance per unit width (in Ω-μm ^WR ). (Default = 0).
PRWB	body effect coefficient of RDSW (in V ^-1/2 ). (Default = 0).
PRWG	gate bias effect coefficient of RDSW (in 1/V). (Default = 0).
WR	width offset from Weff for RDS calculation (Default = 1).
WINT	width offset fitting parameter from I-V without bias (in meters). (Default = 0).
LINT	length offset fitting parameter from I-V without bias (in meters). (Default = 0).
DWG	coefficient of Weff's gate dependence (in m/V). (Default = 0).
DWB	coefficient of Weff's substrate body-bias dependence (in m/V ^1/2 ). (Default = 0).
VOFF	offset voltage in the subthreshold region at large W and L (in Volts). (Default = -0.08).
NFACTOR	subthreshold swing factor (Default = 1).
ETA0	DIBL coefficient in subthreshold region (Default = 0.08).
ETAB	body-bias coefficient for the subthreshold DIBL effect (in 1/V). (Default = -0.07).
DSUB	DIBL coefficient exponent in subthreshold region (Default = DROUT).
CIT	interface trap capacitance (in F/m ² ). (Default = 0).
CDSC	Drain/Source to channel coupling capacitance (in F/m ² ). (Default = 2.4e-4).
CDSCB	body-bias sensitivity of CDSC (in F/Vm ² ). (Default = 0).
CDSCD	Drain-bias sensitivity of CDSC (in F/Vm ² ). (Default = 0).
PCLM	channel length modulation parameter (Default = 1.3).
PDIBLC1	first output resistance DIBL effect correction parameter (Default = 0.39).
PDIBLC2	second output resistance DIBL effect correction parameter (Default = 0.0086).
PDIBLCB	body-effect coefficient of DIBL correction parameters (in 1/V). (Default = 0).
DROUT	L dependence coefficient of the DIBL correction parameter in Rout (Default = 0.56).
PSCBE1	first substrate current body-effect parameter (in V/m). (Default = 4.24e8).
PSCBE2	second substrate current body-effect parameter (in m/V). (Default = 1.0e-5).
PVAG	gate dependence of Early voltage (Default = 0).
DELTA	Effective Vds parameter (in Volts). (Default = 0.01).
NGATE	poly gate doping concentration (in cm ^-3 ). (Default = 0).
ALPHA0	the first parameter of impact ionization current (in m/V). (Default = 0).
BETA0	the second parameter of impact ionization current (in Volts). (Default = 30).
RSH	source drain sheet resistance (in Ω/square). (Default = 0).
JS	source drain junction saturation current per unit area (in A/m ² ). (Default = 1.0e-4).
XPART	charge partitioning rate flag (Default = 0).
CGSO	non LDD region source-gate overlap capacitance per channel length (in F/m). (See BSIM3-Related notes).
CGDO	non LDD region drain-gate overlap capacitance per channel length (in F/m). (See BSIM3-Related notes).
CGBO	gate bulk overlap capacitance per unit channel length (in F/m). (Default = 0).
CJ	bottom junction capacitance per unit area (in F/m ² ). (Default = 5e-4).
MJ	bottom junction capacitance grating coefficient (Default = 0.5).
MJSW	Source/Drain side junction capacitance grading coefficient (Default = 0.33).
CJSW	Source/Drain side junction capacitance per unit area (in F/m). (Default = 5e-10).
CJSWG	Source/Drain gate sidewall junction capacitance grading coefficient (in F/m). (Default = CJSW).
MJSWG	Source/Drain gate sidewall junction capacitance coefficient. (Default = MJSW).
PBSW	Source/Drain side junction built-in potential (in Volts). (Default = 1.0).
PB	bottom built-in potential (in Volts). (Default = 1.0).
PBSWG	Source/Drain gate sidewall junction built-in potential (in Volts). (Default = PBSW).
CKAPPA	coefficient for lightly doped region overlap capacitance (in F/m). (Default = 0.6).
CF	Fringing field capacitance (in F/m). (See BSIM3-Related notes).
CLC	constant term for the short channel model (in meters). (Default = 0.1e-6).
CLE	exponential term for the short channel model (Default = 0.6).
DLC	length offset fitting parameter from C-V (in meters). (Default = LINT).
DWC	width offset fitting parameter from C-V (in meters). (Default = WINT).
ELM	Elmore constant of the channel (Default = 5).
WL	coefficient of length dependence for width offset (in m ^WLN ). (Default = 0).
WLN	power of length dependence for width offset (Default = 1.0).
WW	coefficient of width dependence for width offset (in m ^WWN ). (Default = 0).
WWN	power of width dependence for width offset (Default = 1.0).
WWL	coefficient of length and width cross term for width offset (in m ^WWN+WLN ). (Default = 0).
LL	coefficient of length dependence for length offset (in m ^LLN ). (Default = 0).
LLN	power of length dependence for length offset (Default = 1.0).
LW	coefficient of width dependence for length offset (in m ^LWN ). (Default = 0).
LWN	power of width dependence for length offset (Default = 1.0).
LWL	coefficient of length and width cross term for length offset (in m ^LWN+LLN ). (Default = 0).
TNOM	parameter measurement temperature (in °C) - If no value is specified, the default value assigned to TNOM on the SPICE Options page of the Analyses Setup dialog will be used (Default = 27).
UTE	mobility temperature exponent (Default = -1.5).
KT1	temperature coefficient for threshold voltage (in Volts). (Default = -0.11).
KT1L	channel length dependence of the temperature coefficient for threshold voltage (in V*m). (Default = 0).
KT2	body-bias coefficient of Vth temperature effect (Default = 0.022).
UA1	temperature coefficient for UA (in m/V). (Default = 4.31e-9).
UB1	temperature coefficient for UB (in (m/V) ² ). (Default = -7.61e-18).
UC1	temperature coefficient for UC. For MOBMOD = 1 or 2, measured in m/V ² , Default = -5.6e-11 For MOBMOD = 3, measured in 1/V, Default = -0.056.
AT	temperature coefficient for saturation velocity (in m/s). (Default = 3.3e4).
PRT	temperature coefficient for RDSW (in Ω-μm). (Default = 0).
NJ	emission coefficient of junction (Default = 1).
XTI	junction current temperature exponent coefficient (Default = 3.0).
NOIA	noise parameter A (Default = 1e20 - NMOS; 9.9e18 - PMOS).
NOIB	noise parameter B (Default = 5e4 - NMOS; 2.4e3 - PMOS).
NOIC	noise parameter C (Default = -1.4e-12 - NMOS; 1.4e-12 - PMOS).
EM	saturation field (in V/m). (Default = 4.1e7).
AF	frequency exponent (Default = 1).
EF	flicker exponent (Default = 1).
KF	flicker noise parameter (Default = 0).
TOX	gate oxide thickness (in meters). (Default = 1.5e-8).
XJ	junction depth (in meters). (Default = 1.5e-7).
GAMMA1	body-effect coefficient near the surface (in V ^1/2 ). (See BSIM3-Related notes).
GAMMA2	body-effect coefficient in the bulk (in V ^1/2 ). (See BSIM3-Related notes).
NCH	channel doping concentration (in 1/cm ³ ). (Default = 1.7e17). (See BSIM3-Related notes).
NSUB	substrate doping concentration (in 1/cm ³ ). (Default = 6e16).
VBX	Vbs at which the depletion region width equals XT (in Volts). (See BSIM3-Related notes).
XT	doping depth (in meters). (Default = 1.55e-7).
LMIN	minimum channel length (in meters). (Default = 0).
LMAX	maximum channel length (in meters). (Default = 1.0).
WMIN	minimum channel width (in meters). (Default = 0).
WMAX	maximum channel width (in meters). (Default = 1.0).
BINUNIT	Bin unit scale selector (Default = 1).

The following is a list of parameters that can be stored in the associated model file, when using the EKV model:

Process Related Parameters
COX	gate oxide capacitance per unit area (in F/m ² ). (Default = 0.7e-3).
XJ	junction depth (in meters). (Default = 0.1e-6).
DW	channel width correction (in meters). (Default = 0).
DL	channel length correction (in meters). (Default = 0).
Basic Intrinsic Model Parameters
VTO	long-channel threshold voltage (in Volts). (Default = 0.5).
GAMMA	body effect parameter (in V ^1/2 ). (Default = 1.0).
PHI	bulk Fermi potential (*2) (in Volts). (Default = 0.7).
KP	transconductance parameter (in A/V ² ). (Default = 50.0e-6).
E0 (EO)	mobility reduction coefficient (in V/m). (Default = 1.0e12).
UCRIT	longitudinal critical field (in V/m). (Default = 2.0e6).
Optional Parameters
TOX	oxide thickness (in meters).
NSUB	channel doping (in cm ^-3 ).
VFB	flat-band voltage (in Volts).
UO	low-field mobility (in cm ² /Vs).
VMAX	saturation velocity (in m/s).
THETA	mobility reduction coefficient (in 1/V). (Default = 0).
Channel Length Modulation and Charge Sharing Parameters
LAMBDA	depletion length coefficient (channel length modulation). (Default = 0.5).
WETA	narrow-channel effect coefficient. (Default = 0.25).
LETA	short-channel effect coefficient. (Default = 0.1).
Reverse Short-Channel Effect Parameters
Q0 (QO)	reverse short-channel effect peak charge density (in As/m ² ). (Default = 0).
LK	reverse short-channel effect characteristic length (in meters). (Default = 0.29e-6).
Impact Ionization Related Parameters
IBA	first impact ionization coefficient (in 1/m). (Default = 0).
IBB	second impact ionization coefficient (in V/m). (Default = 3.0e8).
IBN	saturation voltage factor for impact ionization. (Default = 1.0).
Intrinsic Model Temperature Parameters
TCV	threshold voltage temperature coefficient (in V/K). (Default = 1.0e-3).
BEX	mobility temperature exponent. (Default = -1.5).
UCEX	longitudinal critical field temperature exponent. (Default = 0.8).
IBBT	temperature coefficient for IBB (in 1/K). (Default = 9.0e-4).
Flicker Noise Parameters
KF	flicker noise coefficient. (Default = 0).
AF	flicker noise exponent. (Default = 1).
Setup Parameters
NQS	non-quasi-static (NQS) operation switch. (Default = 0).
SATLIM	ratio defining the saturation limit. (Default = exp(4)).
Additional Parameters
LEVEL	model index (Default = 1).
TNOM	parameter measurement temperature (in °C) - If no value is specified, the default value assigned to TNOM on the SPICE Options page of the Analyses Setup dialog will be used (Default = 27).
IS	bulk junction saturation current (in Amps). (Default = 1.0e-14).
JS	bulk junction saturation current per square meter of junction area (in Amps/m ² ).
JSW	sidewall saturation current per unit length (in A/m). (Default = 0).
N	bulk p-n emission coefficient. (Default = 1).
CBD	zero-bias B-D junction capacitance (in Farads). (Default = 0).
CBS	zero-bias B-S junction capacitance (in Farads). (Default = 0).
CJ	zero-bias bulk junction bottom capacitance per square meter of junction area (in Farads/m ² ). (Default = 0).
CJSW	zero-bias bulk junction sidewall capacitance per meter of junction perimeter (in Farads/meter). (Default = 0).
MJ	bulk junction bottom grading coefficient. (Default = 0.5).
MJSW	bulk junction sidewall grading coefficient. (Default = 0.33).
FC	coefficient for forward-bias depletion capacitance formula. (Default = 0.5).
PB	bulk junction potential (in Volts). (Default = 0.8).
PBSW	built-in potential of source drain junction sidewall (in Volts). (Default = 1).
TT	bulk p-n transit time (in seconds). (Default = 0).
CGSO	Gate-Source overlap capacitance per meter channel width (in F/m). (Default = 0).
CGDO	Gate-Drain overlap capacitance per meter channel width (in F/m). (Default = 0).
CGBO	Gate-Bulk overlap capacitance per meter channel length (in F/m). (Default = 0).
RD	drain ohmic resistance (in Ohms). (Default = 0).
RS	source ohmic resistance (in Ohms). (Default = 0).
RSH	Drain and Source diffusion sheet resistance (in Ohms). (Default = 0).
RSC	source contact resistance (in Ohms). (Default = 0).
RDC	drain contact resistance (in Ohms). (Default = 0).
XTI	drain, source junction current temperature exponent. (Default = 0).
TR1	first-order temperature coefficient for drain, source series resistance (in °C ^-1 ). (Default = 0).
TR2	second-order temperature coefficient for drain, source series resistance (in °C ^-1 ). (Default = 0).
ACM	area calculation model. (Default = 0).
CJGATE	zero-bias gate-edge sidewall junction capacitance (in F/m). If no value is specified, the value assigned to CJSW will be used. This parameter is only used when ACM = 3. It is ignored otherwise.
GEO	shared geometry parameter. (Default = 0). This parameter is only used when ACM = 3. It is ignored otherwise.
HDIF	length of heavily doped diffusion (in m). (Default = 0). This parameter is only used when ACM = 2 or 3. It is ignored otherwise.
LD	lateral diffusion into channel (in m). (Default = 0).
LDIF	length of lightly doped diffusion near gate (in m). (Default = 0).
SCALM	model scaling factor. (Default = 1).
UPDATE	selects effective drain and source resistance model. (Default = 0). This parameter is only used when ACM = 1. It is ignored otherwise.
WMLT	width diffusion layer shrink reduction factor. (Default = 1).

Notes

General

The Simulator supports the following MOSFET device models, which differ only in their formulation of the I-V characteristic:

Shichman-Hodges (LEVEL=1)
MOS2 (LEVEL=2)
MOS3 (LEVEL=3)
BSIM (LEVEL=4)
BSIM2 (LEVEL=5)
MOS6 (LEVEL=6)
BSIM3 (LEVEL=7)
EKV (LEVEL=8)

The LEVEL parameter is used to specify which model to use. It is declared at the start of the parameter values list, entered in the associated model file. If no LEVEL parameter is declared, the default Schichman-Hodges model will be used.
The Bulk (substrate) node is connected, by default, to the Source node.
If any of the component-level Length, Width, Drain Area or Source Area parameters are not specified, default values will be used.
The values for the component-level NRD and NRS parameters are used to multiply the sheet resistance (RSH), in order to obtain an accurate representation of the parasitic series drain and source resistance of each transistor.
The values for the component-level parameters Initial D-S Voltage, Initial G-S Voltage and Initial B-S Voltage only apply if the Use Initial Conditions option is enabled on the Transient/Fourier Analysis Setup page of the Analyses Setup dialog.
The component-level Temperature parameter applies to LEVEL 1,2,3,6 & 8 MOSFET models (not BSIM type models).
The link to the required model file (*.mdl) is specified on the Model Kind tab of the Sim Model dialog. The Model Name is used in the netlist to reference this file.
Where a parameter has an indicated default (as part of the SPICE model definition), that default will be used if no value is specifically entered. The default should be applicable to most simulations. Generally you do not need to change this value.

BSIM/BSIM2-Related

The BSIM and BSIM2 models are designed to be used with a process characterization system. This system is responsible for providing all parameter information (values) automatically through the use of a process file and therefore no default parameter values are specified. As a consequence, all parameters are required to be specified and the absence of any will result in an error.
If the XPART parameter is set to 0, a 40/60 drain/source charge partition in saturation is selected. If this parameter is set to 1, a 0/100 drain/source charge partition is selected.
Certain model parameters (those marked with an asterisk in the BSIM/BSIM2 list of parameters) also have corresponding parameters dependent on length and width. For more information on these and other aspects of the MOSFET models, consult the SPICE reference manual.

BSIM3-Related

The following charge partition schemes are supported, selectable based on the value entered for the XPART parameter:

XPART = 0 - a 0/100 drain/source charge partition os selected
XPART = 0.5 - a 50/50 drain/source charge partition os selected
XPART = 1 - a 40/60 drain/source charge partition os selected.

If no value is specified for one of the following parameters, it will be calculated:

VTH0
K1
K2
CGSO
CGDO
CF
GAMMA1
GAMMA2
NCH
VBX

For details of the calculations involved, refer to the BSIM3v3 User Manual.
The following BSIM3 model parameters are not supported in Altium Designer:

JSSW	side wall saturation current density.
CGS1	light doped source-gate region overlap capacitance.
CGD1	light doped drain-gate region overlap capacitance.
VFB	flat-band volatge parameter.

EKV-Related

The EKV MOSFET model was developed by the Electronics Laboratory (LEG) of the Swiss Federal Institute of Technology (EPFL). The model used in Altium Designer is version 2.6.
The following EKV model parameters are not supported in Altium Designer:

M or NP	parallel multiple device number.
N or NS	series multiple device number.
AVTO	area related threshold voltage mismatch parameter.
AKP	area related gain mismatch parameter.
AGAMMA	area related body effect mismatch parameter.
XQC	charge/capacitance model selector.

For more detailed information on model equations associated with the EKV MOSFET, search the site http://ekv.epfl.ch/ for the document The EPFL-EKV MOSFET Model Equations for Simulation.

Examples

Consider the MOSFET in the above image, with the following characteristics:

Pin1 (Drain) is connected to net D
Pin2 (Gate) is connected to net G
Pin3 (Source) is connected to net S
The substrate node (Bulk) is connected to Pin3 (the Source node).
Designator is Q1
The linked simulation model file is NMOS3.mdl.

If no values are entered for the parameters in the Sim Model dialog, the entries in the SPICE netlist would be:

*Schematic Netlist: MQ1 D G S S NMOS3 . . *Models and Subcircuit: .MODEL NMOS3 NMOS(LEVEL=3)

In this case, there are no parameter values specified in the Sim Model dialog. In the model file, there is only the LEVEL parameter specified, corresponding to the use of the MOS3 model. The default values for all other parameters inherent to the model will be used.

PSpice Support

Of the existing MOSFET device models, the following are not supported with respect to PSpice compatibility:

BSIM3 model version 2.0

For the other supported MOSFET device models, many of the parameters that can be included in a linked model file are common to both Spice3f5 and PSpice. Those that are supported can be found in the previous section, Parameters (definable within model file).

The following PSpice-based parameters are not supported for this device type.

GDSNOI	channel shot noise coefficient (use with NLEV=3)
JSSW	bulk p-n saturation sidewall current/length
L	channel length
N	bulk p-n emission coefficient
NLEV	noise equation selector
PBSW	bulk p-n sidewall potential
RB	bulk ohmic resistance
RDS	drain-source shunt resistance
RG	gate ohmic resistance
TT	bulk p-n transit time
W	channel width