近距离升华沉积CdTe掺Cd薄膜的微结构和电学、光学特性

Microstructure,electrical and optical properties of Cd-doped CdTe thin films deposited by close-spaced-sublimation

采用近距离升华技术制备了掺杂Cd元素的CdTe多晶薄膜.利用X射线衍射仪和扫描电子显微镜表征其微结构,用霍尔效应测试仪和紫外可见分光光度计分析其电学、光学特性.结果显示,适量的掺杂Cd元素可改善CdTe薄膜晶形,显著提高薄膜的电导特性,由弱的p型电导转变为导电性能良好的n型电导,但对光能隙影响不大.

Cd-doped CdTe polycrystalline films were deposited on ITO/glass substrates by close-spaced-sublimation （CSS）method. The microstructural, morphological, electrical and optical properties of the films were characterized by X-ray diffraction, scanning electron microscopy, Hall effect, and optical absorption. It is found that the crystallinity is improved, the electrical resistivity drops 4—5 orders of magnitude and the conductivity changes from p-type to n-type when pure CdTe film is doped with a proper amount of Cd. There is no obvious influence on the optical band gaps of the films by the doping of Cd.