摘要
采用基于密度泛函理论的第一性原理方法,对正交碘化铟(InI)晶体可能存在的6种本征点缺陷(碘空位、铟空位、碘占铟位、铟占碘位、碘间隙、铟间隙)结构进行优化.通过缺陷形成能的计算,得出各缺陷在生长过程中形成的难易程度;通过态密度的计算,分析出各种缺陷能级位置及其对载流子传输的影响.结果表明:最主要的低能缺陷铟间隙会引入复合中心和深空穴陷阱,前者降低少数载流子的寿命,后者俘获价带的空穴而降低空穴的迁移率-寿命积.计算结果为实验中提高InI晶体载流子的迁移率-寿命积提供理论指导,对获得性能优异的InI核辐射探测材料有重要帮助.
The structures of six possible native point defects（I and In vacancies, I and In antisites, I and In interstitials） that maybe exist in the orthorhombic indium iodide（InI） crystal are optimized and investigated by the first-principles calculations based on density functional theory. The levels of difficulty in forming defects in their growth processes are obtained by calculating the defect energy levels; the position of each kind of energy level of native point defect and its effect on carrier transport are analyzed via calculating the density of states. The results show that the dominant low-energy defect of In interstitial induces a recombination center and a deep hole trap： the former shortens the lifetime of the minority carriers and the latter captures the holes from the valence band, thereby reducing the mobility-lifetime product of the hole. The calculation results provide a theoretical guidance for improving the mobility-lifetime product of carriers in InI crystal and also are helpful in obtaining the excellent materials for detecting the nuclear radiation of InI crystal.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2013年第24期129-135,共7页
Acta Physica Sinica
基金
河北省应用基础研究计划重点基础研究项目(批准号:13961103D)
中国电子科技集团公司第四十六研究所创新基金(批准号:CJ20120208)资助的课题~~
关键词
碘化铟
形成能
缺陷能级
深空穴陷阱
InI
formation energy
defect energy levels
deep hole trap
