Patent ID: 11916531
Assignee: TAIYO YUDEN CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. An acoustic wave device comprising:
a support substrate:
a piezoelectric layer provided over the support substrate;
a pair of comb-shaped electrodes disposed on the piezoelectric layer, each of the pair of comb-shaped electrodes including electrode fingers that excite an acoustic wave;
a temperature compensation film interposed between the support substrate and the piezoelectric layer and having a temperature coefficient of an elastic constant opposite in sign to a temperature coefficient of an elastic constant of the piezoelectric layer;
a boundary layer interposed between the support substrate and the temperature compensation film, an acoustic velocity of a bulk wave propagating through the boundary layer being higher than an acoustic velocity of a bulk wave propagating through the temperature compensation film and being lower than an acoustic velocity of a bulk wave propagating through the support substrate; and
an intermediate layer interposed between the support substrate and the boundary layer and having a Q factor less than a Q factor of the boundary layer.