Semiconductor alloy theory: Internal strain energy and bulk modulus.

Abstract

A theory is developed for the internal strain energy (ISE) and bulk modulus in semiconductor alloys. The ISE is shown to be governed by the square fluctuation of the bond lengths and an effective force constant which couples the atomic clusters to the environment. Analytical models show that the bulk moduli and bond lengths as functions of concentration of these alloys bow only slightly below the straight-line average. This work provides a basis of an effective-medium theory for calculating the input cluster energies in a statistical theory.