A parametric study of power MOSFETs

The theoretical limitations of V-grooved and double-diffused power MOSFETs are studied using several design parameters as variables. The results are used to gauge the performance of currently available power MOSFETs and to project the capabilities of future devices. With proper design, the channel resistance can be negligible so that the on-state resistance is that of the bulk material (~8.3xl0^-9 V_dsB ^2.5 ??.cm²) plus the lead resistance. A transmission line effect associated with long resistive gate electrodes could limit the speed of certain devices. Devices with the capability of switching 10 kW per cm² of chip area and hundred kilowatt per package are theoretically possible over a very wide voltage range. A new structure is proposed that could raise the power capability by an order of magnitude in very high voltage devices.