LEVEL 8 HiCUM Model
What is the HiCUM Model?
HiCUM is an advanced transistor model for bipolar transistors, with a primary emphasis on circuit design for highspeed/highfrequency applications. HiCUM development was spurred by the SPICE GummelPoon model's (SGPM) inadequate level of accuracy for highspeed largesignal transient applications and the required highcollector current densities. Other major disadvantages of the SGPM are:

A lack of sufficient physical background

Poor descriptions of base resistance and junction capacitances in the regions of interest

Inadequate description of both Si and IIIV materialbased HBTs
The HiCUM model is implemented with LEVEL 8 in Hspice.
HiCUM Model Advantages
Major features of HiCUM are:

Accurate description of the highcurrent operating region (including quasisaturation and saturation).

Distributed modelling of external basecollector region.

Proper handling of emitter periphery injection and charge storage .

Internal base resistance as a function of operating point (conductivity modulation and emitter current crowding), and emitter geometry.

Sufficiently physical model equations allowing predictions of temperature and process variations, as well as scalability, even at high current densities.

Parasitic capacitances, independent on operating point, are available in the equivalent circuit, representing baseemitter and basecollector oxide overlaps, that become significant for smallsize transistors.

Weak avalanche breakdown is available.

Selfheating effects are included. Nonquasistatic effects, resulting in a delay of collector current AND stored minority charge, are modelled as function of bias.

Collector current spreading is included in minority charge and collector current formulation.

Extensions for gradedbase SiGe HBTs have been derived using the Generalized Integral ChargeControl Relation (GICCR); the GICCR also permits modelling of HBTs with (graded) bandgap differences within the junctions.

Baseemitter tunneling model is available (e.g., for simulation of varactor leakage).

Simple parasitic substrate transistor is included in the equivalent circuit.

Simple parallel RC network taking into account the frequency dependent coupling between buried layer and substrate terminal.

Parameter extraction is closely related to the process enabling parametric yield simulation; parameter extraction procedure and list of test structures are available; HiCUM parameters can be determined using standard measurement equipment and mostly simple, decoupled extraction procedures.

Simple equivalent circuit and numerical formulation of model equations result in easy implementation and relatively fast execution time.
These features together with the choice of easily measurable basic variables such as junction capacitances and transit time provide  compared to the SGPM  high accuracy for digital circuit, smallsignal highfrequency and, in particular, highspeed largesignal transient simulation. Also, HiCUM is laterally scaleable over a wide range of emitter widths and lengths up to high collector current densities; the scaling algorithm is generic and has been applied to the SGPM (within its validity limits).
In summary, HiCUM's major advantages over other bipolar compact models are:

Scalability

Processbased and relatively simple parameter extraction

Predictive capability in terms of process and layout variations

Fairly simple numerical formulation facilitating easy implementation and resulting in still reasonable simulation time compared to the (too) simple SGPM at high current densities
StarHspice HiCUM Model vs. Public HiCUM Model
Difference Highlights
To maintain flexibility, the StarHspice LEVEL 8 HiCUM model uses FBCS, IS, KRBI, MCF, MSR, and ZETACX as additional model parameters. See Other Parameters.
NOTE: Selfheating is not supported in the 2000.4 StarHspice release.
Model Implementation
Model Parameters
Parameter

Unit

Default

Description

LEVEL


9

HiCUM BJT level in Hspice

TREF

C

26.85

Temperature in simulation

Internal Transistors
Transfer Current Parameters
Parameter

Unit

Default

Factor

Description

C10

A^2s

3.76e32

M^2

Constant(IS*QP0)

Qp0

As

2.78e14


Zerobias hole charge

ICH

A

2.09e0Z


Highcurrent correction for 2D/3D

HFC



1.0


Weighting factor for Qfc (mainly for HBTs)

HFE



1.0


Weighting factor for Qef in HBTs

HJCI



1.0


Weighting factor for Qjci in HBTs

HJEI



0.0


Weighting factor for Qjei in HBTs

ALIT



0.45


Factor for additional delay time of iT

BE Depletion Capacitance Parameters
Parameter

Unit

Default

Factor

Description

VDEI

V

0.95


Builtin voltage

CJEI0

F

8.11e15


Zerobias value

ZEI



0.5


Exponent coefficient

ALJEI



1.8


Ratio of max. to zerobias value

BC Depletion Capacitance Parameters
Parameter

Unit

Default

Factor

Description

CJCI0

F

1.16e15

M^2

Zerobias value

VDCI

V

0.8


Builtin voltage

ZCI



0.333


Exponent coefficient

VPTCI

V

416


Punchthrough voltage (=q Nci w^2ci /(2epsilion))

Forward Transit Time Parameters
Parameter

Unit

Default

Factor

Description

T0

s

4.75e12


Low current transit time at V B'C'=0

DT0H

s

2.1e12


Time constant for base and BC SCR width modulation

TBVL

s

40e12


Voltage for modeling carrier jam at low VC'E'

TEF0

s

1.8e12


Storage time in neutral emitter

GTFE



1.4


Exponent factor for current dep. emitter transit time

THCS

s

3.0e11


Saturation time constant at high current densities

ALHC



0.75


Smoothing factor for current dep. C and B transit time

FTHC



0.6


Partitioning factor for base and collection portion

ALQF



0.225


Factor for additional delay time of Q_f

Critical Current Parameters
Parameter

Unit

Default

Factor

Description

RCI0

Ohm

127.8

1/M

Lowfield resistance of internal collector region

VLIM

V

0.7


Voltage separating ohmic and SCR regime

VPT

V

5.0


Epi punchthrough vtg. of BC SCR

VCES

V

0.1


Internal CE sat. vtg.

Inverse Transit Time Parameter
Parameter

Unit

Default

Factor

Description

TR

s

1.0e9


Time constant for inverse operation

Base Current Components Parameters
Parameter

Unit

Default

Factor

Description

IBEIS

A

1.16e20

M

BE saturation current

MBEI



1.015


BE saturation current

IREIS

A

1.16e6

M

BE recombination saturation current

MREI



2.0


BE recombination nonideality factor

IBCIS

A

1.16e20

M

BC saturation current

MBCI



1.015


BC nonideality factor

Weak BC Avalanche Breakdown Parameters
Parameter

Unit

Default

Factor

Description

FAVL

1/V

1.186


Prefactor for CB avalanche effect

QAVL

As

1.11e14

M

Exponent factor for CB avalanche effect

Internal Base Resistance Parameters
Parameter

Unit

Default

Factor

Description

RBI0

Ohm

0

1/M

Value at zerobias

FDQR0



0.0


Correction factor for modulation by BE abd BC SCR

FGEO



0.73


Geometry factor (value corresponding to long emitter stripe)

FQI



0.9055


Ratio of internal to total minority charge

FCRBI



0.0


Ratio of h.f. shunt to total internal capacitance.

Lateral Scaling
Parameter

Unit

Default

Factor

Description

LATB



3.765


Scaling factor for Qfc in 1_E

LATL



0.342


Scaling factor for Qfc in l_E direction

Peripheral Elements
BE Depletion Capacitance
Parameter

Unit

Default

Factor

Description

CJEP0

F

2.07e15

M

Zerobias value

VDEP

V

1.05


Builtin voltage

ZEP



0.4


Depletion coeff

ALJEP



2.4


Ratio of max. to zerobias value

Base Current
Parameter

Unit

Default

Factor

Description

IBEPS

A

3.72e21

M

Saturation current

MBEP



1.015


Nonideality factor

IREPS

A

1e30

M

Recombination saturation factor

MREP



2.0


Recombination nonideality factor

BE Tunneling
Parameter

Unit

Default

Factor

Description

IBETS

A

0

M

Saturation current

ABET



0.0


Exponent coefficient

External Elements
BC Capacitance
Parameter

Unit

Default

Factor

Description

CJCX0

F

5.393e15

M

Zerobias depletion value

VDCX

V

0.7


Builtin voltage

ZCX



0.333


Exponent coefficient

VPTCX

V

100


Punchthrough voltage

CCOX

F

2.97e15

M

Collector oxide capacitance

FBC



0.1526


Partitioning factor for C_BCX =C'_BCx+C"_BCx

BC Base Current Component
Parameter

Unit

Default

Factor

Description

IBCXS

A

4.39e20

M

Saturation current

MBCX



1.03


Nonideality factor

Other External Elements
Parameter

Unit

Default

Factor

Description

CEOX

F

1.13e15

M

Emitterbase isolation overlap cap

RBX

Ohm

0

1/M

External base series resistance

RE

Ohm

0

1/M

Emitter series resistance

RCX

Ohm

0

1/M

External collector series resistance

Substrate Transistor Parameters
Parameter

Unit

Default

Factor

Description

ITSS

A

0.0

M

Transfer saturation current

MSF



0.0


Nonideality factor (forward transfer current)

TSF



0.0


Minority charge storage transit time

ISCS

A

0.0

M

Saturation current of CS diode

MSC



0.0


Nonideality factor of CS diode

CollectorSubstrate Depletion Capacitance
Parameter

Unit

Default

Factor

Description

CJS0

F

3.64e14

M

Zerobias value of CS depletion cap

VDS

V

0.6


Builtin voltage

ZS



0.447


Exponent coefficient

VPTS

V

1000


Punchthrough voltage

Substrate Coupling Network
Parameter

Unit

Default

Factor

Description

RSU

Ohm

0

1/M

Substrate series resistance

CSU

F

0


Substrate capacitance from permittivity of bulk material

Noise Parameters
Parameter

Unit

Default

Factor

Description

KF



1.43e8


Flicker noise factor (no unit only for AF=2! )

AF



2.0


Flicker noise exponent factor

KRBI



1.17


Factor for internal base resistance

Temperature Dependence Parameters
Parameter

Unit

Default

Factor

Description

VGB

V

1.17


Bandgapvoltage

ALB

1/K

6.3e3


Relative temperature coefficient of forward current gain

ALT0

1/K

0


Firstorder relative temperature coefficient of TEF0

KT0

1/K

0


Secondorder relative temperature coefficient of TEF0

ZETACI



1.6


Temperature exponent factor RCI0

ALVS

1/K

1e3


Relative temperature coefficient of saturation drift velocity

ALCES

1/K

0.4e3


Relative temperature coefficient of VCES

ZETARBI



0.588


Temperature exponent factor of RBI0

ZETARBX



0.2060


Temperature exponent factor of RBX

ZETARCX



0.2230


Temperature exponent factor of RCX

ZETARE



0


Temperature exponent factor of RE

ALFAV

1/K

8.25e5


Relative temperature coefficient for avalanche breakdown

ALQAV

1/K

1.96e4


Relative temperature coefficient for avalanche breakdown

SelfHeating Parameters
Parameter

Unit

Default

Factor

Description

RTH

K/W

0

1/M

Thermal resistance (not supported)

CTH

Ws/K

0

M

Thermal resistance (not supported)

Other Parameters
Parameter

Unit

Default

Factor

Description

FBCS



1.0


Determine external BC capacitance partitioning

IS

1.0

A


Ideal saturation current

KRBI



1.0


Noise analysis of internal resistance

MCF



1.0


Nonideality factor of reverse current between base and collector. VT=VT*MCF

MSR



1.0


Nonideality factor of reverse current in substrate transistor. VT=VT*MSR

ZETACX



1.0


Temperature exponent factor (epilayer)

Netlist Input and Output Formats
This section provides the syntax for LEVEL 8 and an example of an input netlist and output format.
Syntax
Qxxx nc nb ne <ns> mname <area> <M=val> <DTEMP=val>
Qxxx

BJT element name

nc

Collector terminal node

nb

Base terminal node

ne

Emitter terminal node

ns

Substrate terminal node

mname

BJT model name reference

area

Emitter area multiplying factor which affects currents, resistances and capacitances(default=1)

M

Multiplier to simulate multiple BJTs in parallel

DTEMP

Difference between the element temperature and the circuit temperature in Celsisu. (Default=0.0)

Example
This is an example of a BJT Q1 with collector, base and emitter and substrate connected to nodes 1, 2 and 3 and 4, where the BJT model is given by QM:
Q1 1 2 0 4 QM area=1*0.5*5 dtemp=0.002
Circuit Diagram
Input Netlist
.DATA test_data vbe vce vsub
0.0 0.0 0.0
0.1 0.0 0.0
0.2 0.0 0.0
0.3 0.0 0.0
0.4 0.0 0.0
0.5 0.0 0.0
0.6 0.0 0.0
0.7 0.0 0.0
0.8 0.0 0.0
0.9 0.0 0.0
1.0 0.0 0.0
.ENDDATA
.OPTIONS
.TEMP 26.85
VIN 2 0 vbe
VC 1 0 vce
VS 4 0 vsub
VE 3 0 0
Q1 1 2 3 4 hicum
.DC data= test_data
.PRINT DC I(VIN) i2(q1) I(VC) i1(q1) I(VCS) i4(q1)
.MODEL hicum NPN LEVEL=8
+ tref = 26.85
+ c10=.3760000E31 qp0=.2780000E13 ich=.2090000E01
+ hfc=.1000000E+01
+ hfe=1.0000000E+00 hjei=.000000E+00
+ hjci=.100000E+01 tr=1.00000000E9
+ cjei0=.81100E14 vdei=.950000E+00 zei=.5000000E+00
+ aljei=.18000E+01
+ cjci0=.11600E14 vdci=.800000E+00 zci=.3330000E+00
+ vptci=.41600E+03
+ rci0=.127800E+03 vlim=.700000E+00 vpt=.5000000E+01
+ vces=.100000E+00
+ t0=.47500000E11 dt0h=.210000E11 tbvl=.400000E11
+ tef0=.180000E11 gtfe=.140000E+01 thcs=.300000E10
+ alhc=.750000E+00
+ fthc=.600000E+00
+ latb=.376500E+01 latl=.342000E+00 fqi=.9055000E+00
+ alit=.450000E+00 alqf=.225000E+00
+ favl=.118600E+01 qavl=.111000E13 alfav=.82500E04
+ alqav=.19600E03
+ ibeis=.11600E19 mbei=.101500E+01 ibeps=.10000E29
+ mbep=.200000E+01
+ ireis=.11600E15 mrei=.200000E+01 ireps=.10000E29
+ mrep=.200000E+01
+ rbi0=.000000E+00 fdqr0=.00000E+00 fgeo=.730000E+00
+ fcrbi=.00000E+00
+ cjep0=.00000E+00 vdep=.105000E+01 zep=.4000000E+00
+ aljep=.24000E+01
+ ceox=.000000E+00
+ cjcx0=.00000E+00 vdcx=.700000E+00 zcx=.3330000E+00
+ vptcx=.10000E+03
+ ccox=.000000E+00 fbc=.1526000E+00
+ ibcxs=.10000E29 mbcx=.200000E+01 ibcis=.11600E19
+ mbci=.101500E+01
+ cjs0=.000000E+00 vds=.6000000E+00 zs=.44700000E+00
+ vpts=.100000E+04
+ rcx=.0000000E+00 rbx=.0000000E+00 re=.00000000E+00
+ kf=.00000000E+00 af=.00000000E+00
+ vgb=.1170000E+01 alb=.6300000E02 alt0=.000000E+00
+ kt0=.0000000E+00
+ zetaci=.1600E+01 alvs=.100000E02 alces=.40000E03
+ zetarbi=0.5880E+00 zetarcx=0.2230E+00
+ zetarbx=0.2060E+00 zetare=0.0000E+00
+ rth=0.0 cth=0.0
+ ibets=.00000E+00 abet=.000000E+00
+ itss=.000000E+00 msf=.0000000E+00 tsf=0.000000E+00
+ iscs=.000000E+00
+ msc=.0000000E+00
+ rsu=.0000000E+00 csu=.0000000E+00
.END
StarHspice Manual  Release 2001.2  June 2001