Patent · US Expired

Angular speed sensor and method for fabricating the same

US7260990B2 · kind B2 · utility

6Cited by
7References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 23, 2005
Grant dateAug 28, 2007
Priority date
Expiry dateJun 23, 2025

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T29/42
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Provided are an angular velocity sensor with improved reliability by preventing an electric short circuit resulting from etching debris left on the bottom electrode after the etching of the conductive layers, and a method for manufacturing the angular velocity sensor. The drive electrode unit, the monitor electrode unit and the sensing electrode unit are each provided with bottom electrode (29) formed on substrate (33) having the shape of a tuning fork, piezoelectric film (30) made of piezoelectric material and formed on bottom electrode (29), and top electrode (31) formed on piezoelectric film (30). Ends (31T) of top electrode (31) are located inside ends (30T) of piezoelectric film (30) so as to expose ends (30T) of piezoelectric film (30) beyond top electrode (31), thereby forming exposed parts (32). When exposed parts (32) have a thickness of “t”, piezoelectric film (30) is made to have an exposed width (L) of not less than 0.3 t.

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