Effects of substrate and compositional disorder upon optical and lattice vibration properties of quaternary semiconductor GaxIn1−xAsyP1−y

The present paper deals with a theoretical study of optical and phonon properties of quaternary semiconductor GaxIn1−xAsyP1−y alloys lattice matched to InP, GaAs and ZnSe in the zinc-blende phase. The calculations are primarily based on the pseudopotential formalism under the virtual crystal approximation (VCA) that incorporates the disorder effect. Special attention has been devoted to the effects of compositional disorder and substrate upon the features of interest. The numerically calculated values show reasonable agreement with the experiment. It is found that the compositional disorder has an important effect on the studied properties and should be included in the calculations. The substrate effect is also found to change the properties of interest suggesting thus that more diverse opportunities regarding optical and lattice vibration properties may be provided by a proper choice of the substrate and the composition y.