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:
Jan. 04, 2005
Filed:
Jan. 24, 2002
Tsunenori Yamauchi, Kawasaki, JP;
Tsunenori Yamauchi, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
The semiconductor device comprises a first semiconductor layerformed on a semiconductor substrate; an outgoing base electrodeformed on the first semiconductor layer; a base layerformed on the first semiconductor layer, connected to the outgoing base electrode at a side surface of the outgoing base electrode, and formed of silicon germanium containing carbon; and a second semiconductor layerformed on the base layer. The base layerof silicon germanium contains carbon, which prevents the action of interstitial silicon atoms, which are very influential to diffusion of boron. As a result, when the emitter layer, etc. are subjected to heat processing at, e.g., about 950° C., the diffusion of boron out of the base layercan be prevented.