红外与毫米波学报, 2017, 36 (5): 589, 网络出版: 2017-11-21
磁光—光致发光分析CdZnTe单晶带边浅杂质能级
Shallow impurity levels in CdZnTe probed by magneto-photoluminescence
摘要
通过对Bridgeman方法生长的CdZnTe单晶样品进行光致发光(Photoluminescence, PL)光谱测量, 发现CdZnTe样品表面Te沉淀物的存在明显影响能量低于1.5 eV的深能级发光过程.进一步对CdZnTe晶锭的不同位置取样进行低温变磁场光致发光光谱测试, 获得高分辨光谱信息.拟合分析结果表明: (1)在不含Te沉淀物的CdZnTe样品内部存在应力分布, 并因此导致轻、重空穴带分裂;(2)1.57 eV发光特征源于浅施主杂质与价带间的复合过程.
Abstract
This paper reports photoluminescence (PL) and magneto-PL study of CdZnTe single crystal grown by Bridgman method. Magneto-PL measurements on two CdZnTe samples in the sample crystal were realized at low temperature with sufficiently high spectral resolution and signal-to-noise ratio. PL spectra reveal that the Te inclusions near the CdZnTe surface affects obviously the PL processes energetically below 1.5 eV. Further analysis with curve-fitting process shows that (1) stress distribution exists inside the CdZnTe sample without Te inclusions, and the stress causes the splitting of the heavy-and light-hole subband. (2) The 1.57-eV PL feature originates from the shallow-donor to valence-band recombination.
祁镇, 盛锋锋, 朱亮, 杨建荣, 陈熙仁, 邵军. 磁光—光致发光分析CdZnTe单晶带边浅杂质能级[J]. 红外与毫米波学报, 2017, 36(5): 589. QI Zhen, SHENG Feng-Feng, ZHU Liang, YANG Jian-Rong, CHEN Xi-Ren, SHAO Jun. Shallow impurity levels in CdZnTe probed by magneto-photoluminescence[J]. Journal of Infrared and Millimeter Waves, 2017, 36(5): 589.