Power MOSFETs having Schottky barrier drain contact

Abstract

A new vertical Schottky barrier gain com tact power MDS~-(KSMISIT) is presented for the first time. The new device has a mique drain structure of Schottky barrier (SB) contact or p-n jvlction ad&d in para1 le1 with the SB contact. istics changes with varying the kind of barrier metal (Pt. and A I ) and the ratio of the SB contact to the total back-surface area. The change arises fran the control of the minority carrier injection resulting in conductivity mo&lation and of the electron conduction path &ring turn off. The VsDMOsms provide hi& blocking voltage, low on-state resistance and fast switching speed. 1000-1200V VQMXFEr with 100% Pt SB contact, for exwle, exhibits about a half of the on-state resistance and the carparable fa1 I time for the conventiwl power NEFEL The omstate resistance and the switching character-