Method of manufacturing a nonvolatile semiconductor memory
US5290723A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 25, 1992 |
| Grant date | Mar 1, 1994 |
| Priority date | — |
| Expiry date | Sep 25, 2012 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/954
Abstract
A method of manufacturing a nonvolatile semiconductor memory including forming a first insulating film, a first semiconductor film for forming floating gates, a second insulating film, and a second semiconductor film for forming control gates in that order on a semiconductor substrate, and forming etching masks, each having a configuration corresponding to that of the floating gate, at every other one of areas on the second semiconductor film where the floating gates are to be formed. Side wall spacers are formed on both side walls of each of the etching masks and a third semiconductor film, formed of the same material as that of the second semiconductor film is selectively grown on parts of the second semiconductor film which are not covered by any of the etching masks and the side wall spacers. Then the side wall spacers are removed and the second semiconductor film under the side wall spacers, the second insulating film and the first semiconductor film, together with the third semiconductor film in a direction substantially perpendicular to a surface of the semiconductor substrate by using the etching masks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.