LONG-RANGE FLUCTUATIONS OF RANDOM POTENTIAL LANDSCAPE AS A MECHANISM OF 1/f NOISE IN HYDROGENATED AMORPHOUS SILICON

Abstract

We describe a mechanism that links the long-range potential fluctuations induced by charged defects to the low-frequency resistance noise widely known as 1/fnoise. This mechanism is amenable to the first principles microscopic calculation of the noise spectrum, which includes the absolute noise intensity. We have performed such a calculation for the thin films of hydrogenated amorphous silicon ( a-Si:H ) under the condition that current flows perpendicular to the plane of the films, and have found a very good agreement between the theoretical noise intensity and the measured one. The mechanism described is quite general. It should be present in a broad class of systems containing poorly screened charged defects.