CMOS-compatible MEM switches and method of making
US6667245B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 13, 2001 |
| Grant date | Dec 23, 2003 |
| Priority date | — |
| Expiry date | May 16, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H2001/0057
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A microelectromechanical (MEM) switch is fabricated inexpensively by using processing steps which are standard for fabricating multiple metal layer integrated circuits, such as CMOS. The exact steps may be adjusted to be compatible with the process of a particular foundry, resulting in a device which is both low cost and readily integrable with other circuits. The processing steps include making contacts for the MEM switch from metal plugs which are ordinarily used as vias to connect metal layers which are separated by a dielectric layer. Such contact vias are formed on either side of a sacrificial metallization area, and then the interconnect metallization is removed from between the contact vias, leaving them separated. Dielectric surrounding the contacts is etched back so that they protrude toward each other. Thus, when the contacts are moved toward each other by actuating the MEM switch, they connect firmly without obstruction. Tungsten is typically used to form vias in CMOS processes, and it makes an excellent contact material, but other via metals may also be employed as contacts. Interconnect metallization may be employed for other structural and interconnect needs of the ME…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.