Temperature-dependent current-voltage characteristics and reverse leakage conduction mechanism of Pt/n-type Si0.85Ge0.15 Schottky rectifiers

We investigated the temperature dependence of the current-voltage (I-V) characteristics and the reverse leakage conduction mechanism of Pt Schottky contacts on n-type Si0.85Ge0.15 measured in the temperature range of 300 - 450 K. With increasing temperature, the Schottky barrier height and the ideality factor increased and decreased, respectively. The effective barrier height, extracted from a Richardson plot of the saturation current, was found to be 0.61 eV. A spatially inhomogeneous nature of the Pt/on n-type Si0.85Ge0.15 Schottky contact could be the main cause of the temperature dependence of the barrier height, the ideality factor, and the series resistance. The electric field dependence of the reverse leakage current showed that Schottky emission was the dominant mechanism in the reverse leakage current for all temperatures considered.