Flash memory cell and forming method thereof
US11552088B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 11, 2021 |
| Grant date | Jan 10, 2023 |
| Priority date | — |
| Expiry date | Mar 11, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/035
Abstract
A method of forming a flash memory cell includes the following steps. A first dielectric layer and a floating gate layer are deposited on a substrate sequentially. Three blocking structures having oblique sidewalls broaden from bottom to top penetrating through the first dielectric layer and the floating gate layer are formed. A first part and a second part of the floating gate layer between two adjacent blocking structures are etched respectively, so that a first floating gate having two sharp top corners and oblique sidewalls, and a second floating gate having two sharp top corners and oblique sidewalls, are formed. The three blocking structures are removed. A first isolating layer and a first selective gate covering the first floating gate are formed and a second isolating layer and a second selective gate covering the second floating gate are formed. A flash memory cell formed by said method is also provided.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.