Method of fabricating a bipolar transistor using selective epitaxially grown SiGe base layer

US6913981B2 · kind B2 · utility

Assignee

• Micrel, Inc. · US

Inventors

• Jay A. Shideler · San Mateo, US
• Jayasimha Prasad · San Jose, US
• Ronald L. Schlupp · Los Gatos, US
• Robert W. Bechdolt · San Jose, US

Key dates

• Filing date: May 19, 2003
• Grant date: Jul 5, 2005
• Expiry date: May 19, 2023

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/177

Abstract

Embodiments of a bipolar transistor are disclosed, along with methods for making the transistor. An exemplary transistor includes a collector region in a semiconductor substrate, a base layer overlying the collector region and bound by a field oxide layer, a dielectric isolation layer overlying the base layer, and an emitter structure overlying the dielectric isolation layer and contacting the base layer through a central aperture in the dielectric layer. The transistor may be a heterojunction bipolar transistor with the base layer formed of a selectively grown silicon germanium alloy. A dielectric spacer may be formed adjacent the emitter structure and over a portion of the base layer.