Preparation and electrical characterization of Cd0.8Zn0.2Te/Si thin films

Thin films of Cd0.8Zn0.2Te/Si structures were prepared by vacuum evaporation technique. The electrical properties such as activation energy, barrier height, and transport mechanism along with the capacitance-voltage characteristics are analyzed. The zero field activation energy calculated from the saturation current density with the inverse absolute temperature is found to be 0.37eV and the barrier height is 0.54eV. As the applied bias voltage increases the activation energy decreases from 0.3 to 0.22eV for the bias range of 0-2V. From the observed current voltage characteristics it is found that the surface state density is high for the films deposited at room temperature. From the high-frequency (I M Hz) C-V measurement the built in voltage is found to be 0.15 V. The plot of 1/C-2 vs the applied bias voltage behaviour is linear, indicating the presence of abrupt junction. The acceptor concentration as obtained from the 1/C-2 VS bias voltage is 1.4 x 10(16)cm(-3). (C) 2003 Elsevier Ltd. All rights reserved.