Patent · US Expired

Method of making semiconductor ROM cell programmed using source mask

US5432103A · kind A · utility

5Cited by
27References
16Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 23, 1992
Grant dateJul 11, 1995
Priority date
Expiry dateDec 23, 2012

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10B20/00

Abstract

ROM cell programmed ON has N+ source implant spaced a given distance from the gate with LDD bridging the gap between the N+ source and the N channel. ROM cell programmed OFF has P+ implanted into this gap so as to completely override the LDD in this gap. The P+ prevents the N channel from forming ohmic connection to the N+ source.

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