A Power MOSFET With P-Base Schottky Diode and Built-In Channel Diode for Fast Reverse Recovery

A power MOSFET with P-base Schottky diode and built-in channel diode is proposed and numerically investigated in this article. The P-base Schottky diode formed by the P-base Schottky contact is in reverse series with the P-base/N-drift junction diode. Besides, by coupling the gate of the dummy MOSFET to the source, a built-in channel diode is introduced, which provides a unipolar reverse conduction current path and drastically reduces the gate-to-drain charge. When the proposed MOSFET serves as the freewheeling diode, the reverse-biased P-base Schottky diode inactivates the P-base/N-drift junction diode, so that the reverse current will be carried out by the built-in channel diode. As a result, in comparison with the planar gate power MOSFET, the reverse recovery charge and the gate-to-drain charge could be reduced by 96.9 % and 75.4%, respectively.