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:
Nov. 14, 2006
Filed:
Jun. 22, 2004
Kenji Toyoda, Osaka, JP;
Koichiro Yuki, Osaka, JP;
Takeshi Takagi, Kyoto, JP;
Teruhito Ohnishi, Osaka, JP;
Minoru Kubo, Mie, JP;
Kenji Toyoda, Osaka, JP;
Koichiro Yuki, Osaka, JP;
Takeshi Takagi, Kyoto, JP;
Teruhito Ohnishi, Osaka, JP;
Minoru Kubo, Mie, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
The bipolar transistor of the present invention includes a Si collector buried layer, a first base region made of a SiGeC layer having a high C content, a second base region made of a SiGeC layer having a low C content or a SiGe layer, and a Si cap layerincluding an emitter region. The C content is less than 0.8% in at least the emitter-side boundary portion of the second base region. This suppresses formation of recombination centers due to a high C content in a depletion layer at the emitter-base junction, and improves electric characteristics such as the gain thanks to reduction in recombination current, while low-voltage driving is maintained.