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. 07, 2000
Filed:
Jun. 10, 1998
Hiroaki Ammo, Kanagawa, JP;
Takayuki Gomi, Tokyo, JP;
Sony Corporation, Tokyo, JP;
Abstract
A semiconductor device comprises: a substrate; a first buried layer of a first conduction type formed in the substrate; a second buried layer of the first conduction type formed in the substrate; a third buried layer of the first conduction type formed in the substrate; an epitaxial layer of the first conduction type formed on the substrate; a well region of a second conduction type formed in the epitaxial layer above the third buried layer; source/drain regions of the first conduction type formed in the well region; a first base region of the second conduction type formed in the epitaxial layer above the first buried layer; a first impurity region of the first conduction type formed on the first base region; a second base region of the second conduction type formed in the epitaxial layer above the second buried layer; a second impurity region of the first conduction type formed on the second base region; a first lead-out layer of the first conduction type connected to the first buried layer; and a second lead-out layer of the first conduction type connected to the second buried layer. The second buried layer has an impurity concentration substantially equal to that of the third buried layer.