A model for the intrinsic gate capacitances of short channel MOSFETs

Abstract

In this paper we present a model for the gate charge and the intrinsic gate capacitances in the strong inversion regime of a short-channel MOSFET. The model accounts for various second-order effects such as carrier velocity saturation, channel-length modulation and mobility degradation. An accurate model for the d.c. characteristics is first developed which guarantees the continuity of the current and its first and second derivatives with respect to the drain voltage at the transition from the linear to the saturation region. The gate charge is then computed and the gate capacitances are derived. Finally, the theoretical predictions of the model are compared to the experimental data available from the literature.