Er^(3+)注入CdTe薄膜的结构和光电性能研究

Investigation on the crystal structure, optical and electrical properties of Er^(3+) implanted CdTe thin film

采用离子注入技术对近距离升华制备的CdTe薄膜进行Er3+掺杂研究.讨论了不同掺Er3+浓度对CdTe薄膜的结构和光电性能的影响.利用X射线衍射仪、扫描电子显微镜、紫外-可见分光光度计、霍耳效应测试系统和复阻抗分析仪对样品进行测试.结果表明,适当的掺杂量可以改善CdTe薄膜的结晶性能,降低晶界势垒高度,提高其导电性能.在一定掺杂范围内掺Er3+对CdTe薄膜的光能隙影响不大.

The structure, optical and electrical properties of the CdTe polycrystalline thin film prepared by close-space sublimation and doped with rare earth element erbium using ion implantation had been investigated by means of X-ray diffraction, scanning electron microscopy, ultraviolet visible spectroscopy, Hall effect and impedance measurement. The results indicate that the crystallinity of the samples can be improved with suitable doping concentration. It is believed that the grain-boundary barrier of the thin film CdTe： Er can be decreased due to the appearance of electron traps at grain boundaries. It is found that the implantation of Er^3 ＋ in CdTe thin film causes a great change in conductivity but only a little influence on optical energy band gap of the samples.