INFLUENCE OF GROWTH-PARAMETERS ON THE PROPERTIES OF ZNSE-GAAS(001) HETEROSTRUCTURES

ZnSe-GaAs(001) heterostructures were fabricated by molecular beam epitaxy at 290 degrees C employing different Zn/Se flux ratios. Se-rich growth conditions resulted in a Se-rich interface composition and lower valence band offsets (as low as 0.6 eV). Zn-rich conditions yielded a Zn-rich interface composition, and higher valence band offsets (as high as 1.2 eV). Improved optical properties of the ZnSe overlayers were achieved by employing non-stoichiometric growth conditions only in the early stages of growth (similar to 2 nm).