Effect of cadmium concentration and laser irradiation on photoconductivity of CdxSe100−x thin films

In this paper we have studied the effect of cadmium concentration and N2 laser irradiation on steady state, photosensitivity and transient photoconductivity of CdxSe100−x (x=54, 34) thin films, which were prepared by thermal vacuum evaporation method. Photoconductivity measurements on the thin films are carried out at different levels of light intensities at room temperature. The current-voltage characteristic shows ohmic behavior of the films. The photosensitivity of the CdxSe100−x thin films is found to decrease with increase of cadmium concentration in the system, whereas it increases after irradiation with N2 laser. Apart from this, the photocurrent follows the Iph∝Fγ law. Also, the differential lifetimes (τd) are found to increase with increase in the cadmium concentration in the CdxSe100−x thin films and also with increase in the laser irradiation time.