High speed high density nand-based 2T-NOR flash memory design
US8773903B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2012 |
| Grant date | Jul 8, 2014 |
| Priority date | — |
| Expiry date | Jun 28, 2032 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B41/30
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A two transistor NOR flash memory cell has symmetrical source and drain structure manufactured by a NAND-based manufacturing process. The flash cell comprises a storage transistor made of a double-poly NMOS floating gate transistor and an access transistor made of a double-poly NMOS floating gate transistor, a poly1 NMOS transistor with poly1 and poly2 being shorted or a single-poly poly1 or poly2 NMOS transistor. The flash cell is programmed and erased by using a Fowler-Nordheim channel tunneling scheme. A NAND-based flash memory device includes an array of the flash cells arranged with parallel bit lines and source lines that are perpendicular to word lines. Write-row-decoder and read-row-decoder are designed for the flash memory device to provide appropriate voltages for the flash memory array in pre-program with verify, erase with verify, program and read operations in the unit of page, block, sector or chip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.