Thin-film quasi-SOI power MOSFET fabricated by reversed silicon wafer direct bonding

Abstract

A quasi-SOI power MOSFET has been fabricated by reversed silicon wafer direct bonding. In this power MOSFET, the buried oxide under the channel and source regions is removed and the channel region is directly connected to the source body contact electrode to reduce the base resistance of the parasitic npn bipolar transistor. The quasi-SOI power MOSFET can suppress the parasitic bipolar action and shows lower specific on-resistance than that of the conventional SOI power MOSFET. The fabricated chip level quasi-SOI power MOSFET shows the specific on-resistance of 86 m/spl Omega//spl middot/mm/sup 2/ and on-state breakdown voltage of 30 V.