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:
Dec. 28, 1993
Filed:
Jul. 29, 1991
Keiji Ogawa, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
The semiconductor protection device has a p.sup.+ -n.sup.- -p-n.sup.+ layer construction, and an n type impurity diffusion region is selectively formed in a surface portion of the pn junction. This n type impurity diffusion region is formed in a linear planar portion where substantially no electric field concentration is generated when a reverse voltage is applied to the pn junction formed between the n.sup.- type semiconductor region and the p type semiconductor region. Further, an electrode is provided in ohmic contact with both of the p type semiconductor region and the n.sup.+ type semiconductor region. This electrode is selectively made in contact with the p type semiconductor region at a position remote from the n type impurity diffusion region and adjacent to a curved planar portion of the pn junction where the electric field concentration tends to occur when a reverse voltage is applied to the pn junction formed between the n.sup.- type semiconductor region and the p type semiconductor region.