Space-charge-limited currents through chromium-cadmium sulphide-chromium diodes

One carrier space-charge-limited current is studied in Cr---CdS---Cr diodes or sandwiches prepared by vapour deposition technique. The ohmic contacts with CdS are made of evaporated chromium. The current voltage characteristics are measured by the slowly varying triangular pulses. The thickness of the CdS films are in the range of 0·2-0·5 μ as estimated by the weight difference method. It has been observed that at low voltages, the ohmic region is dominant whereas at higher voltages a v<SUP>3/2</SUP>/d<SUP>5/2</SUP> dependence of current is found. A theoretical relationship between the voltage and the current density is obtained assumingE<SUP>−1/2</SUP> dependence of mobility which is in agreement with the experimental results