Straight sidewall profile contact opening to underlying interconnect and method for making the same
US5451543A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1994 |
| Grant date | Sep 19, 1995 |
| Priority date | — |
| Expiry date | Apr 25, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/97
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for making a vertical profile contact opening (18) uses an etch stop layer (14), interposed between a conductor layer (10) and a dielectric layer (16), to eliminate resputtering of the underlying conductor material which prevents tapering of the etched opening (18). This contact opening formation is accomplished using different etchant chemistries, etching one film selective to the other. The use of the etch stop material in conjunction with conventional interconnect structures allows multiple stacking of contact features or multilevel interconnects to be achieved independent of underlying topography without increasing overall contact/via resistance. The method allows the fabrication of an unlanded via structure (30) having substantially vertical sidewall profile.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.