powerex21.in : 3D Mixed-Mode Simulation of Current Filaments in Multicell IGBT
Requires: VictoryProcess3D / VictoryDevice3D
Minimum Versions: Victory Process 7.76.1.R, Victory Mesh 1.9.0.R, Victory Device 1.20.0.R
When an IGBT is turned on in the presence of a short-circuit in an output circuit for a period of time, it can dissipate power in the form of heat to such an extent that current filaments evolve in a localized area within the IGBT device. The heating effects of current filaments are destructive and thus should not be allowed to arise during a short-circuit operation of an IGBT.
In this example, the 3D mixed-mode short-circuit simulation is performed on an IGBT composed of 8 cells to demonstrate the occurrence of current filaments in multicell IGBT.
The 8-cell IGBT structure is constructed in cell mode of Victory Process by joining 8 duplicates of the IGBT single cell together using the parameter mirror on the export statement. Each IGBT single cell has a width of 1um and features a 1.3 kV trench-gate design with a field-stop layer (n-buffer).
Short-circuit testing is conducted with a test circuit consisting of a vc 650V DC power supply in series with a 10-mohm resistor rs and a 10-nH inductor ls . A vg gate pulse generator in series with a 10-ohm resistor rg generates a 15V pulse in 10 ns with a pulse length of 10 us.
It is assumed that the bottom collector electrode of the IGBT is maintained at an ambient temperature of 300 K via a thermal contact with a thermal resistance of 0.3 cm2.K/W ( thermcontact name=collector ext.temp=300 alpha=1/0.3 ).
As the mixed-mode simulation starts from an initial DC voltage supply of 650V, a Victory Device solution powerex21_1.str for the IGBT device adevice at a collector-to-emitter voltage of 650V is first obtained from the stand-alone Victory Device simulation and then loaded into the mixed-mode part of the input deck with .options loadsolutions for use as an initial guess.
Victory Device utilizes a set of physical models for the non-isothermal ( lat.temp self-heating) simulation including klassen low-field doping-dependent mobility , fldmob lateral electric field-dependent mobility, srh Shockley-Read-Hall recombination, hnsaug temperature and concentration dependence Auger recombination, and selb impact ionization. The pas MPI-based parallel direct solver specified in the Victory Device part of the mixed-mode input deck ( method device=adevice pas ) proves to greatly enhance Victor Device performance in terms of speed and robustness.
The simulation results give the short-circuit waveforms up to destruction of the IGBT at time t=7.57 us as evidenced by a sharp rising of temperature in conjunction with the establishment of current filaments. A 3D electron current density distribution at that device destruction time is captured and saved for visualization in TonyPlot with .save tsave="7.57us".
To load and run this example, select the Load button in DeckBuild > Examples. This will copy the input file and any support files to your current working directory. Select the Run button in DeckBuild to execute the example.
Input Deck
# (c) Silvaco Inc., 2022
go victoryprocess
set vge=15
set mirrorTimes=4
set Xhalf=pow(2,$'mirrorTimes')
option cartesian.spacing.ratio=1.5
set peakB1=2.0e17
set refB1=7.0e13
set distB1=3.0
set sigB1=$'distB1'/sqrt(-2*log($'refB1'/$'peakB1'))
set sigB1=floor(1000*(0.0005+$'sigB1'))/1000
set latB1=floor(1000*(0.0005+0.8*$'sigB1'))/1000
set peakB2=1e20
set refB2=7.0e13
set distB2=0.4
set sigB2=$'distB2'/sqrt(-2*log($'refB2'/$'peakB2'))
set sigB2=floor(1000*(0.0005+$'sigB2'))/1000
set latB2=floor(1000*(0.0005+0.8*$'sigB2'))/1000
set peakB3=2.0e17
set refB3=7.0e13
set distB3=6.0
set sigB3=$'distB3'/sqrt(-2*log($'refB3'/$'peakB3'))
set sigB3=floor(1000*(0.0005+$'sigB3'))/1000
set latB3=floor(1000*(0.0005+0.8*$'sigB3'))/1000
set peakP1=1e19
set refP1=7.0e13
set distP1=0.3
set sigP1=$'distP1'/sqrt(-2*log($'refP1'/$'peakP1'))
set sigP1=floor(1000*(0.0005+$'sigP1'))/1000
set latP1=floor(1000*(0.0005+0.8*$'sigP1'))/1000
init silicon depth=140 from="0,0" to="10,1" gasheight=3
line x loc=0 spac=0.2
line x loc=0.4 spac=0.1
line x loc=0.5 spac=0.1
line x loc=1.25 spac=0.75
line x loc=2 spac=0.1
line x loc=2.1 spac=0.1
line x loc=2.5 spac=0.4
line x loc=2.9 spac=0.1
line x loc=3.0 spac=0.1
line x loc=3.75 spac=0.75
line x loc=10 spac=5
line y loc=0 spac=1
line y loc=1 spac=1
line z loc=-1.5 spac=0.75
line z loc=-1 spac=0.5
line z loc=0 spac=0.25
line z loc=0.25 spac=0.25
line z loc=1.5 spac=0.5
line z loc=3 spac=0.25
line z loc=4.5 spac=1
line z loc=6 spac=0.5
line z loc=10 spac=1.5
line z loc=70 spac=20
line z loc=118 spac=4
line z loc=126 spac=5
line z loc=134 spac=2
line z loc=140 spac=4
doping phosphorus=7e13 silicon min=0 max=125
doping phosphorus=9.993e16 silicon min=118 max=134
doping boron=2e17 silicon min=134 max=140
specifymaskpoly maskid=1 istransparent=false \
p="0,0" p="2.1,0" p="2.1,1" p="0,1"
mask maskid=1
doping boron conc=$'peakB1' peak=0 sigma=$'sigB1' lateral=1e-5
strip barrier
specifymaskpoly maskid=2 istransparent=false \
p="0.4,0" p="1,0" p="1,1" p="0.4,1"
mask maskid=2
doping phosphorus conc=$'peakP1' peak=0 sigma=$'sigP1' lateral=$'latP1'
strip barrier
specifymaskpoly maskid=3 istransparent=false \
p="1,0" p="2.1,0" p="2.1,1" p="1,1"
mask maskid=3
doping boron conc=$'peakB2' peak=0 sigma=$'sigB2' lateral=$'latB2'
strip barrier
specifymaskpoly maskid=4 istransparent=false \
p="2.5,0" p="10,0" p="10,1" p="2.5,1"
mask maskid=4
doping boron conc=$'peakB3' peak=0 sigma=$'sigB3' lateral=1e-5
strip barrier
specifymaskpoly maskid=5 istransparent=false \
p="0,0" p="0.5,0" p="0.5,1" p="0,1"
specifymaskpoly maskid=5 istransparent=false add \
p="2,0" p="3,0" p="3,1" p="2,1"
mask maskid=5
etch silicon thickness=6 max
strip barrier
deposit oxide thickness=0 max
specifymaskpoly maskid=6 istransparent=false \
p="0,0" p="0.4,0" p="0.4,1" p="0,1"
specifymaskpoly maskid=6 istransparent=false add \
p="2.1,0" p="2.9,0" p="2.9,1" p="2.1,1"
mask maskid=6
etch oxide thickness=5.9 max
strip barrier
deposit aluminum thickness=0 max
specifymaskpoly maskid=6 electrode=gate \
p="0,0" p="0.4,0" p="0.4,1" p="0,1"
specifymaskpoly maskid=6 electrode=gate0v \
p="2.1,0" p="2.9,0" p="2.9,1" p="2.1,1"
electrodes maskid=6 aluminum
deposit oxide thickness=1 max
specifymaskpoly maskid=7 istransparent=false \
p="0.7,0" p="1.8,0" p="1.8,1" p="0.7,1"
mask maskid=7
etch oxide thickness=1 max
strip barrier
deposit aluminum thickness=0.5 max
specifymaskpoly maskid=8 istransparent=false \
p="0,0" p="10,0" p="10,1" p="0,1"
specifymaskpoly maskid=8 electrode=emitter \
p="0,0" p="10,0" p="10,1" p="0,1"
electrodes maskid=8 aluminum
electrodes name=collector substrate
save name=powerex21_vp_0
go victorymesh
load in=powerex21_vp_0
mirror axes="-x, +8x"
remesh conformal
save out=powerex21_0.str
#################################
# DC off 650V
#################################
go victorydevice
# intrinsic reference of silicon
set Ei=4.72280189
# device area (cm^2)
set scale=10e-4 * $'Xhalf' * 1e-4
mesh inf=powerex21_0.str
material silicon \
f.vsatn=powerex21.so f.vsatp=powerex21.so \
taun0=1e-5 taup0=3e-6 lt.taun=-1.5 lt.taup=-1.5
models print klassen fldmob bgn.kla srh hnsaug lat.temp
mobility alphp.cvt=0.719 feln.cvt=5.82e30 felp.cvt=2.0546e30 \
n.lcrit=1e-6 p.lcrit=1e-6 n.canali p.canali
impact selb
contact name=gate workfunc=0.2+$Ei
thermcontact name=collector alpha=1/0.3 ext.temp=300
method print pas norm.scaling.local carriers=2
output con.band val.band
solve init
solve prev
solve vcollector=0.01 prev
solve vcollector=0.1 vstep=0.1 vstop=1 name=collector
solve vcollector=2 vstep=1 vstop=10 name=collector
solve vstep=1.2 vmult vstop=450 name=collector
solve vstep=50 vstop=650 name=collector
save outf=powerex21_1.str
log off
#################################
# Short-Circuit by MixedMode
#################################
go victorydevice
# intrinsic reference of silicon
set Ei=4.72280189
# device area (cm^2)
set scale=10e-4 * $'Xhalf' * 1e-4
.begin
vg 1 0 0. pwl 0 0 0.01u $'vge' 10u $'vge' 10.01u 0 15u 0
rg 2 1 10
adevice 2=gate 3=emitter 4=collector 7=gate0v width=1/$scale infile=powerex21_1.str
vs1 3 0 0.
vs2 7 0 0.
ls 5 4 10nH
rs 6 5 10m
vc 6 0 650
.nodeset v(1)=0. v(2)=0. v(3)=0. v(4)=0. v(5)=650. v(6)=650. v(7)=0.
.options print relpot m2ln m2ln.tr loadsolutions noshift temp=300 m2ln.cutback
.numeric amp.precond elec.parallel.num=4
.save outfile=powerex21 master=powerex21 tsave="7.57us"
.log outfile=powerex21_0
.tran 1ns 7.57u
.end
material device=adevice silicon \
f.vsatn=powerex21.so f.vsatp=powerex21.so \
taun0=1e-5 taup0=3e-6 lt.taun=-1.5 lt.taup=-1.5
models device=adevice klassen fldmob bgn.kla srh hnsaug lat.temp
mobility device=adevice alphp.cvt=0.719 feln.cvt=5.82e30 felp.cvt=2.0546e30 \
n.lcrit=1e-6 p.lcrit=1e-6 n.canali p.canali
impact selb
contact device=adevice name=gate workfunc=0.2+$Ei
thermcontact device=adevice name=collector ext.temp=300 alpha=1/0.3
method device=adevice pas norm.scaling.local block.tran
output con.band val.band errors
probe device=adevice j.electron v.mag x=0 z=118 name="Jec"
probe device=adevice j.hole v.mag x=0 z=118 name="Jhc"
go victorydevice
tonyplot powerex21_0_tr.log -set powerex21_0.set
tonyplot3d powerex21_tr_1_adevice.str -set powerex21_1.set
quit
