AN ACCURATE ON-RESISTANCE MODEL FOR LOW-VOLTAGE VDMOS DEVICES

An accurate on-resistance model of VDMOS devices in the low voltage re gimes is proposed and verified by numerical simulation results. The mo del considers the lateral Gaussian doping profiles in the channel regi on and exact current spreading angles in the epitaxial layer for both linear and cellular geometries by employing the conformal mapping. Res ults of the proposed model are in good agreement with those of 2D and quasi-3D simulations obtained by PISCES-IIB for a VDMOS device with 10 0 V rating. The on-resistance of a low voltage VDMOS may be considerab ly overestimated if it is analyzed by the conventional method.