Gamma radiation example in Sentaurus TCAD

[majkl85]

Hello all,

I have just joined this group - that is a very good idea to build up a community around the TCAD topic, as sometimes it is very hard to find valuable and precise information about the available tools.

As to the subject, recently I was trying to perform a gamma radiation tolerance simulations in Sentaurus TCAD, but following the steps described in user's guide didn't bear any good results. Does anyone of you have any example of a working sdevice input file involving gamma radiation tests of any form?

Hopefully waiting for any kind of help on this,
Mike

 

[chinmoy.khaund]

File {
Grid = "@grid@"
Doping = "@doping@"
Param = "@parameter@"
Output = "@log@"
* Plot = "@dat@"
Current = "@plot@"
}


Physics {
EffectiveIntrinsicDensity( Nobandgapnarrowing )
Recombination( SRH )
#if @<DOSERATE>@ != 0
* Irradiation time 20 seconds at 10krad/s or 25krad/s
Radiation(DoseRate=@<DOSERATE>@ DoseTime=(1,21) doseTsigma=0.2)
#endif
}

Physics (Material=Silicon) {
Mobility( DopingDependent HighFieldsat Enormal )
EffectiveIntrinsicDensity( OldSlotboom NoFermi )
Recombination( SRH(DopingDep) )
Temperature=300
}

* Yield function is calculated using VMODEL of theis example
* Trap definition for the Gate Oxide
Physics (Region=gatox) {
Traps(hNeutral Conc=5e17 EnergyMid=-0.5 FromMidBandGap
eXsection=5.0e-14 hXsection=5.10e-14 eJfactor=0 hJFactor=0)
}

* Trap definition for the Burried Oxide
Physics (Region=box) {
Traps(hNeutral Conc=5e17 EnergyMid=-0.5 FromMidBandGap
eXsection=5.0e-14 hXsection=5.10e-14 eJfactor=0 hJFactor=0)
}

Plot {
ElectrostaticPotential
eTrappedCharge hTrappedCharge
eDensity hDensity
eCurrent/Vector hCurrent/Vector
ElectricField SpaceCharge
SRH RadiationGeneration
}

Math {
Derivatives
RelErrControl
Digits=4
ErRef(electron)=1.e8
ErRef(hole)=1.e8
Notdamped=20
Iterations=25
Newdiscretization
DirectCurrent
ConstRefPot
RhsMin=1e-20
}

* The curve Id(Vg) at Vd=0.1V is traced after 20s of irradiation [1s,21s]
* Vd is decreased to 0.1V [21s,22s] and Vg is ramped [22s,25s]
Electrode {
{ name="gate" Voltage=( 0.0 at 0 , 0 at 22 , 3 at 25.0) }
{ name="substrate" Voltage=0.0 }
{ name="drain" Voltage=( 0 at 0 , @<VD>@ at 0.2 , @<VD>@ at 21, 0.1 at 22, 0.1 at 25) }
{ name="source" Voltage=0.0 }
}


Solve {

Set(Trapfilling=Empty)
Coupled(Iterations=100){ Poisson }
Coupled(Iterations=100){ Poisson Electron Hole}
Unset(Trapfilling)

Transient (
InitialTime=0 FinalTime=25.0
InitialStep=1.0e-1 MaxStep=1 MinStep=1e-4
Increment=1.4 Decrement=2.1
* Saving each 5s(250krad)
Plot { Range=(1 21) Intervals=5 }
)
{ Coupled { Poisson Electron Hole }
CurrentPlot(Time=(Range=(0 25) Intervals=25))
}
Plot(FilePrefix="n@node@")
System("gzip -f n@node@*des.dat")
}

 

[majkl85]

Thanks Chinmoy! I'll consult my code with this, meanwhile I already noticed some errors in material definition of my structure. Just for future generations - It is also necessary to define oxide areas as semiconductor with externally modified parameters to trigger the solution of all equations in those areas.

 

[Avashesh]

Hello, all I am also using gamma radiation model. and I am not getting the desired results. i have a question. can we define donor level or acceptor level trap on the interface of silicon and silicon oxide? because when i am doing this in my simulation an error is occuring i.e. Unable to save dataset 'TrapOccupation_0(Do,Le)': interface 'Silicon/Oxide' not found in grid file MOS_msh.tdr ! hope for any help on this

 

[magaret]

Hello, Avashesh. I am also using gamma radiation model.And I am not getting the desired results.I have the same problem with you, how do you define oxide areas as semiconductor with externally modified parameters to trigger the solution of all equations in those areas？Hope for any help on this.

 

[Avashesh]

Hello Margret, I have successfully done the simulation of my device using gamma radiation model. You have to define the external parameter file for the oxide as semiconductor as per your need. where you have to define parameter of gamma radiation model. for more help you can contact me through email: avasheshniit@gmail.com