Effect of gate resistance on high-frequency power switching efficiencies of advanced power MOSFETs

Accurate gate resistance values for large-area power MOSFETs have been obtained from calorimetric power loss measurements. It is shown that advanced power MOSFETs fabricated using refractory silicide gates exhibit a fivefold reduction in the gate resistance compared to conventional power MOSFETs with heavily POCl/sub 3/-doped polysilicon gates. Power MOSFETs with integral Schottky diodes are shown to further reduce the resistive-gate power dissipation. A simple analysis is used to evaluate the switching efficiency of power MOSFETs as a function of output current and switching frequency. >