US 12,261,585 B2
Elastic wave device and method for manufacturing the same
Yutaka Kishimoto, Nagaokakyo (JP)
Assigned to MURATA MANUFACTURING CO., LTD., Kyoto (JP)
Filed by Murata Manufacturing Co., Ltd., Nagaokakyo (JP)
Filed on Oct. 18, 2021, as Appl. No. 17/503,415.
Application 17/503,415 is a continuation in part of application No. 15/679,324, filed on Aug. 17, 2017, granted, now 11,152,914.
Application 15/679,324 is a continuation of application No. PCT/JP2016/057411, filed on Mar. 9, 2016.
Claims priority of application No. 2015-051816 (JP), filed on Mar. 16, 2015.
Prior Publication US 2022/0038073 A1, Feb. 3, 2022
Int. Cl. H03H 9/17 (2006.01); H03H 9/13 (2006.01)
CPC H03H 9/17 (2013.01) [H03H 9/13 (2013.01)] 16 Claims
OG exemplary drawing
 
1. An elastic wave device comprising:
a piezoelectric layer including a first main surface and a second main surface facing the first main surface;
an acoustically reflective layer on the first main surface of the piezoelectric layer;
an excitation electrode on the second main surface of the piezoelectric layer; and
a support layer; wherein
the acoustically reflective layer overlaps at least the excitation electrode in a plan view of the piezoelectric layer from a second main surface side;
the support layer surrounds the acoustically reflective layer in the plan view of the piezoelectric layer from the second main surface side such that, in the plan view of the piezoelectric layer from the second main surface side, an outer periphery of the acoustically reflective layer is inside of an outer periphery of the support layer; and
an acoustic impedance of the support layer is different from an acoustic impedance of the acoustically reflective layer.