Patent · US Active

Split-gate flash memory cell and fabrication method thereof

US11437475B2 · kind B2 · utility

0Cited by
2References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 18, 2021
Grant dateSep 6, 2022
Priority date
Expiry dateFeb 18, 2041

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D30/6892
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A split-gate flash memory cell includes a semiconductor substrate having thereon a select gate oxide layer and a floating gate oxide layer. A floating gate is disposed on the floating gate oxide layer. A football-shaped oxide layer is disposed on the floating gate. The floating gate includes tips under the football-shaped oxide layer. A select gate is disposed on the select gate oxide layer and extended onto the football-shaped oxide layer. An inter-poly oxide layer is between the select gate and the floating gate. The inter-poly oxide layer has a thickness smaller than a thickness of the select gate oxide layer. A source region is formed in the semiconductor substrate and adjacent to the floating gate. A drain region is formed in the semiconductor substrate and adjacent to the select gate.

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