Patent · US Expired

Thin film bulk acoustic wave resonator

US6870445B2 · kind B2 · utility

17Cited by
6References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 27, 2003
Grant dateMar 22, 2005
Priority date
Expiry dateApr 15, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH03H2003/0442
  • WIPO fieldBasic communication processes
  • WIPO sectorElectrical engineering

Abstract

The present invention is intended to provide a thin film bulk acoustic wave resonator, which has a resonant excitation portion free from damage caused by etching, a high electromechanical coupling coefficient kt2 and a high quality coefficient Q value, and to provide a thin film bulk acoustic wave resonator having a plurality of different resonant frequencies, which can be formed on the same substrate without increasing number of lithography process.An internal cavity is provided in a semiconductor or insulative substrate such as crystal silicon. The thin film bulk acoustic wave resonator has a layered member comprising a first electrode film, a piezoelectric film and a second electrode film on a thin wall of e.g. single crystal over the internal cavity.

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