Title:
FILM BULK ACOUSTIC RESONATOR, PIEZOELECTRIC THIN FILM DEVICE AND METHOD FOR MANUFACTURING THE PIEZOELECTRIC THIN FILM DEVICE
Document Type and Number:
WIPO Patent Application WO/2007/119643
Kind Code:
A1
Abstract:
A film bulk acoustic resonator (10) includes substrates (11, 12) having an oscillation
space (20), and a piezoelectric laminated structure (14) arranged to face the
oscillation space (20). The piezoelectric laminated structure (14) is provided
with at least a lower electrode (15), a piezoelectric thin film (16) and an upper
electrode (17), which are arranged in sequence from the side close to the oscillation
space (20). A lower insulating layer (13) is formed in contact with the lower
surface of the lower electrode (15), and an upper insulating layer (23) is formed
in contact with the lower surface of the upper electrode (17). A side spacer (26)
made of a material different from that of the electrode is arranged on the outer
circumference of the lower electrode (15) and the upper electrode (17). A step
on an interface between the side spacer (26) and the electrodes (15, 17) is less
than 25nm. The piezoelectric thin film (16) is composed of aluminum nitride.
The acoustic impedance of the side spacer (26) is larger than the acoustic impedances
of the electrodes (15, 17).
Inventors:
YAMADA TETSUO (JP)
NAGAO KEIGO (JP)
NAGAO KEIGO (JP)
Application Number:
PCT/JP2007/057379
Publication Date:
October 25, 2007
Filing Date:
April 02, 2007
Export Citation:
Assignee:
UBE INDUSTRIES (JP)
YAMADA TETSUO (JP)
NAGAO KEIGO (JP)
YAMADA TETSUO (JP)
NAGAO KEIGO (JP)
International Classes:
H03H9/17; H01L41/083; H01L41/09; H01L41/18; H01L41/187; H01L41/22; H01L41/29; H01L41/39; H03H3/02
Domestic Patent References:
| WO1999037023A1 | 1999-07-22 | |||
| WO2005060091A1 | 2005-06-30 |
Foreign References:
| JP2005303781A | 2005-10-27 | |||
| JP2006013839A | 2006-01-12 | |||
| JP2006217188A | 2006-08-17 | |||
| JP2005333619A | 2005-12-02 |
Attorney, Agent or Firm:
YAMASHITA, Johei (Toranomon 40th MT Bldg.1-3-1, Toranomon 5-chom, Minato-ku Tokyo 01, JP)
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