Vapor phase epitaxy of Hg1−xCdxTe on CdTe heteroepitaxial substrates

Abstract To grow Hg 1− x Cd x Te layers for infrared (IR) detector fabrication, the new technique of vapor phase epitaxy (VPE) on CdTe heteroepitaxial substrates (HS) has been studied in detail. A theoretical simulation of the VPE growth process has been carried out. Hg 1− x Cd x Te layers were grown by VPE at 530°C in evacuated ampoules. CdTe sapphire and CdTe GaAs HS obtained by metalorganic chemical vapor deposition (MOCVD) technique were employed as substrates. The melt solution of Hg 1− y Te y was used as a VPE source, and the dependence of the VPE growth rate on the source composition in the range y = 0.65−0.85 was studied. Various experimental methods were used to characterize the effect of VPE growth conditions on the properties of Hg 1− x Cd x Te layers like component distribution, surface morphology, structural quality, optical and electrical properties. Our results show a great potential for the VPE on HS technique for the epitaxy of IR grade Hg 1− x Cd x Te.