Fuse link structures through the addition of dummy structures
US5589706A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 31, 1995 |
| Grant date | Dec 31, 1996 |
| Priority date | — |
| Expiry date | May 31, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/952
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An improved etch behavior is promoted to generate vertical sidewalls for fuse links that will promote reliable and repeatable laser cutting of the fuse links. In one embodiment, dummy structures are added adjacent to fuse links in order to obtain the vertical sidewalls for reliable fuse deletion. The dummy structures form no part of the fuse or circuit structure but, because of the proximity of the dummy structures to the fuse links, vertical sidewalls are promoted in a reactive ion etch which is used to form the fuse array. In another embodiment, the vertical sidewalls of the fuse links are achieved in a damascene process in which grooves are formed in an oxide layer and filled with a metal. These grooves correspond to the fuse links and alternating dummy structures. Once filled, the surface is planarized using a chemical-mechanical process. The dummy structures provide reinforcement for the metallization (metal and dielectric film), maintaining the integrity of the metallization. In both embodiments, the vertical sidewalls and constant height of the resulting fuse links promote reliable laser cutting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.