Band Structure of Si computed with harrison.py and chadicohen.py programs:
Click here for the harrison.py program, which computes the band structure of semiconductors.
I've also written a slight modification of this program, called "chadicohen.py", which can be obtained here. This program is the tight binding program that Chadi and Cohen outline in their 1975 paper.
Click here for instructions on how to run either of these programs under Windows95, 98, or NT.
The following is from the notes in the programs.
-c # The atomic number for the semiconductor cation (default=14) -a # The atomic number for the semiconductor anion (default=14) -n # The number of points in each Brillouin zone region (default=10) -h Print this help screen and exit -P Output a postscript image of the band structure -G Output a GIF of the band structure
-s xx The Structure to compute; currently supported are: C Diamond Si Silicon Ge Germanium GaAs Gallium Arseninde ZnSe Zinc Selenide -n # The number of points in each Brillouin zone region (default=10) -h Print this help screen and exit -P Output a postscript image of the band structure -G Output a GIF of the band structure
Here are some sample band gaps (in eV, from Kittel) that may aid in fitting:
C indirect 5.4 Si indirect 1.17 Ge indirect 0.744 Sn direct 0.00 GaAs direct 1.52 GaP indirect 2.32 GaN ?? 3.5 (not from Kittel) InP direct 1.42 InAs direct 0.43
Copyright 1999, Richard P. Muller and William A. Goddard, III
This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.