Method for fabricating semiconductor memory device
US5336628A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 13, 1993 |
| Grant date | Aug 9, 1994 |
| Priority date | — |
| Expiry date | Apr 13, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved integrated circuit and fabrication method for forming the improved integrated circuit is described. The method includes an anisotropic etching, without the use of either masks or photolithography, which removes insulating material from contact openings, but keeps insulating material on the sides of conductive layers, preventing inadvertent short circuits from the contact openings to the conductive layers. The maskless etching method makes it possible to avoid mask-wafer alignment errors and therefore frees designers to perfectly center contact openings within insulative regions without taking into account the surface area tolerances required under prior art fabrication methods. This freedom allows designers to design more highly integrated devices. The particular embodiments of the semiconductor integrated circuit may include floating gates (47) and control gates (52) covered with an upper oxide layer (53) on which electrical connection lines (11) have been installed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.