Optimized blocking impurity placement for SiGe HBTs

US6744079B2 · kind B2 · utility

Assignee

• International Business Machines Corporation · US

Inventors

• Basanth Jagannathan · Beacon, US
• Alvin J. Joseph · Williston, US
• Xuefeng Liu · Gaithersburg, US
• Kathryn T. Schonenberg · Wappingers Falls, US
• Ryan Wuthrich · Burlington, US

Key dates

• Filing date: Mar 8, 2002
• Grant date: Jun 1, 2004
• Expiry date: Mar 8, 2022

Classification

• Technology area (CPC H): Electricity
• CPC primary: H10D62/832

Abstract

A high performance SiGe HBT that has a SiGe layer with a peak Ge concentration of at least approximately 20% and a boron-doped base region formed therein having a thickness. The base region includes diffusion-limiting impurities substantially throughout its thickness, at a peak concentration below that of boron in the base region. Both the base region and the diffusion-limiting impurities are positioned relative to a peak concentration of Ge in the SiGe layer so as to optimize both performance and yield.