Synopsys, Inc.
Method to approximate chemical potential in a ternary or quaternary semiconductor

Abstract:

Roughly described, a method is provided to approximate chemical potentials of elements in ternary and quaternary compound semiconductors, for example III-V semiconductors. In embodiments of the present invention, three, four, or more relationships are solved together to find approximated chemical potentials for each group III element and each group V element. The first relationship relates total energy of a defect-free system to the sum, over all of the group III and group V elements, of (a) provisional chemical potential for the respective element, times (b) number of atoms of the respective element within a supercell. The second relationship describes a stoichiometric balance relationship between total atomic density of all group III atoms and total atomic density of all group V atoms. The other relationship or relationships balance mole fraction ratio between group III atoms, or between group V atoms.