The theory of inherent noise in p-n junction diodes and bipolar transistors

A new calculation is made of the noise (excluding excess noise) in p-n junction diodes and bipolar transistors. The theory is based on an analysis of the current waveforms caused by thermal motion of individual carriers and by individual recombination events in a one-dimensional model; unlike that of van der Ziel (1955) it does not rely on arbitrary assumptions about thermal fluctuations in carrier concentration and does not involve a transmission-line analogy. When depletion-layer recombination effects are neglected, the results are found to be identical to those obtained by van der Ziel, although one of his postulates was invalid. The theory of van der Ziel and Becking (1958) which also leads to the same results does not appear to be consistent with the new treatment.