Raman study of disorder and strain in epitaxial ZnSxSe1−x films on a GaAs substrate

Quantitative characterization of disorder and strain in ZnSxSe1−x/GaAs lattice-mismatched semiconductor heterostructures was successfully done by means of Raman spectroscopy. The alloy disorder and the phonon coherence length in epitaxial ZnSxSe1−x films were estimated from the Raman linewidth of the ZnSe-like LO phonon by using a spatial correlation model. The strain due to the lattice mismatch near the interface between ZnSxSe1−x and GaAs was deduced from the linewidth of the GaAs LO phonon