Temperature-dependent tunnelling into amorphous silicon

Abstract

Conductance measurements are presented for junctions of the type metal-oxide-amorphous silicon, where the oxide is sufficiently thin to permit tunnelling. The conductance exhibits a temperature dependence essentially identical to that for amorphous silicon with no oxide barrier present, but is several orders of magnitude smaller. A simple model, which assumes tunnelling into localized states as the dominant conduction process, is proposed to account for the temperature dependence. Using this model, an appropriate density of states in the vicinity of the Fermi level is obtained for amorphous silicon.