Reprogramming memory cells to tighten threshold voltage distributions and improve data retention
US10964402B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 19, 2020 |
| Grant date | Mar 30, 2021 |
| Priority date | — |
| Expiry date | Feb 19, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10B43/35
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Techniques are described for reprogramming memory cells to tighten threshold voltage distributions and improve data retention. In one aspect, the memory cells of a word line WLn are reprogrammed after programming of memory cells of an adjacent, later-programmed word line WLn+1. The reprogramming can be limited to lower state memory cells of WLn which are adjacent to lower state memory cells of WL+1. A program pulse magnitude used in the reprogramming can be tailored to the data states of the WLn memory cell and the adjacent, WLn+1 memory cell. In some cases, the program pulse magnitudes can be grouped to reduce the implementation complexity and time. The reprogramming can occur after an initial program operation has completed, during an idle time of a control circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.