Growth of H1-x(Cd1-yZny)(x)Te epilayers on (100) Cd1-yZnyTe/GaAs substrates by ISOVPE

Hg1-xCdxTe (MCT) and Hg1-x(Cd1-yZny)(x)Te (MCZT) epilayers were grown by is othermal vapor phase epitaxy (ISOVPE) using CdTe and lattice matched Cd1-yZ nyTe (y approximate to 0.045, CZT) layers, respectively, of various thickne ss on (100) GaAs as substrate. The problems of void formation and Ga outdif fusion can be overcome by using a sufficiently thick substrate layer. The I SOVPE epilayers show improved quality compared with substrate and their qua lity was found to be independent of substrate. It was found that FWHM value s for MCZT epilayers grown on lattice matched CZT/GaAs were 70-90 arcsec, s maller than those reported here for MCT/CdTe/GaAs. Despite the broader FWHM for CZT/GaAs, a significant improvement in the quality of ISOVPE MCZT epil ayers grown on these substrates was observed. This result is mainly attribu ted to the smaller lattice mismatch and the effect of Zn addition compared with MCT/CdTe. (C) 1999 Elsevier Science S.A. All rights reserved.