1/f electrical noise due to space charge regions

This paper shows how a backgating noise coming from boundary space charge regions becomes a 1/f resistance noise due to the biasing of the samples. This overseen noise that is Lorentzian with no bias applied, becomes a continuous set of Lorentzian terms in biased samples that synthesizes a 1/f resistance noise. The ratio fhigh/flow for the frequency band where 1/f noise appears is an exponential function of the bias voltage measured in thermal voltage units VT = kT/q at the temperature T of the experiment. Grain boundaries and planar interfaces are powerful sources of this 1/f electrical noise.