High frequency noise in fully overlapped lightly doped drain MOSFETs

The high frequency noise of fully overlapped lightly doped drain (FOLD) MOSFETs incorporating the field dependent mobility and the bias dependent series resistance is predicted. This includes the thermal noise and the induced gate noise. The results so obtained for effective current noise gain are compared with the simulated data of short channel LDD MOSFETs and are in good agreement. At frequencies much below the cut-off frequency, the induced gate noise is just 1% or even less of the drain noise. The effective current noise gain in FOLD and LDD MOSFETs is compared and shows that thermal noise increases while gate induced noise decreases with the decrease in channel length. (C) 2002 Elsevier Science B.V. All rights reserved.