A consistent gate and substrate current model for submicron MOSFET´s by considering energy transport

Accurate modeling of the hot electron induced gate and substrate currents is of considerable importance for submicron MOS devices. In this paper, a new approach based on the simplified two-dimensional energy balance equations by incorporating the effect of transversal electric field and energy-dependent saturation velocity and relaxation time is presented. Substrate current characteristics can be predicted from the calculated energy dependent impact ionization rate. A consistent gate current is also obtained by using the same set of parameter values. Results of the gate and substrate currents present very good agreement with the experiment for a wide range of biases and channel lengths. Moreover, the conventional drift-diffusion approach tends to overestimate the calculated substrate current, while the new approach has solved the problem without difficulty