Patent · US Expired

Correction method leading to a uniform threshold voltage distribution for a flash eprom

US5608672A · kind A · utility

9Cited by
4References
1Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 26, 1995
Grant dateMar 4, 1997
Priority date
Expiry dateSep 26, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/3409
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method for correcting over-corrected memory cells in a flash EPROM. The flash EPROM includes an array of memory cells (25), where each of the cells includes a gate 18, a floating gate (16), a source (12), a drain (14), and a substrate (10). The method includes bulk erasing each of cells in the array of cells (step 40), which results in a plurality of over-erased cells. The over-erased cells are then corrected (step 42), which results in a plurality of over-corrected cells. The over-corrected cells are identified (step 44) and selectively erased (step 46), such that a uniform threshold voltage distribution (54) is provided for the cells in the flash EPROM.

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