【摘要】 利用射频溅射方法制备了非晶态Hg_1-xCd_xTe薄膜（x=0,0.22,0.50,0.66,1）,在80 K³00 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-Hg_1-xCd_xTe（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Hg_1-xCd_xTe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。更多还原

【Abstract】 The compositional dependence of electrical conductivity of amorphous Hg_1-xCd_xTe（x=0, 0.22, 0.50, 0.66 and 1） thin films by RF sputtered technique in the range of 80 K³00 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-Hg_1-xCd_xTe thin films. There are two conduction mechanisms in the localized states and in the extended states for the a-Hg_1-xCd_xTe 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-Hg_1-xCd_xTe thin films is calculated as a function of Cd composition at T=300 K. The mobility band gap Eg of a-Hg_1-xCd_xTe thin films decreases tardily with the increase of Cd composition.更多还原