Dissolvable dielectric method
US5953626A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 5, 1996 |
| Grant date | Sep 14, 1999 |
| Priority date | — |
| Expiry date | Jun 5, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/7682
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A fabrication process that produces an air gap dielectric in which a multi-level interconnect structure is formed upon a temporary supporting material. The temporary material is subsequently dissolved away leaving behind an intralevel and an interlevel dielectric comprised of air. In one embodiment of the invention, a first interconnect level is formed on a barrier layer. A temporary support material is then formed over the first interconnect level and a second level of interconnect is formed on the temporary support material. Prior to formation of the second interconnect level, a plurality of pillar openings are formed in the temporary material and filled with a conductive material. In addition to providing a contact between the first and second level of interconnects, the pillars provide mechanical support for the second interconnect level. The temporary material is dissolved in a solution that attacks the temporary material but leaves the interconnect material and pillar material intact. In one embodiment of the invention, a passivation layer is formed on the second interconnect level prior to dissolving the temporary material. The air gap dielectric can be used with more than t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.