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:
Jun. 04, 2002
Filed:
Mar. 07, 2001
Teruhito Ohnishi, Osaka, JP;
Akira Asai, Osaka, JP;
Takeshi Takagi, Kyoto, JP;
Tohru Saitoh, Osaka, JP;
Yo Ichikawa, Aichi, JP;
Yoshihiro Hara, Osaka, JP;
Koichiro Yuki, Osaka, JP;
Katsuya Nozawa, Osaka, JP;
Koji Katayama, Nara, JP;
Yoshihiko Kanzawa, Osaka, JP;
Matsushita Electric Industrial Co., Ltd., Kanagawa-ken, JP;
Abstract
In a bipolar transistor block, a base layer ( ) of SiGe single crystals and an emitter layer ( ) of almost 100% of Si single crystals are stacked in this order over a collector diffused layer ( ). Over both edges of the base layer ( ), a base undercoat insulating film ( ) and base extended electrodes ( ) made of polysilicon are provided. The base layer ( ) has a peripheral portion with a thickness equal to that of the base undercoat insulating film ( ) and a center portion thicker than the peripheral portion. The base undercoat insulating film ( ) and gate insulating films ( and ) for a CMOS block are made of the same oxide film. A stress resulting from a difference in thermal expansion coefficient between the SiGe layer as the base layer and the base undercoat insulating film can be reduced, and a highly reliable BiCMOS device is realized.