Correlation between electrical and structural properties ofchlorine doped ZnSe epilayers grown by molecular beam epitaxy

Abstract

ZnSe epilayers have been studied by Van der Pauw measurements, C-V profiling, SIMS, TEM and X-raydiffraction in order to correlate electrical and structural properties. At least up to 10 19 cm -3, SIMS and electricaldata are in good agreement, indicating a high efficiency of the chlorine incorporation at optimum growth conditions.Homogeneously and planar doped epilayers have been grown either directly on the (100) GaAs substrate or on anundoped, relaxed ZnSe buffer layer. For a given SIMS concentration of chlorine atoms, the free carrier concentrationcan be enhanced up to one order of magnitude for planar doped samples. The influence of a relaxed bufferlayer on dopant activation and depth profile is discussed and correlated to dislocation distribution determined byTEM.