Strain-Induced Shift of Optical Phonon Frequency in InGaP Layers Grown on GaAs Substrates

Abstract
Raman spectra from InGaP epitaxial layers grown on GaAs (001) and (111)B substrates were studied. Both LO and TO phonon frequencies varied, not only with the alloy composition, but also with the lattice strain induced by the lattice mismatch between the epitaxial layer and the substrate. The amounts of these frequency variations agreed with the calculations, including a two-dimensional elastic strain in the epitaxial layer.