US 12,176,879 B2
Acoustic wave device, filter and multiplexer
Kazushige Hatakeyama, Tokyo (JP); and Jyunichi Hamasaki, Tokyo (JP)
Assigned to TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed by TAIYO YUDEN CO., LTD., Tokyo (JP)
Filed on Jun. 9, 2022, as Appl. No. 17/836,752.
Claims priority of application No. 2021-106573 (JP), filed on Jun. 28, 2021.
Prior Publication US 2022/0416757 A1, Dec. 29, 2022
Int. Cl. H03H 9/02 (2006.01); H03H 9/64 (2006.01); H03H 9/72 (2006.01)
CPC H03H 9/02574 (2013.01) [H03H 9/6483 (2013.01); H03H 9/725 (2013.01)] 13 Claims
OG exemplary drawing
 
1. An acoustic wave device comprising:
a first substrate having at least a part of a first surface that is a piezoelectric layer;
an acoustic wave element provided on the first surface of the piezoelectric layer;
a second substrate provided apart from the first substrate via the acoustic wave element and a gap;
a first metal layer provided on the first surface and conductively connected to the acoustic wave element;
a second metal layer provided on a second surface of the second substrate on a first substrate side;
a third metal layer that connects the first metal layer to the second metal layer, is thicker than the first metal layer and the second metal layer, and contains copper or silver as a main component; and
a first conductive layer that covers a side surface of the third metal layer and a third surface of the first metal layer on a second substrate side in a region surrounding another region where the third metal layer is bonded to the first metal layer, is thinner than the third metal layer, and contains a component other than copper, silver, and tin as a main component.