How to simulate Si-Based Double Gate MOSFET in Silvaco ATLAS?

Oregon State University

Girish Wadhwa Thank you for sharing. It is indeed an informative playlist for Silvaco TCAD.

If I have any questions I will contact you.

Ali Khakifirooz

Intel

As far as subthreshod slope is concerned, the choice of transport model should not affect your results. The subthreshod slope and in general other metrics of the electrostatic integrity of the device such as DIBL or threshold voltage roll off depend on many things, including your channel thickness, gate dielectric thickness and the details of your junction design. For a ~10nm gate length you'll need a channel thickness of 3-4nm and gate dielectric thickness of 1nm or less and very sharp junctions, like 1nm/dec.

Abdelhalim abdelnaby Zekry

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Amit Das

Jawaharlal Nehru University

Ain Shams University

Nidhal Kamel Taha El-Omari

The World Islamic Science and Education University (WISE)

Ali Zeki

Cyprus International University

Firas Natheer Abdul-Kadir Agha

University of Mosul

Ali Khakifirooz

Intel

Please be specific on why you think the results are not correct. It also helps if you start with the simplest physics models such as drift diffusion transport and then add more complex models.

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Oregon State University

I was trying to simulate MOSFET of 10 nm gate length. I have found on some previously published paper that the subthreshold slope of this gate length MOSFETs is around 85 mV/decade.

But I got SS around 290 mV/decade. That's why I am assuming my results are not correct.

And I will try with drift diffusion model. Thanks for the Suggestion.

1 Recommendation

Intel

3 Recommendations

Oregon State University

Dear Ali Khakifirooz,

Thank You for your valuable comment. It will help me a lot in my work.

Shruti Mehrotra

GlobalFoundries Inc.

Hello,

I'm simulating a short channel double-gate MOSFET using Silvaco ATLAS employing NEGF transport. But my off current is too high. Can u please tell me what scattering models should be used with it?

Best wishes,

Shruti.

Oregon State University

Hello Ms. Shruti,

For Double gate MOSFET I have solved SCHRODINGER equation in Non Equilibrium Green's Function (NEGF) approach in the mode (subband) space.

I have considered fully depleted ballistic (no scattering) nMOSFETs. That's why no scattering model haven't been specified.

You can check Quantum x 12 Example for simulating DG MOSFET using NEGF transport.

Oregon State University

Girish Wadhwa Thank you for sharing. It is indeed an informative playlist for Silvaco TCAD.

If I have any questions I will contact you.

Simulation of cmos inverter using silvaco tcad

Discussion

2 replies

Asked 28th Sep, 2023

Anusuya Periyasami

i am trying to simulate cmos inverter using silvaco tcad but i am not getting. can anyone provide sample code for this?

Can anyone provide a SILVACO TCAD simulation code(in DeckBuild environment) for JLFET?

Junctionless FET code is needed for reference purpose

3 answers

Asked 3rd Jul, 2022

Shivendra Singh

How to export the data in a .str file in silvaco?

I am trying to show the variation of various parameters along the length of a device in silvaco. I am able to generate a tonyplot from the .str file but am not able to export the data. I need to plot the numbers on a log-log scale and also do some fitting (trying to make the plots in excel or origin). In the general .log files that are generated, I am able to export, but that does not work for .str files.

8 answers

Asked 8th Feb, 2020

Harsh Chittora

How i should resolve the following warning in the Silvaco simulation?

I want to extract the Id-Vds curve to calculate the breakdown voltage (BV) of a HEMT. For this purpose, the Vds has swept from 0 to 100 (or even less than 100) but it is failed. The warnings are "Iteration limit for Newton algorithm exceeded."

2 answers

Asked 3rd Oct, 2016

Mitra Salami

What causes the error" tried to use non existing contact "gate" " in Sentaurus TCAD?

I am trying to simulate a double gate mosfet in 2D. Both top and bottom gates are named "gate" in the structure file and also the sdevice file.

2 answers

Asked 1st Aug, 2023

Muhammad Shaffatul Islam

Your help will be appreciated.

Thanks

Anything wrong with my double gate MOSFET design?

I manage to manipulate bias voltage (VDS) to verify the performance of my double gate MOSFET device, that is to observe the trend of the transfer characteristic. Having myself perplexed, the current does not increase in order based on the increasing VDS (from 0.1 to 1.0V). Theoretically, the higher the bias voltage, the steeper the current should be. But, it does not happen to be that way in this case, why?

Be the first to answer

Asked 22nd Jul, 2023

Yu Chai Sek

What causes this warning in Silvaco TCAD?

Thank you for answering my question, dear Sir/Madam:

3 answers

Asked 2nd Mar, 2022

Wang Rick

I tried to simulate an FTJ structure with ATLAS in Silvaco TCAD, and this warning occured:

Warning: Internal error in linear solver.

This situation rarely occurs in normal circumstances.

This error could indicate a ill-defined problem.

Check structure and models for possible conflicts.

Warning: Cannot trap. Cannot reduce bias

step. Choose smaller bias step size, or

check structure and or models.

below is my source code, and I wonder what's wrong with it:

go atlas

mesh outf=meshferro.str

x.m loc=0.0 spacing=0.001

x.m loc=0.1 spac=0.001

y.m loc=-0.3 spacing=0.01

y.m loc=0.0 spacing=0.01

y.m loc=-0.1 spacing=0.001

y.m loc=-0.108 spacing=0.001

y.m loc=0.5 spac=0.01

region num=1 silicon y.min=0.0

region num=2 material=tin y.max=0.0 y.min=-0.1

region num=3 material=hfo2 y.max=-0.1 y.min=-0.104

region num=4 material=zro2 y.max=-0.104 y.min=-0.108

region num=9 material=al2o3 y.max=-0.108 y.min=-0.110

region num=10 material=al y.max=-0.110 y.min=-0.3

electrode top name=gate

electrode bottom name=sub

doping region=1 conc=1e15 uniform p.type

save outf=ftj04.str

tonyplot ftj04.str

models region=3 ferro

material region=3 ferro.ec=20e3 ferro.pr=0.5e-6 ferro.ps=1.0e-6 ferro.epsf=200

method newton trap

solve vgate=-5

probe x=0 y=-0.3 dir=90 polarization

log outf=ferro04.log master

solve name=gate vfinal=5 vstep=0.05 ac freq=1e-6 direct

material region=3 ferro.ec=-20e3

solve name=gate vfinal=-5 vstep=-0.05 ac freq=1e-6 direct

tonyplot ferro04.log -set ferroex01_0.set

Can you help me with this error related to silvaco TCAD?