静压下ZnS∶Te中Te等电子陷阱的发光  

PHOTOLUMINESCENCE OF Te ISOELECTRONIC CENTERS IN ZnS:Te UNDER HYDROSTATIC PRESSURE

作　　者：方再利[1] 苏付海[1] 马宝珊[1] 丁琨[1] 韩和相[1] 李国华[1] 苏萌强[2] 葛惟锟[2] 

机构地区：[1]中国科学院半导体研究所半导体超晶格与微结构国家重点实验室,北京100083 [2]香港科技大学物理系

出　　处：《红外与毫米波学报》2004年第1期38-42,共5页Journal of Infrared and Millimeter Waves

基　　金：国家自然科学基金资助项目 ( 60 1760 0 8)

摘　　要：研究了 4块ZnS∶Te薄膜样品 (Te组分从 0 .5 %到 3.1% )的光致发光谱在常压下的温度特性 .对于Te组分较小的 2块样品观察到 2个发光峰 ,分别来自Te1和Te2 等电子陷阱 ;而对Te组分较大的 2块样品则只观察到 1个来自Te2 等电子陷阱的发光 .我们还研究了这些发光峰在低温 15K下的流体静压压力行为 .观察到与Te1有关的发光峰压力系数比ZnS带边的要大很多 ,而与Te2 有关的发光峰压力系数则比带边小 .根据Koster Slater模型 ,价带态密度半宽随压力的增加是Te1中心有较大压力系数的主要原因 ,而Te1和Te2The photoluminescence of four epitaxial ZnS: Te samples with Te concentration from 0.5% to 3.1% was investigated at different temperature and ambient pressure. Two well-known emission bands related to the isolated Te-1 and Te-2 pair isoelectronic centers were observed for the samples with Te concentrations of 0.5% and 0.65%. For the samples with Te concentrations of 1.4% and 3.1%, only was the Te-2-related peak observed. The pressure behaviors of these emission bands, were studied at 15 K. The Te-1 -related band has faster pressure shift to higher energy than ZnS band gap. On the other hand, the pressure coefficient of Te-2 -related bands is smaller than that of the ZnS band gap. According to a Koster-Slater model, we found that the increase of the density bandwidth of the valence band with pressure is the main reason for the faster shift of the Te-1 centers, while the relatively large difference in the pressure behavior of the Te-1 and Te-2 centers is mainly due to the difference in the pressure-induced enhancement of the impurity potential on Te-1 and Te-2 centers.

关 键 词：光致发光 硫化锌 碲掺杂 碲等电子陷阱 压力系数 半导体材料 

分 类 号：O472.3[理学—半导体物理]