Nonvolatile semiconductor memory
US4868632A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Jul 8, 1988 |
| Grant date | Sep 19, 1989 |
| Priority date | — |
| Expiry date | Jul 8, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D30/69
Abstract
In an MONOS type nonvolatile semiconductor memory comprising a channel forming semiconductor region between source and drain regions in a surface of a substrate; a tunnel insulating film formed on the channel forming semiconductor region in the surface of the substrate, the tunnel insulating film permitting charge-injection; a silicon nitride film formed as a second insulating film on the tunnel insulating film; a silicon oxide film formed as a third insulating film; and a conductive electrode formed on the silicon oxide film, the silicon nitride film has a composition close to a stoichiometric value of Si.sub.3 N.sub.4 at a portion near an interface with the tunnel insulating film and has a composition of excess silicon at a portion of the thickness of the same film except near the interface with the tunnel insulating film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.