Influences of Te-Rich and Cd-Rich Precipitates of CdZnTe Substrates on the Surface Defects of HgCdTe Liquid-Phase Epitaxy Materials

Abstract

Influences of Te-rich and Cd-rich precipitates of CdZnTe substrates on the surface defects of HgCdTe epilayers grown by Te-rich liquid-phase epitaxy were investigated. The results show that HgCdTe surface defects are mainly attributable to precipitates on CdZnTe substrate surfaces. At the same time, the remelting of substrate surface layers during the liquid-phase epitaxial process also affects the number and morphology of HgCdTe surface defects. According to the morphological characteristics of surface defects, three types of surface defects were observed on the surfaces of HgCdTe epilayers. There are no obvious differences in the morphologies of the surface defects grown on Te-rich and Cd-rich substrates. However, the dislocation distributions around surface defects are different for HgCdTe epilayers grown on different substrates.