利用射频溅射方法制备了非晶态 Hg1－xCdxTe薄膜(x＝0, 0.22, 0.50, 0.66, 1), 在 80 K～300 K温度范围内, 研究了 Cd组分 x对暗电导的影响。当温度 T＞210 K时, 随着 Cd组分增加, 暗电导减小; 当温度 T＜210 K, 随着 Cd组分增加, 则暗电导增大; 当温度 T＝210 K时, 暗电导几乎与 Cd组分无关。这可能是由于随着 Cd组分增加, 薄膜中的缺陷增加所致。 a-Hg1－xCdxTe(x＝0、0.22、0.50、 0.66和 1)薄膜中存在扩展态电导和局域态电导, Cd组分 x越大, 两种导电机制的转变温度 Tm也越高。在 T＝300 K时, 利用暗电导的激活能估算出了非晶态 Hg1－xCdxTe薄膜的迁移率隙 Eg, 随着 Cd组分 x增加, 迁移率隙 Eg微弱减小。

The compositional dependence of electrical conductivity of amorphous Hg1.xCdxTe(x＝0, 0.22,0.50, 0.66 and 1) thin films by RF sputtered technique in the range of 80 K～300 K is investigated. The results indicate that the dark conductivity decreases with Cd composition at high temperature range (T＞210K), increases with Cd composition at low temperature range (T＜210 K) and is independent of Cd composition at T＝210 K. This is explained in terms of the increase in the density of defect states with increase of Cd composition in a-Hg1.xCdxTe thin films. There are two conduction mechanisms in the localized states and in the extended states for the a-Hg1.xCdxTe films. The transform temperature(Tm) from conduction in the localized states to conduction in the extended states will rise with increase of Cd composition. The mobility band gap Eg of a-Hg1.xCdxTe thin films is calculated as a function of Cd composition at T＝300 K. The mobility band gap Eg of a- Hg1.xCdxTe thin films decreases tardily with the increase of Cd composition.