用拉曼散射分析碲镉汞中的缺陷

本文分析了碲镉汞（HgCdTe或MCT）中Te沉淀相，Hg空位的拉曼散射峰，以及碲镉汞表面完整性与它的二级拉曼散射峰的关系，MCT中的Te沉淀相的拉曼峰位于125和145cm^-1处，此峰与标准的Te三角晶系的拉曼峰相比，往高能方向移动了2cm^-1，这表明Te沉淀相受到了压应力的作用，MCT中位于108cm^-1处微弱的拉曼峰来源于Hg空位，此峰只在p型和包含有反型层的MCT中出现，在n型的MCT中几乎不出现，MCT的拉曼二极散射峰对其表面完整性非常敏感，表面完整性好的拉曼峰很明显，而表面完整性较差的峰则不太明显，此峰的1LO（T）模的强度测量对晶体制备过程中的表面分析也可能供有用的信息。

Defect Analysis in Mercury Cadmium Telluride by Raman Scattering

Telluride precipitates in HgCdTe(MCT) and Raman scattering peaks of Hg vacancies are reported.We also analyze the relationship between the crystal surface perfection of MCT and its second order scattering peaks.Intense bands at 125 and 145 cm -1 confirm them to be precipitates,and there is 2 cm -1 shift to high frequency in comparison with intense bands of normal trigonal Te.This shows the compressive stress exists around Te precipitates.The weak Raman peak at 108 cm -1 arise from Hg vacancies.This peak is only found in p type MCT and MCT including p n junction,and is not found in n type MCT.The intensity of the second order scattering peaks in MCT is very sensitive to its crystal surface perfect.To good surface perfect,these peaks are very distinct,and to poor surface perfect,they are not distinct.The intensity measurement of 2LO(T) mode in the second order scattering peaks can provide useful information for surface analysis in crystal preparation process.