MIGRATION-ENHANCED EPITAXY GROWTH AND CHARACTERIZATION OF HIGH-QUALITY ZNSE/GAAS SUPERLATTICES

We report the growth of high quality ZnSe/GaAs superlattices by migration-enhanced epitaxy (MEE) and their characterization using x-ray diffraction, electron microscopy, and photoluminescence. A streaky reflection high-energy electron diffraction (RHEED) pattern and strong, persistent RHEED oscillation during the MEE growth of the superlattices indicate a smooth growing surface. The sharp satellite peaks observed clearly in the double-crystal x-ray diffraction rocking curve of a 21-period ZnSe/GaAssuperlattice confirm the excellent crystalline and interfacial quality of the superlattice. Cross-section high-resolution electron microscopy indicates coherent lattice arrangement and abrupt interface at ZnSe-on-GaAs as well as GaAs-on-ZnSe heterointerfaces. Photoluminescence spectra from a superlattice with a periodicity of 40 nm show a strong peak at a wavelength of 829.5 nm with a linewidth of 6.3 meV at a temperature of 10 K; we believe this to be the first observation of photoluminescence from any multilayer structure involving GaAs-on-ZnSe growth.