The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 14, 2006
Filed:
Oct. 08, 2002
Chien Ping Lee, Fremont, CA (US);
Hin Fai Chau, Fremont, CA (US);
Nanlei Larry Wang, Palo Alto, CA (US);
Clarence John Dunnrowicz, Santa Cruz, CA (US);
Yan Chen, Fremont, CA (US);
Barry Jia-fu Lin, Cupertino, CA (US);
Chien Ping Lee, Fremont, CA (US);
Hin Fai Chau, Fremont, CA (US);
Nanlei Larry Wang, Palo Alto, CA (US);
Clarence John Dunnrowicz, Santa Cruz, CA (US);
Yan Chen, Fremont, CA (US);
Barry Jia-Fu Lin, Cupertino, CA (US);
WJ Communications, Inc., San Jose, CA (US);
Abstract
The safe-operating area (SOA) in a heterojunction bipolar transistor (HBT) is improved by providing a collector region in the transistor having a graded (uniformly or stepped) doping between the base region and the underlying subcollector region with the collector doping being lower near the base and higher near the subcollector and with the collector doping being less than the doping of the subcollector. The non-uniformly doped collector reduces Kirk effect induced breakdown when collector current increases.