Fluctuating deep‐level trap occupancy model for 1/f noise in semiconductor resistors

A quantitative theoretical model for 1/f and low‐frequency noise due to bulk traps in semiconductor resistors has been developed. The model is based on the fact that random fluctuations of the steady‐state deep‐level‐trapped electron density, at some point in a depletion layer, decay exponentially with a relaxation time which depends on the local free electron density, the intrinsic properties of the semiconductor and the trap energy. The model, which is valid for relaxation times which are much longer than the free electron transit time, was applied to the case of a Schottky‐barrier field effect resistor. Our results show that the low‐frequency noise spectrum generated by deep‐level traps with a broad spatial distribution throughout the depletion layer, is very sensitive to Fermi‐Dirac trap statistics. The discrete distribution of flatband trap energy levels is the crucial parameter which determines the spectral density and range of the low‐frequency noise. Monoenergetic traps generate a considerably bro...