Journal of Semiconductor Technology and Science (JSTS)
Physically, NQS (Non-Quasi-Static) effect in MOSFETs is a relaxation-time dependent phenomenon of channel charge response by a time-varying input signal. An improved non-quasi-static gate-source impedance model including a parallel RC block for short-channel MOSFETs is developed to simulate RF MOSFET input characteristics accurately in the wide range of high frequency. The non-quasi-static model parameters are accurately determined using the physical input equivalent circuit. This improved model results in much better agreements between the measured and modeled input impedance than a simple one with a non-quasi-static resistance up to 40GHz, verifying its accuracy.