Title:
FILTER DEVICE
Document Type and Number:
WIPO Patent Application WO/2023/085189
Kind Code:
A1
Abstract:
Provided is a filter device capable of reducing losses on a high-frequency region side within a passband. A filter device 1 comprises a piezoelectric substrate, and a plurality of series-arm resonators and at least one parallel-arm resonator configured on the piezoelectric substrate, wherein, among the plurality of series-arm resonators S1 to S4, if the series-arm resonators S2 to S4, which have a relatively thick silicon oxide film, are defined as first series-arm resonators and the series-arm resonator S1, which has a relatively thin silicon oxide film, is defined as a second series-arm resonator, an antiresonant frequency of the first series-arm resonators S2 to S4 is lower than an antiresonant frequency of the second series-arm resonator S1, and if a value of (intersection width of electrode fingers of IDT electrode ÷ number of electrode fingers of IDT electrode) is defined as an aspect ratio, the aspect ratio of the first series-arm resonators S2 to S4 is greater than the aspect ratio of the second series-arm resonator S1.
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Inventors:
TAKATA TOSHIAKI (JP)
Application Number:
PCT/JP2022/041035
Publication Date:
May 19, 2023
Filing Date:
November 02, 2022
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/64; H03H9/145
Domestic Patent References:
| WO2012176455A1 | 2012-12-27 | |||
| WO2013080461A1 | 2013-06-06 |
Foreign References:
| JP2017526254A | 2017-09-07 | |||
| JP2017220929A | 2017-12-14 | |||
| JP2019106622A | 2019-06-27 |
Attorney, Agent or Firm:
OSAKA FRONT (JP)
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