Nonvolatile semiconductor memory device
US8199579B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 9, 2010 |
| Grant date | Jun 12, 2012 |
| Priority date | — |
| Expiry date | Sep 9, 2030 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11C2211/5621
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
A nonvolatile semiconductor memory device includes a control circuit configured to control a soft program operation of setting nonvolatile memory cells to a first threshold voltage distribution state of the nonvolatile memory cells. When a characteristic of the nonvolatile memory cells is in a first state, the control circuit executes the soft program operation by applying a first voltage for setting the nonvolatile memory cells to the first threshold voltage distribution state to first word lines, and applying a second voltage higher than the first voltage to a second word line. When the characteristic of the nonvolatile memory cells is in a second state, the control circuit executes the soft program operation by applying a third voltage equal to or lower than the first voltage to the first word lines and applying a fourth voltage lower than the second voltage to the second word line.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.