Numerical calculation of the field distribution and related device parameters for MOS transistors in saturation

Numerical techniques have been used to obtain the field distribution in MOS transistors under saturated bias conditions. The numerical solution of Poisson´s equation is obtained with fewer simplifying assumptions than are necessary to obtain an analytic solution. Using the numerical solution one can calculate the change in channel length as bias values are varied. From this, the changes in drain current, drain conductance, and transconductance in saturation can be predicted. The solutions also permit a rough calculation of breakdown voltages.