Growth of ZnSe films on GaAs(100) substrate by x-ray-enhanced, vapor-phase epitaxy

Epitaxial films of ZnSe deposited on a GaAs(100) substrate are grown by x-ray-enhanced, vaporphase epitaxy (XEVPE) using a URS-55a source (CuKα emission, λ=1.542 Å, P∼1–3 mW/cm2) from powdered raw material in a purified hydrogen flow. The differences in the photoluminescence and exciton reflection spectra are investigated for single-crystal ZnSe films on GaAs(100) at T=4.5 K, which are subjected to compressive strain and are grown by x-ray enhanced and conventional VPE. The results indicate an improvement of the crystallographic structure of the epitaxial layer prepared by XEVPE. This is further corroborated by data from x-ray diffraction analysis. The observed phenomena are attributed to x-ray activated adsorption and desorption processes and to a change in the surface mobility of adsorbed atoms.