A new approach for modeling the MOSFET using a simple, continuous analytical expression for drain conductance which includes velocity-saturation in a fundamental way

Abstract

A simple, analytical conduction model is presented which is continuous over both the linear and saturation regimes of device operation. It is based on an analysis of the drain conductance in which g/sub DS/ is modeled as a simple hyperbolic form from which drain characteristics are derived. The model is assessed by a chi-square curvefit analysis to show that it is extremely accurate for both long- and short-channel devices. The approach is supported by an analysis which includes the physics of velocity saturation at the fundamental level. Other short-channel effects associated with MOSFET operation may be developed with longitudinal mobility variation as the model foundation. The equation for the hyperbolic asymptotes will reduce to the traditional parabolic model of the MOSFET when classical assumptions are made for the saturation point. This feature of the model demonstrates the fundamental basis of the approach.