Title:
RESONATOR AND RESONANCE DEVICE
Document Type and Number:
WIPO Patent Application WO/2019/064663
Kind Code:
A1
Abstract:
In order to suppress the influence on vibration of the resonator of an electric charge on an insulator layer on a resonator or of a conductive layer on the insulator layer, this resonance device is provided with: a vibration unit comprising an upper electrode and a lower electrode, a piezoelectric film which is provided between the upper electrode and the lower electrode, has a primary surface facing the upper electrode, and which causes the vibration unit to vibrate in a prescribed vibration mode when a voltage is applied between the upper electrode and the lower electrode, a protective film which is provided facing the principal surface of the piezoelectric film with the upper electrode held therebetween and which is exposed in a first region of the vibration unit, a conductive film which is provided facing the aforementioned principal surface of the piezoelectric film with the protective film held therebetween and which is exposed in a second region, which is a region adjacent to the first region of the vibration unit, and a connection electrode which is formed on the protective film and electrically connects the conductive film to the lower electrode; a holding unit which is provided so as to surround at least part of the vibration unit; and a holding arm which connects the vibration unit and the holding unit. The upper electrode is formed such that the surface area of the region overlapping the conductive film is no more than half of the total surface area of the conductive film, or is formed to avoid the region of overlap with the conductive film.
Inventors:
INOUE YOSHIHISA (JP)
KAWAI RYOTA (JP)
KAWAI RYOTA (JP)
Application Number:
PCT/JP2018/016719
Publication Date:
April 04, 2019
Filing Date:
April 25, 2018
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/24
Domestic Patent References:
| WO2016159022A1 | 2016-10-06 | |||
| WO2017090380A1 | 2017-06-01 | |||
| WO2017208568A1 | 2017-12-07 |
Foreign References:
| JP2014107817A | 2014-06-09 |
Attorney, Agent or Firm:
INABA, Yoshiyuki et al. (JP)
Download PDF: