Method of fabricating micro-electromechanical switches on CMOS compatible substrates
US6798029B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 9, 2003 |
| Grant date | Sep 28, 2004 |
| Priority date | — |
| Expiry date | May 9, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2059/0072
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of fabricating micro-electromechanical switches (MEMS) integrated with conventional semiconductor interconnect levels, using compatible processes and materials is described. The method is based upon fabricating a capacitive switch that is easily modified to produce various configurations for contact switching and any number of metal-dielectric-metal switches. The process starts with a copper damascene interconnect layer, made of metal conductors inlaid in a dielectric. All or portions of the copper interconnects are recessed to a degree sufficient to provide a capacitive air gap when the switch is in the closed state, as well as provide space for a protective layer of, e.g., Ta/TaN. The metal structures defined within the area specified for the switch act as actuator electrodes to pull down the movable beam and provide one or more paths for the switched signal to traverse. The advantage of an air gap is that air is not subject to charge storage or trapping that can cause reliability and voltage drift problems. Instead of recessing the electrodes to provide a gap, one may just add dielectric on or around the electrode. The next layer is another dielectric layer which is dep…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.