GROWTH AND CHARACTERIZATION OF ZNSE GAAS SINGLE-QUANTUM-WELL STRUCTURES/

The integration of II-VI and III-V semiconductors into a single II-VI/ III-V heterojunction device enables the exploitation of the many simil arities, as well as the many differences, in material properties (ener gy bandgap, lattice constant, dielectric constant, etc.) to create new devices exhibiting unique optical and electronic properties. The epit axial growth of dielectric quantum wells (QWs) composed of ZnSe and Ga As is under investigation. One of the critical factors affecting the p roperties of the ZnSe/GaAs QW structure is the formation of the hetero valent interfaces, particularly the formation of the inverted interfac e formed by GaAs nucleated onto a ZnSe epitaxial surface, The stoichio metry of each interface is engineered by using various growth techniqu es, Due to the severe mismatch in optimal growth temperatures for the two material systems (600 degrees C for GaAs and 300 degrees C for ZnS e), additional emphasis has been placed on the reduced temperature gro wth of GaAs on ZnSe. The effects of the growth parameters and nucleati on methodology are examined by in situ surface reconstruction analysis using reflection high energy electron diffraction and ex situ using t ransmission electron microscopy. The optical properties of the reduced temperature GaAs and ZnSe/GaAs QWs are further investigated with phot oluminescence.