SIMPLE-MODEL FOR THE SATURATION VOLTAGE AND CURRENT OF SUBMICRON MOSFETS

A simple but reasonably accurate model is presented for the saturation voltage and current of submicron MOSFETs in strong inversion. Relevant device physics such as the effects of short channel, narrow channel, and the voltage drop along the channel caused by the drain voltage are accounted for in a first-order manner. The conventional model is also derived from the present model by employing several approximations. It is shown that the present model compares more favourably with PISCES device simulation results and that the conventional model can overestimate the saturation I-V characteristics by about 30% for a typical submicron MOSFET. We further suggest that the error caused by the conventional model is smaller for a MOSFET having a shorter channel, a wider channel, or/and a lower impurity doping concentration.