A 70-V, 90-m/spl Omega/ mm/sup 2/, high-speed double-layer gate UMOSFET realized by selective CVD tungsten

Abstract

Selective CVD is used to develop a low on-resistance, high-speed UMOSFET with a new double-layer gate electrode made of tungsten. The experimental UMOSFET has an active device area of 1 mm/sup 2/, an on-resistance of 90 m/spl Omega/ and a breakdown voltage of 70 V. Its corner frequency (-3 dB)is extended to 2.14 MHz. This value is 1.8 times higher than that of a conventional poly-Si-gate UMOSFET.