A 150-V multiple up-drain VDMOS, CMOS, and bipolar process in ´direct-bonded´ silicon on insulator on silicon

Silicon on insulator on silicon (SOIS) has been produced with silicon direct bonding (SDB). Within a silicon film of 15- mu m thickness, islands with ubiquitous oxide isolation have been formed for the simultaneous integration of 150-V power VDMOS transistors, CMOS circuits in a channelless sea-of-gates array with 2- mu m gates, and bipolar transistors. The up-drain VDMOS transistors with 2- Omega -mm/sup 2/ specific on-resistance allow multiple isolated outputs, so high-voltage push-pull drivers can be fabricated in a single chip. The bipolar transistors are comparable to those of a 60-V standard process with vertical n-p-n and lateral p-n-p current gains of 80.<>