CdSe单晶的正电子寿命研究

Studies of the Positron Annihilation Lifetime in CdSe Crystal

利用正电子湮没方法对CdSe单晶中的缺陷进行了研究,通过对不同温度下退火样品正电子湮没寿命的测试分析,表明:在CdSe晶体中存在的点缺陷主要是占优势的镉空位。由正电子湮没寿命和退火温度的关系,研究了硒化镉单晶退火时空位的迁移、合并及消失情况,确定出能减小生长中形成的空位性缺陷浓度并获得较为完整的晶格的最佳退火温度范围为650～800℃。

Defects in CdSe crystal were investigated with Positron Annihilation Technology (PAT). Tests and analyses of the positron annihilation lifetime on annealing samples at different temperature demonstrated that point defects were mainly cadmium vacancies which were preponderant in CdSe crystal. Meanwhile, the mobile character, combination and disappearing process of the vacancies were discussed in accordance with relationships between positron annihilation lifetime and different annealing temperature. Optimal annealing temperature is in the range of 650-800°C. In this temperature range, the concentration of vacancy-type defects will decrease and integrated crystal lattice will be obtained.