Low frequency noise in Schottky barrier contacts of titanium nitride on n-type silicon

Abstract

The electrical characteristics and the low frequency noise of Schottky contacts on n-type Si(100) have been systematically measured. The thin films were deposited by reactive magnetron sputtering at room temperature. Based on a model of a parallel combination of an ideal diode of current and a generation-recombination diode of current , we have extracted the contribution of both diodes to the measured total current I. Treating the two components and as different noise generators, we have analysed the observed white noise at high frequencies and the excess current noise at lower frequencies. The white noise is explained by using a pure shot noise for the component , by applying Gupta's general theorem on noise in non-linear driven devices for the component and by considering an additional noise generator with a Nyquist-type intensity. The excess current noise is explained by a model based on fluctuations of the generation-recombination current only. Analysis of the versus I data allowed us to determine the interface state density.