Patent · US Expired

Micro-cavity MEMS device and method of fabricating same

US7394332B2 · kind B2 · utility

45Cited by
2References
18Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 1, 2005
Grant dateJul 1, 2008
Priority date
Expiry dateApr 10, 2026

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/49147
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A MEM switch is described having a free moving element within in micro-cavity, and guided by at least one inductive element. The switch consists of an upper inductive coil; an optional lower inductive coil, each having a metallic core preferably made of permalloy; a micro-cavity; and a free-moving switching element preferably also made of magnetic material. Switching is achieved by passing a current through the upper coil, inducing a magnetic field in the coil element. The magnetic field attracts the free-moving magnetic element upwards, shorting two open wires and thus, closing the switch. When the current flow stops or is reversed, the free-moving magnetic element drops back by gravity to the bottom of the micro-cavity and the wires open. When the chip is not mounted with the correct orientation, gravity cannot be used. In such an instance, a lower coil becomes necessary to pull the free-moving switching element back and holding it at its original position.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.