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:
Sep. 29, 2009
Filed:
Jun. 13, 2005
Noriyuki Kodama, Kanagawa, JP;
Hitoshi Irino, Kanagawa, JP;
Noriyuki Kodama, Kanagawa, JP;
Hitoshi Irino, Kanagawa, JP;
NEC Electronics Corporation, Kanagawa, JP;
Abstract
In a semiconductor device, a well region is formed in a semiconductor substrate, a transistor-formation region is defined in the well region. An electrostatic discharge protection device is produced in the transistor-formation region, and features a multi-finger structure including a plurality of fingers. A guard-ring is formed in the well region so as to surround the transistor-formation region, and a well blocking region is formed in the well region between the transistor-formation area and the guard-ring. A substrate resistance determination system is associated with the electrostatic discharge protection device to determine a substrate resistance distribution at the transistor-formation area such that snapbacks occur in all the fingers in a chain-reaction manner, and such that occurrence of a latch-up state is suppressed.