Time Dependence of the Reverse Current in Amorphous Silicon Schottky Diodes

Abstract

ABSTRACTWe present measurement results of the time-dependent reverse current in amorphous silicon Schottky diodes for a broad range of bias voltage stress conditions. The resultant behavior can be divided into three regimes, depending on the bias. At low biases, the reverse current exhibits a power-law dependence attributable to dispersive electron transport. In the medium bias regime, the current shows a dramatic increase which may be due to enhanced thermionic emission and tunneling of electrons across the barrier, enabled by hole transport to the metal-semiconductor interface. At high biases, the effects of prolonged stress were found to be irreversible. Here, an eventual decrease in reverse current was observed, with an associated loss of rectifying characteristics.