STUDY OF STRUCTURAL-PROPERTIES OF MOVPE GROWN ZNMGSSE LAYER BY HRXRD AND CATHODOLUMINESCENCE

The effect of layer thickness on the structural and electro-optical pr operties of MOVPE grown lattice matched Zn1-yMgySxSe1-x/GaAs layers we re examined by high resolution X-ray diffractometry (HRXRD) and cathod oluminescence (CL) combined with secondary electron (SE) imaging. Our X-ray results show that the lattice parameter and the strain status de pend on the layer thickness, although the quaternary layers were grown with nominally the same growth parameter. All samples have a high dis location density observed by panchromatic CL image (p>10(5) cm(-2)). F urthermore, inhomogeneous emission intensity on CL micrographs and wav y surfaces on SE images were also observed for all samples. With incre asing layer thickness the contrast of intensity inhomogeneities in CL becomes stronger, while a significant lattice parameter variation is o bserved. (C) 1998 Published by Elsevier Science S.A.