Low-Frequency Noise Phenomena in Switched MOSFETs

In small-area MOSFETs widely used in analog and RF circuit design, low-frequency (LF) noise behavior is increasingly dominated by single-electron effects. In this paper, the authors review the limitations of current compact noise models which do not model such single-electron effects. The authors present measurement results that illustrate typical LF noise behavior in small-area MOSFETs, and a model based on Shockley-Read-Hall statistics to explain the behavior. Finally, the authors treat practical examples that illustrate the relevance of these effects to analog circuit design. To the analog circuit designer, awareness of these single-electron noise phenomena is crucial if optimal circuits are to be designed, especially since the effects can aid in low-noise circuit design if used properly, while they may be detrimental to performance if inadvertently applie

Low-frequency noise in hot-carrier degraded nMOSFETs

This paper discusses the low-frequency (LF) noise in submicron nMOSFETs under controlled transistor aging by hot-carrier stress. Both traditional, steady-state LF noise as well as the LF noise under periodic large-signal excitation were found to increase upon device degradation, for both hydrogen passivated and deuterium passivated Si–SiO2 interfaces. As hot-carrier degradation is slower in deuterium- annealed MOSFETs, so is the increase of the noise in these devices. The noise-suppressing effect of periodic OFF switching is gradually lost during hot-carrier degradation, as the LF noise under periodic large-signal excitation increases more rapidly than the LF noise in steady-state