Molecular-beam epitaxial growth of CdZnTe/ZnTe QW structures and superlattices on GaAs (100) substrates for optoelectronics

Abstract

The effect of the 5 nm thick ZnTe intermediate layers obtained by solid crystallization at growth temperature on the optical properties of ZnTe epilayers grown by molecular beam epitaxy (MBE) on (100) GaAs substrates has been investigated by low temperature photoluminescence and reflectance spectroscopy. Reduction of nonradiative center concentration and improvement of ZnTe epilayer photoluminescence characteristics have been achieved using of solid phase crystallized intermediate layers. At the same time defect depth nonuniformity was found to occur in ZnTe epilayers with and without such intermediate layers. Use of such surfactant layer and optimized technology conditions on early stage of growth makes possible to obtain CdZnTe/ZnTe quantum wells and super lattices with high luminescence efficiency for further application.