Introduction
DEVSIM is semiconductor device simulation software which uses the finite volume method. It solves partial differential equations on a mesh. The Python interface allows users to specify their own equations.
Software Features
Python and Tcl scripting
DC, small-signal AC, impedance field method, transient
User specified partial differential equations (PDE).
1D, 2D, and 3D simulation
1D, 2D mesher
Import 3D meshes.
2D cylindrical coordinate simulation
ASCII file format with PDE embedded.
Please see INSTALL file for installation instructions from source. Please see NOTICE and LICENSE files for copyright and license information.
Supported Platforms
macOS 10.13 Intel (x86_64)
macOS 12 M1 (arm64)
Microsoft Windows
Red Hat 7 (Centos Compatible)
License
The source code and accompanying examples are provided by Devsim LLC. It is licensed under the Apache 2.0 License. A brief synopsis of this license is available here. Other files are subject to the license terms of their copyright owners.
DEVSIM is a registered trademark of DEVSIM LLC.
Install
The recommended installation method is to use pip to download from https://pypi.org/project/devsim/. Please see the installation notes in the Documentation with the most update information in the INSTALL.md file in the installation or online here https://github.com/devsim/devsim/blob/main/INSTALL.md.
Download
Binaries
Archived citable releases are stored here. The recommended installation method is in Install.
Source Code
Examples
In addition to the examples provided with the distribution, and listed in the documentation. The following examples are also available:
Bipolar Junction Transistor Simulation
Density Gradient Simulation
MOSCAP simulation with quantum correction for carrier density at semiconductor-insulator interfaces
3D MOSFET Example
Simulation scripts used to create 3D MOSFET example used in: J. E. Sanchez and Q. Chen, “Element Edge Based Discretization for TCAD Device Simulation,” in IEEE Transactions on Electron Devices, doi: 10.1109/TED.2021.3094776.
Documentation
Manual
PDF Version
Online HTML Version
Publications
Project
DEVSIM: A TCAD Semiconductor Device Simulator
Sanchez, J. E., “DEVSIM: A TCAD Semiconductor Device Simulator,” Journal of Open Source Software, 2022, doi: 10.21105/joss.03898.
Element Edge Based Discretization for TCAD Device Simulation
J. E. Sanchez, and Q. Chen, “Element Edge Based Discretization for TCAD Device Simulation,” IEEE Transactions on Electron Devices, 2021, doi: 10.1109/TED.2021.3094776.
Preprint available from TechRxiv, doi: 10.36227/techrxiv.14129081.
Using the Simulator
Analytical model for donor like Gaussian traps in organic thin-film transistor
Q. Chen, J. E. Sanchez, D. Lin, Y. Lei, G. Zhu, “Analytical model for donor like Gaussian traps in organic thin-film transistor,” Organic Electronics, 2022 doi: 10.1016/j.orgel.2022.106464.
QS-Devsim
Technology computer aided design based deep level transient spectra: Simulation of high-purity germanium crystals
J. Lauwaert, “Technology computer aided design based deep level transient spectra: Simulation of high-purity germanium crystals,” Journal of Physics D: Applied Physics, 2021, doi: 10.1088/1361-6463/ac34ad.
The Impact of Contact Position on the Retention Performance in Thin-Film Ferroelectric Transistors
Q. Chen, D. Lin, Q. Wang, J. Yang, J. E. Sanchez, and G. Zhu, “The Impact of Contact Position on the Retention Performance in Thin-Film Ferroelectric Transistors,” Physica Status Solidi A 2100408, 2021, doi: 10.1002/pssa.202100408.
Designing a Simulator for an Electrically-Pumped Organic Laser Diode
L. Hulbert, “Designing a Simulator for an Electrically-Pumped Organic Laser Diode,” Master’s Thesis, California Polytechnic State University, San Luis Obispo, CA, 2019, doi: 10.15368/theses.2019.60.
White Papers
Semiconductor Device Simulation Using DEVSIM
https://devsim.com/semiconductor-device-simulation-using-devsim/
Symbolic Model Evaluation for TCAD Device Simulation
TCAD Sensitivity Analysis for Device Optimization
Presentations
Semiconductor Device Simulation Using DEVSIM
https://devsim.com/devsim-simulation-example-slides/
This is a recent slide presentation showing simulation examples using DEVSIM.
Resources
DEVSIM
Online Forum
Bug Reporting
Blog
This blog contains information about DEVSIM and general TCAD topics.
Source code statistics
TCAD Resources
TCAD Central
TCAD information resource
Model Example
Solving the Poisson equation in a dielectric is:
\(\epsilon \int \nabla \psi \cdot \partial r = 0\)
which is equivalent to solving
\(\epsilon \int \vec{E} \cdot \partial \vec{s} = 0\)
In DEVSIM, the surface integral is performed by specifying an equation in the region with an edge model which is the negative gradient of the potential, \(\psi\). An example implementation is located in 1
def CreateOxidePotentialOnly(device, region, update_type="default"):
'''
Create electric field model in oxide
Creates Potential solution variable if not available
'''
if not InNodeModelList(device, region, "Potential"):
print "Creating Node Solution Potential"
CreateSolution(device, region, "Potential")
efield="(Potential@n0 - Potential@n1)*EdgeInverseLength"
# this needs to remove derivatives w.r.t. independents
CreateEdgeModel(device, region, "ElectricField", efield)
CreateEdgeModelDerivatives(device, region, "ElectricField", efield, "Potential")
dfield="Permittivity*ElectricField"
CreateEdgeModel(device, region, "PotentialEdgeFlux", dfield)
CreateEdgeModelDerivatives(device, region, "PotentialEdgeFlux", dfield, "Potential")
equation(device=device, region=region, name="PotentialEquation", variable_name="Potential",
edge_model="PotentialEdgeFlux", variable_update=update_type)