Si/CdTe复合衬底HgCdTe液相外延材料的生长与性能分析

通过改进推舟液相外延技术,成功地在(211)晶向Si/CdTe复合衬底上进行了HgCdTe液相外延生长,获得了表面光亮的HgCdTe外延薄膜.测试结果表明,(211)Si/CdTe复合衬底液相外延HgCdTe材料组分及厚度的均匀性与常规(111)CdZnTe衬底HgCdTe外延材料相当;位错腐蚀坑平均密度为(5～8)×105 cm-2,比相同衬底上分子束外延材料的平均位错密度要低一个数量级;晶体的双晶半峰宽达到70″左右.研究结果表明,在发展需要低位错密度的大面积长波HgCdTe外延材料制备技术方面,Si/CdTe复合衬底HgCdTe液相外延技术可发挥重要的作用.

LPE Growth and Characterization of HgCdTe on Si Based Substrate

HgCdTe epilayer grown on(211)Si/CdTe compound substrate was first obtained by a novel liquid-phase epitaxy technique.The etch pit density of the layer is about (5~8)e5cm-2,which is lower than that grown by MBE.The FWHM of the X-ray rocking curve of the epilayer can be better than 70" .The control level of composition and thickness of the epilayer is the same as that of the HgCdTe routine LPE technique on (111) CdZnTe substrate.But the density of surface defects on (211) HgCdTe layer is higher than that of epilayer grown on (111) CdZnTe substrate at present.The result indicates that (211) Si-based HgCdTe LPE can play an important role in growing low etch pit density Si-based HgCdTe materials used for the fabrication of longwave infrared focal plane arrays.