A Theory of The Shot Noise in A Step Junction Having Linear Distribution of The Carrier Generation Rate

An expression for the shot noise due to carrier generation in the depletion region of a one-sided abrupt p-n junction with spatially linear distribution of the generation rate of hole-electron pairs is derived. Some characteristic features of this theory are summarized as follows : Assuming that the carrier generation rate is expressed as C(χ)=C_0(1-χ/α), where α is the characteristic length, and the noise spectrum as S(ω)=2qIГ^2,where q is the electronic charge, I the current flowing through the junction under a given bias voltage, and Г^2 the noise suppression factor, it is shown that the value of Г^2 lies between 0.64 and 1,which is a function of a and the thickness of the depletion region. An application of the theory to the junctions under illumination is presented.