The effective density of induced interface states of ionized cluster beam deposited Ag/n-Si Schottky junctions

The series of Ag/n-Si(1 1 1) Schottky junctions, prepared by the ionized cluster beam deposition method for an Ag ion acceleration voltage of U-a = 0 V, 300 V, 600 V and 1 kV, exhibits strong excess capacitances, the peaks of which gradually shift from reverse to forward bias voltages. These C-U measurements, the first such reported, are interpreted on the basis of the existence of external bias-dependent induced interfacial net charge density. It has been found that either reverse or forward excess capacitance of pertinent samples of the series is directly related to the induced interfacial charges above. From the above data an effective density of interface states is extracted which is characterized by the bias-dependent sharp spikes distributed along the semiconductor energy gap. (C) 2001 Published by Elsevier Science Ltd.