Patent · US Expired

Bimetallic diaphragm with split hinge for microactuator

US5271597A · kind A · utility

44Cited by
7References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 29, 1992
Grant dateDec 21, 1993
Priority date
Expiry dateMay 29, 2012

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF16K2099/0074
  • WIPO fieldMechanical elements
  • WIPO sectorMechanical engineering

Abstract

A microactuator of a silicon substrate having a frame with a central circular flexible diaphragm suspended from the substrate by a hinge. The hinge is a layer of silicon dioxide of uniform thickness which is formed by etching a groove in the silicon substrate and then conformally forming a silicon dioxide layer of uniform thickness in the groove. The substrate backside is then etched to the desired diaphragm thickness, exposing the bottom portion of the silicon dioxide layer which thereby becomes the hinge. Further a split hinge structure includes two such hinges which are parallel in part and so overlap in length, with a silicon bridge portion of the diaphragm lying therebetween. The electrical traces which extend from the frame to the central portion of the diaphragm are deposited on the silicon bridge, minimizing the mechanical stress on the traces due to hinge flexing. The resulting structure has low thermal conductivity and sufficient strength to carry the vertical loads generated by the bimetallic diaphragm. The split hinge allows the metal traces to be substantially planar with the original silicon surface.

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