Patent ID: 11942921
Assignee: MURATA MANUFACTURING CO., LTD.
Field: Basic communication processes (Electrical engineering)
Classification: CPC H | IPC H

Claim 0:
1. An acoustic wave device comprising:
a piezoelectric layer;
an interdigital transducer (IDT) electrode located on the piezoelectric layer;
a high-acoustic-velocity member positioned on an opposite side of the piezoelectric layer from the IDT electrode such that an acoustic velocity of a bulk wave propagating through the high-acoustic-velocity member is higher than an acoustic velocity of an acoustic wave propagating through the piezoelectric layer;
a low-acoustic-velocity film provided between the high-acoustic-velocity member and the piezoelectric layer such that an acoustic velocity of a bulk wave propagating through the low-acoustic-velocity film is lower than the acoustic velocity of the bulk wave propagating through the piezoelectric layer; and
a dielectric film located on the piezoelectric layer so as to cover the IDT electrode; wherein
a Young's modulus of the dielectric film is larger than a Young's modulus of the low-acoustic-velocity film; and
a material of the dielectric film is silicon oxide.