Monte Carlo analysis of voltage noise in sub-micrometre semiconductor structures under large-signal regime

Abstract

Using an ensemble Monte Carlo technique, we investigate voltage noise(related to diffusion noise sources) in GaAs n+nn+ structures operating underlarge-amplitude periodic signals. A pronounced noise contribution aroundthe frequency of the excitation signal f0 is evidenced. This contribution is mainly associated with the time-varying field sustained by the n region. Its presence and importance depends on the length of the n region and the value of f0. This additional contribution in the voltage noise spectrum tends to disappear for values of f0 beyond the cut-off of the noise related to the n region. On the other hand, the level of low-frequency noise under large-signal conditions is higher than under mall-signal operation due to theincrease of the effective resistance of the structures.