Method of reducing hot electron injection type of read disturb in memory
US9361993B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 21, 2015 |
| Grant date | Jun 7, 2016 |
| Priority date | — |
| Expiry date | Jan 21, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C16/3422
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
Read disturb is reduced in a charge-trapping memory device such as a 3D memory device by optimizing the channel boosting voltage in an unselected NAND string. A pass voltage applied to the unselected word lines can cause a large gradient in the channel which leads to electron-hole formation and a hot electron injection (HEI) type of read disturb. When the selected word line is close to the source-side of the NAND string, HEI disturb occurs on the drain-side of the selected word line. To avoid this disturb, a spike is provided in the control gate voltage of a drain-side selected gate transistor to temporarily connect the channel to the bit line, lowering the voltage of the associated channel region. A similar approach is used for a drain-side selected word line. The spike may be omitted when the selected word line is mid-range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.