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. 07, 1997
Filed:
Oct. 26, 1995
Makio Iida, Ichinomiya, JP;
Tadashi Shibata, Toyokawa, JP;
Takayuki Sugisaka, Okazaki, JP;
Shoji Miura, Nukata-gun, JP;
Toshio Sakakibara, Nishio, JP;
Nippondenso Co., Ltd., Kariya, JP;
Abstract
A semiconductor device is provided which makes a high withstand voltage bipolar transistor small and prevents deterioration in a switching speed of the transistor. A silicon oxide layer is formed on a silicon substrate, and a semiconductor island of one conductivity type which is isolated laterally by an isolation trench is formed on the silicon oxide layer. A silicon oxide film is formed on an outer periphery portion of the semiconductor island to bury the trench. In the semiconductor island, a bipolar transistor, namely a base region of the other conductivity type, is formed, and in the base region an emitter region of one conductivity type is formed and a collector region of one conductivity type is further formed. In the semiconductor island a diffusion region of the other conductivity type for extracting excessive carriers to which a constant electric potential is applied is further formed.