Patent · US Expired

Fixed resistance high density parallel ROM device

US5684733A · kind A · utility

202Cited by
1References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1996
Grant dateNov 4, 1997
Priority date
Expiry dateSep 30, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C17/126
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

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.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.