Title:
ELASTIC WAVE DEVICE, HIGH-FREQUENCY FRONT END CIRCUIT, AND COMMUNICATIONS DEVICE
Document Type and Number:
WIPO Patent Application WO/2018/235731
Kind Code:
A1
Abstract:
An elastic wave device (1) having, laminated in order therein: a support substrate (51); an acoustic reflection layer (56); a piezoelectric layer (52); and wiring electrodes (41 and 42) and an IDT electrode (110) comprising a pair of comb-like electrodes. The acoustic reflection layer (56) has: a low Z dielectric layer (53B); a high Z dielectric layer (55) arranged below the low Z dielectric layer (53B) and having a higher acoustic impedance than the low Z dielectric layer (53B); and a metal layer (54) arranged above the low Z dielectric layer (53B) and having a higher acoustic impedance than the low Z dielectric layer (53B). When the acoustic reflection layer (56) is viewed in the planar view, the formation area of the metal layer (54) is smaller than the formation area of the high Z dielectric layer (55), in a region that includes the IDT electrode (110) and the wiring electrodes (41a, 41b, 42a, 42b) and does not include IDT electrodes other than the IDT electrode (110).
Inventors:
KISHIMOTO YUTAKA (JP)
Application Number:
PCT/JP2018/022872
Publication Date:
December 27, 2018
Filing Date:
June 15, 2018
Export Citation:
Assignee:
MURATA MANUFACTURING CO (JP)
International Classes:
H03H9/25
Domestic Patent References:
| WO2016147688A1 | 2016-09-22 | |||
| WO2016147986A1 | 2016-09-22 | |||
| WO2012086441A1 | 2012-06-28 |
Attorney, Agent or Firm:
YOSHIKAWA, Shuichi et al. (JP)
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