EFFECT OF CDTE LAYER THICKNESS ON HG1-XCDXTE EPILAYER GROWTH BY ISOTHERMAL VAPOR-PHASE EPITAXY USING (100)CDTE GAAS SUBSTRATES AND VOID FORMATION AT THE INTERFACE/

The growth of Hg1-xCdxTe (MCT) epilayers by isothermal vapor phase epi taxy (ISOVPE) on (100) CdTe/GaAs substrates, with various thicknesses of CdTe layers, is reported. Subsequent to ISOVPE growth of MCT layer, we observed the formation of triangular voids at the interface betwee n CdTe and GaAs, which strongly depends on the thickness of the CdTe s ubstrate layers. The problem of void formation and Ga outdiffusion cal l be overcome by using a sufficiently thick CdTe layer. Although the c rystallinity of CdTe layers grown on GaAs by hot wall epitaxy (HWE) is strongly related to thickness, the quality of MCT epilayers is better than that of the substrate layer and is independent of the quality of CdTe layers. This result is attributed to the growth mechanism of ISO VPE being different from other epitaxial methods.