Epitaxial ZnS, ZnSe and ZnS-ZnSe Superlattices Grown on (001)GaAs By Pulsed-Laser Ablation

Abstract

ABSTRACTPulsed KrF (248nm) laser ablation of polycrystalline ZnS and ZnSe targets has been used to grow high quality, fully epitaxial ZnS and ZnSe thin films on (001) GaAs. Photoluminescence measurements of the ZnS thin films show strong edge emission, while ZnSe thin films show free excitonic as well as donor and acceptor peaks. By alternately ablating each target, strained layer superlattices of the form (ZnSe)m–(ZnS)n were grown with as many as 65 periods of compositional modulation. A ZnSxSe1–x structure also was fabricated which simultaneously incorporated both continuously graded and abrupt compositional changes.