In this appendix, command codes used in TCAD Sprocess, TCAD Sdevice simulators are given. Note that here “hGe” stands for hbody only, not the total germanium thickness.
line x loc= 0 tag=SiTop spacing=50<nm>
line x loc= 300<nm> tag=SiBottom spacing=50<nm>
line y loc= 0 tag=SiLeft spacing=50<nm>
line y loc= $Wtot tag=SiRight spacing=50<nm>
region silicon xlo=SiTop xhi=SiBottom ylo=SiLeft yhi=SiRight
init concentration=1e15 field=Boron !DelayFullD
mgoals on min.normal.size=2<nm> max.lateral.size=2<um> normal.growth.ratio=1.3
# PHYSICAL MODELS FOR GERMANIUM
pdbSetDouble ImplantData Germanium AtomicMass 72.61 pdbSetDouble ImplantData Germanium AtomicNumber 32 pdbSetDouble Germanium LatticeConstant 5.64613
pdbSetDouble Germanium LatticeDensity 4.41e22
pdbSetDouble Germanium AmorpGamma 1.0
pdbSetDouble Germanium AmorpDensity 1.1e22
pdbSetDouble Germanium AmorpThreshold 1.1e22
pdbSetDouble Germanium LatticeSpacing [expr pow(1/4.41e22,1.0/3.0)]
pdbSetString Germanium LatticeType Zincblende
pdbSetDouble Germanium MassDensity 5.35
pdbSetBoolean Germanium Amorphous 0
pdbSetString Germanium LatticeAtom COMPOSITION pdbSetString Germanium Composition Component0 Name Germanium pdbSetDouble Germanium Composition Component0 StWeight 1
pdbSetDouble Germanium CompoundNumber 1
pdbSetBoolean Germanium ElectronicStoppingLocal 1
pdbSetDouble Germanium SurfaceDisorder 5e‐4
# NUMERICAL PARAMETERS FOR TaurusMC (please consult manual)
pdbSet MCImplant TrajectoryReplication 1
pdbSet MCImplant TrajectorySplitting 1
pdbSetDouble Germanium Phosphorus MaxSplits 8.0 pdbSetDouble Germanium Phosphorus MaxSplitsPerElement 1.0
pdbSetDouble Germanium Boron MaxSplits 8.0
pdbSetDouble Germanium Boron MaxSplitsPerElement 1.0
pdbSetDouble Germanium Arsenic MaxSplits 8.0
pdbSetDouble Germanium Arsenic MaxSplitsPerElement 1.0
# Monte Carlo Implant paramerters implanted species (TaurusMC) pdbSetDouble Germanium Phosphorus amor.par 1.0 pdbSetDouble Germanium Phosphorus casc.amo 1.0
pdbSetDouble Germanium Phosphorus disp.thr 15
pdbSetDouble Germanium Phosphorus casc.dis 15
pdbSetDouble Germanium Phosphorus surv.rat 0.75 pdbSetDouble Germanium Phosphorus casc.sur 0.75 pdbSetDouble Germanium Phosphorus MCVFactor 1.0 pdbSetDouble Germanium Phosphorus MCDFactor 1.0 pdbSetDouble Germanium Phosphorus MCIFactor 1.0
pdbSetDouble Germanium Boron amor.par 1.0
pdbSetDouble Germanium Boron casc.amo 1.0
pdbSetDouble Germanium Boron disp.thr 15
pdbSetDouble Germanium Boron casc.dis 15
pdbSetDouble Germanium Boron surv.rat 0.225
pdbSetDouble Germanium Boron casc.sur 0.225
pdbSetDouble Germanium Boron MCVFactor 1.0
pdbSetDouble Germanium Boron MCDFactor 1.0
pdbSetDouble Germanium Boron MCIFactor 1.0
pdbSetDouble Germanium Boron LSS.pre 1.25
pdbSetDouble Germanium Boron nloc.exp 0.075
pdbSetDouble Germanium Boron nloc.pre 0.44
pdbSetDouble Germanium Boron casc.sat 0.02
pdbSetDouble Germanium Boron sat.par 0.02
# THESE PARAMETERS makes B only partially amorphizing in
Germanium,
# damage saturates when 2% of lattice atoms have been # displaced. This number is based on LIMITED SIMS data # and should be considered an estimate.
pdbSetDouble Germanium Arsenic amor.par 1.0
pdbSetDouble Germanium Arsenic casc.amo 1.0
pdbSetDouble Germanium Arsenic disp.thr 15
pdbSetDouble Germanium Arsenic casc.dis 15
pdbSetDouble Germanium Arsenic surv.rat 2
pdbSetDouble Germanium Arsenic casc.sur 2
pdbSetDouble Germanium Arsenic MCVFactor 1.0
pdbSetDouble Germanium Arsenic MCDFactor 1.0
pdbSetDouble Germanium Arsenic MCIFactor 1.0
pdbSetDouble Germanium Arsenic LSS.pre 1
pdbSetDouble Germanium Arsenic nloc.exp 0.075
pdbSetDouble Germanium Arsenic nloc.pre 0.5
###1_oxide_pattertn
deposit material= {Oxide} type=isotropic thickness=$hOX
etch material= {Oxide} type=anisotropic thickness=@hov@ mask=hov etch material= {Oxide} type=anisotropic thickness=[expr (@hGe@+0.001)] mask=hGe
###2_silicon_etch_back
# X1 0
define Y1 [expr @wov@+$garden]
define Y2 [expr $Y1+@hRec@/tan($theta)]
define Y3 [expr $Wtot‐$Y2]
define Y4 [expr $Wtot‐$Y1]
etch material= {Silicon} type=polygon polygon= {0 $Y1 @hRec@ $Y2 @hRec@ $Y3 0 $Y4 0 $Y1 }
###3_Germanium Growth
deposit material= {Germanium} type=fill coord=‐$hOX
###4_N++ implant (masked)
mask clear
mask name=N_imp left=‐1<nm> right=$imp_long negative
mask name=N_imp left=[expr ($Wtot‐$garden)] right=[expr ($Wtot+0.001)] negative
deposit material= {Nitride} type=anisotropic thickness=1000<nm> mask=N_imp implant Phosphorus dose=5e14<cm‐2> energy=80<keV> sentaurus.mc info=1
strip Nitride
###5_P++ implant (masked)
mask clear
mask name=P_imp left=‐1<nm> right=$garden negative
mask name=P_imp left=[expr ($Wtot‐$imp_long)] right=[expr ($Wtot+0.001)] negative deposit material= {Nitride} type=anisotropic thickness=1000<nm> mask=P_imp
implant Boron dose=5e14<cm‐2> energy=30<keV> sentaurus.mc info=1
strip Nitride
select Germanium z=(Phosphorus+Boron+@Dpeak@) name=TotalConcentration store select Silicon z=(Phosphorus+Boron) name=TotalConcentration store "
} else {
puts "
select Germanium z=(Phosphorus+Boron+@Dpeak@*exp(‐(@hRec@‐x)/0.02))
name=TotalConcentration store
select Silicon z=(Phosphorus+Boron) name=TotalConcentration store "
}
)!
###6_Contact formation #contact mask
mask clear
mask name=contact left=‐1<nm> right=[expr ($garden+0.05)]
mask name=contact left=[expr ($garden+0.05+0.35)] right=[expr ($Wtot‐($garden+0.05)‐0.35)]
mask name=contact left=[expr ($Wtot‐($garden+0.05))] right=[expr ($Wtot+0.001)]
deposit material= {Oxide} type=anisotropic thickness=250<nm>
etch material= {Oxide} type=anisotropic thickness=251<nm> mask=contact deposit material= {Aluminum} type=fill coord=[expr (‐1*($hOX+0.25))]
contact name=anode Aluminum x=[expr (‐1*($hOX+0.1))] y=[expr ($garden+0.05+0.1)] replace point contact name=cathode Aluminum x=[expr (‐1*($hOX+0.1))] y=[expr ($Wtot‐($garden+0.05+0.1))]
replace point
select z=(1e12/($sigmaX*sqrt(2*3.14159))*exp(‐
(x+$rX)*(x+$rX)/(2*$sigmaX*$sigmaX))*1/($sigmaY*sqrt(2*3.14159))*exp(‐(y‐$rY)*(y‐
Sdevice for IV
* output files:
Plot= "@tdrdat@"
*‐‐Temperature *‐‐Generation/Recombination
SRHRecombination Auger
*OpticalGeneration *OpticalIntensity
*‐ Creating initial solution
){ Coupled(Iterations=15 ) { Poisson Electron Hole} Plot (FilePrefix =
"n@node@_Dark_05" Time= (0.5))}
Goal { ModelParameter="Optics/OpticalGeneration/ReadFromFile/Scaling"
value=@Iphg@ }
){ Coupled(Iterations=15 ) { Poisson Electron Hole} Plot (FilePrefix =
"n@node@_Light_05" Time= (0.75))}
Sdevice for C‐V
Parameter="/imec/users/hellings/public/Doctoraat/TCAD/otherprojects/tables/Jan2010/Germani um_hellings_v2.par"
} Physics {
Mobility ( DopingDep)
Recombination (
Sdevice for transient
* output files:
Plot= "@tdrdat@"
*OpticalGeneration *OpticalIntensity
*‐ Ramp to negative bias
Quasistationary(
InitialStep=0.25 Increment=1.2 Decrement=4 MinStep=1e‐4 MaxStep=1
Goal { Name="anode" Voltage=‐0.5 }
){ Coupled(Iterations=15 ) { Poisson Electron Hole} Plot (FilePrefix =
"n@node@_Dark_05" Time= (0.5))}
NewCurrentFile="transient_"
Transient (
InitialTime = 0 FinalTime = 3e‐9 InitialStep=1 MaxStep=1e‐11
Bias{ ModelParameter="Optics/OpticalGeneration/ReadFromFile/Scaling" value=( 1 at 0, 1 at 0.99e‐9, 1e15 at 1e‐9, 1e15 at 1.99e‐9, 1 at 2e‐9, 1 at 2.99e‐9) }
) { Coupled { Poisson Electron Hole } }
}
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