Bipolar transistors with high voltage MOS transistors in a single substrate

US5229308A · kind A · utility

Assignee

• Xerox Corporation · US

Inventors

• Tuan A. Vo · Albany, US
• Mohamad M. Mojaradi · Los Angeles, US
• Steven A. Buhler · Redondo Beach, US

Key dates

• Filing date: May 4, 1992
• Grant date: Jul 20, 1993
• Expiry date: May 4, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10S148/009

Abstract

A method of manufacturing a semiconductor device having a bipolar transistor for ordinary logic operation, as well as a high voltage MOS transistor which are provided in a single semiconductor substrate. The process includes the steps of making high voltage MOS transistors which comprises the steps of n-well fabrication, first drift region fabrication, second drift region fabrication, source and drain contact region fabrication and making bipolar transistors within the same silicon substrate as the high voltage MOS transistors which includes the step of base region fabrication where the steps for fabricating the second drift region of the high voltage MOS transistor and the base region of the bipolar transistor are combined so that both regions are created simultaneously.