摘要
主要分析了不同溴甲醇溶液腐蚀方法对分子束外延用碲锌镉(211)B衬底表面粗糙度及反射式高能电子衍射(RHEED)图样的影响。实验发现化学抛光后未使用溴甲醇腐蚀的CZT(211)B衬底虽然表面粗糙度较小(小于1.0 nm),但表面RHEED衍射图样无任何衍射点或者条纹;采用0.05%溴体积比的溴甲醇溶液腐蚀CZT(211)B衬底时,即使腐蚀极短的时间,衬底表面粗糙度也达到2.0 nm以上,且表面存在高密度的柱状物,衬底表面RHEED图样呈圆点状或条纹较粗且存在亮点;采用0.01%溴体积比的溴甲醇溶液腐蚀CZT(211)B衬底,表面粗糙度可控制在1.0 nm左右,同时RHEED图样为特征的CZT(211)B晶面短条纹衍射图样,条纹清晰,同时多片衬底重复实验结果一致。同时在其上分子束外延的未优化的中波碲镉汞材料半峰宽为(49.1±5.9)arcsec,组分为0.3083±0.0003,厚度为6.54±0.019μm。
The influence of different bromomethanol solution etching methods on the surface roughness and Reflection High-Energy Electron Diffraction(RHEED)pattern of CZT(211)B substrate for molecular beam epitaxy were analyzed in this paper.It was found that CZT(211)B substrate which had not been etched with bromomethanol after chemical polishing had a small surface roughness(less than 1.0 nm),but the RHEED pattern had no diffraction spots or stripes.When the CZT(211)B substrate is etched by a 0.05%vol.%bromomethanol solution,even if the etching is extremely short time,the surface roughness of the substrate reaches 2.0 nm or more,and a high-density pillar is present on the surface,and the RHEED patterns are round or thick stripe with bright spots.When the CZT(211)B substrate is etched by a 0.01 vol%bromomethanol solution,The surface roughness can be controlled at about 1.0 nm,and the RHEED pattern is clear short stripes which is the standard diffraction pattern of CZT(211)B crystal face.At the same time,the results of repeated experiments on multiple substrates are consistent.The unoptimized medium-wave HgCdTe material by the MBE on these substrates has a Full Width at Half Maximum(FWHM)of(49.1±5.9)arcsec,a composition of 0.3083±0.0003,and a thickness of(6.54±0.019)μm.
作者
吴亮亮
王丛
高达
王经纬
刘铭
周立庆
WU Liang-liang;WANG Cong;GAO Da;WANG Jing-wei;LIU Ming;ZHOU Li-qing(North China Research Institute of Electro-Optics,Beijing 100015,China)
出处
《激光与红外》
CAS
CSCD
北大核心
2019年第5期571-576,共6页
Laser & Infrared
