Temperature dependence of current-voltage characteristics of Ag/p-SnSe Schottky diodes

The current-voltage (I-V) characteristics of Ag/p-SnSe Schottky barrier diodes were measured in the temperature range 80-350 K. We have tried to determine some intrinsic and contact properties such as barrier heights, ideality factor, series resistance and carrier concentrations. The apparent barrier height and the ideality factor calculated by using thermionic emission (TE) theory were found to be strongly temperature dependent. Evaluating forward I-V data reveals a decrease at the zero-bias barrier height (Phi(BO)), but an increase at the ideality factor (n) with decrease in temperature, and these changes are more pronounced below 200 K. It is shown that the values of R-s estimated from Cheung's method were strongly temperature dependent and decreased with increasing temperature. From the reverse-bias I-V graphs, it is found that the experimental carrier density (N-A) values increased with increasing temperature. The conventional Richardson plot exhibits non-linearity below 200 K with the linear portion corresponding to activation energy of 0.35 eV. It has been found that all contacts are of Schottky type. (C) 2004 Elsevier B.V. All rights reserved.