Nonvolatile semiconductor memory device
US5889304A · kind A · utility
89Cited by
1References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1997 |
| Grant date | Mar 30, 1999 |
| Priority date | — |
| Expiry date | Jun 27, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D30/6891
Abstract
Disclosed is the memory cell of an EEPROM having a p-type silicon substrate and a floating gate formed on this silicon substrate via a tunnel oxide film. The element region set in the silicon substrate projects from the surface of a trench-type element isolation region. The projecting element region has a curved portion for increasing the density of tunnel electric current, and is rounded to concentrate the tunnel electric current as far as no breakdown occurs in the tunnel oxide film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.