CdTe/Si复合衬底Ex-situ退火研究

复合衬底CdTe/ZnTe/Si的晶体质量是导致随后外延的HgCdTe外延膜高位错密度的主要原因之一,因此如何提高复合衬底CdTe/Si晶体质量是确保硅基碲镉汞走上工程化的关键所在。降低复合衬底CdTe/Si位错密度方法一般有:生长超晶格缓冲层、衬底偏向、In-situ退火和Ex-situ退火等,本文主要研究Ex-situ退火对复合衬底CdTe/Si晶体质量的影响。研究表明复合衬底经过Ex-situ退火后位错密度最好值达4.2×105cm-2,双晶半峰宽最好值达60arcsec。

Research of CdTe/Si composite substrate by annealing

One of the main methods to reduce the HgCdTe/Si dislocation density is to reduce CdTe/Si composite substrate′s dislocation density.How to improve the CdTe/Si composite substrate′s crystal quality is very critical for HgCdTe/Si FPAs.The general methods to reduce CdTe/Si composite substrate dislocation density are: growth of superlattice buffer layer,Si substrate misorientention and annealing etc.This paper presents the result of the influence on the quality of CdTe/Si composite substrate by Ex-situ annealing.The research indicates that after Ex-situ annealing,the EPD of composite substrate can reduce to 4.2×105 cm-2,and the FWHM can reduce to 60 arcsec.