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:
Nov. 04, 1997
Filed:
Sep. 30, 1996
Applicant:
Inventors:
Assignee:
Primary Examiner:
Int. Cl.
CPC ...
G11C / ;
U.S. Cl.
CPC ...
365100 ; 365 51 ;
Abstract
The present invention provides a fixed resistance sense-routed high density parallel ROM device for maintaining the resistance of a buried N+ region on a sense route constant. When data is read from a ROM cell matrix, the selection of different ROM cell transistors does not change the resistance of the buried N+ region on the sense route and thus enables a simplified design of a sense amplifier. The inactive select gate or transfer gate that is activated by the select line can be isolated by ion implantation for forming a buried P+ isolation and thus avoiding the narrowing or the cutting-off of the width of the active transfer gate or select gate due to ion diffusion.