Theory of the flicker noise in homogeneous nondegenerate semiconductors with single-level SRH recombination centers

Abstract

A theoretical flicker noise model for the homogeneous nondegenerate semiconductors with single-level Shockley-Read-Hall recombination centers with no spread in carrier lifetimes is presented where the dominance of the interband scattering over the intraband scattering (equivalent to the mobility fluctuations of free-charge carriers) is shown to be responsible for the flicker noise. The newly derived short-circuited excess noise spectra show all the essential features of the flicker noise in homogeneous semiconductors, i.e., in contrast to McWhorter’s model the noise spectra have no flattening at the low-frequency limit and have a frequency dependence of 1/ωγ with 1/2?γ?3/2, and as in Hooge’s empirical relation the spectra are proportional to the square of the magnitude of dc current and inversely proportional to the total number of free-charge carriers. When γ=1, the noise spectrum is independent of temperature. It is shown that γ depends strongly on the functional form of the electron capture probability cn(εc) in n-type semiconductors. It is also shown that the flicker noise in nondegenerate semiconductors with Shockley-Read-Hall recombination centers is a majority-carrier effect.