Patent · US Expired

Method of programming a memory cell

US6781885B1 · kind B1 · utility

2Cited by
2References
7Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 5, 2003
Grant dateAug 24, 2004
Priority date
Expiry dateAug 19, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG11C16/3454
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In programming the threshold voltage of a memory cell transistor having a substrate, a gate insulator on the substrate, a floating gate on the gate insulator, an insulating layer on the floating gate, and a control gate on the insulating layer, and a source and drain in the substrate, a voltage difference is applied between the drain and source of the transistor and negative voltage is applied to the substrate of the transistor. An increasing voltage is applied to the control gate of the transistor, and, during application of that increasing voltage, a succession of verification tests are undertaken at a corresponding succession of times separated by chosen time intervals to verify if the transistor has been programmed to a chosen threshold voltage.

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