SURFACE RECONSTRUCTION AND STABILIZATION IN MOMBE OF ZNSE REVEALED BY INSITU RHEED MONITORING

Growth processes in MOMBE of ZnSe were characterized by in-situ RHEED monitoring. Se pretreatment of the substrate surface prior to the growth results in (2×1) reconstruction, which may originate from the GaSe bonds. After the growth starts, the VI/II ratio and the growth temperature must be low so that ridges are not formed initially. These pretreatments and growth conditions successfully avoid the interdiffusion of constituent elements at the ZnSe/GaAs heterointerface. During the epitaxial growth, Zn- and Se-stabilized surfaces take c(2×2) and (2×1) reconstruction patterns, respectively. Alternate irradiation of DMZn and DMSe results in an alternate change in the RHEED patterns, and layer-by-layer growth can be achieved by controlling the supply sequence according to the RHEED patterns. © 1989.