Elastic wave device and method for manufacturing the same
AssigneeMurata Manufacturing Co., Ltd.
InventorsTetsuya KIMURA, Takashi OGAMI, Katsuya DAIMON
Life of this patent
Estimating the term…
Abstract
An elastic wave device propagating plate waves includes a stack of an acoustic reflection layer, a piezoelectric layer, and IDT electrode on a supporting substrate. The piezoelectric layer is thinner than a period of fingers of the IDT electrode. The acoustic reflection layer includes low-acoustic-impedance layers and high-acoustic-impedance layers. The low-acoustic-impedance layers are made of SiO2, and the high-acoustic-impedance layers are made of at least one material selected from the group consisting of W, LiTaO3, Al2O3, AlN, LiNbO3, SiN, and ZnO.
Claims18
An elastic wave device propagating plate waves, comprising:
- a supporting substrate;
- an acoustic reflection layer on the supporting substrate;
- a piezoelectric layer on the acoustic reflection layer;
- and
- an IDT electrode on an upper or lower surface of the piezoelectric layer, the piezoelectric layer being thinner than a period of fingers of the IDT electrode;
- wherein
- the acoustic reflection layer includes a low-acoustic-impedance layer and a high-acoustic-impedance layer having a higher acoustic impedance than an acoustic impedance of the low-acoustic-impedance layer;
- and
- the low-acoustic-impedance layer is made of SiO2, and the high-acoustic-impedance layer is made of at least one material selected from the group consisting of W, LiTaO3, Al2O3, AlN, LiNbO3, SiN, and ZnO.
Dependencies are inferred from the claim text.