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:
Jun. 25, 1991
Filed:
Oct. 12, 1990
Ryuji Yamamura, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A semiconductor input protection device is disclosed which comprises a well type punch-through transistor consisting of a pair of parallel-opposed well layers through intermediation of a field oxide film, one of which is connected to an input terminal and the other to a reference potential. The device further comprises an impurity diffusion layer resistance with an end thereof connected to the input terminal. The lower limit distance between the opposed sides of the well layers to each other and the channel stopper is set to be smaller than that between the channel stopper and the input terminal-side well layer in the area where the latter and the impurity diffusion layer resistance intersect. The two lower limit distances depend on punch-through voltage, the width of the depletion layer in the well layer at applied punch-through voltage, and the junction disruptive strength of the well layer.