Piezoelectric Resonator and Piezoelectric Thin-Film Filter
AssigneeMurata Manufacturing Co., Ltd.
InventorsYuka Mori, Hideki Kawamura
Life of this patent
Estimating the term…
Abstract
A piezoelectric resonator and a piezoelectric thin-film filter including the piezoelectric resonator. The piezoelectric resonator includes a piezoelectric layer disposed between a pair of conductive layers to form a vibrating region. Outer edges of the vibrating region each have a waveform. The vibrating region includes a peripheral portion extending along the outer edges of the planar shape and having a relatively small thickness; and a central portion extending inside the peripheral portion and having a relatively large thickness. The piezoelectric resonator is thus capable of suppressing long-wavelength spurious modes and short-wavelength spurious modes.
Claims20
A piezoelectric resonator comprising:
- a substrate;
- a pair of conductive layers disposed on the substrate;
- and
- a piezoelectric layer disposed between the pair of conductive layers,
- wherein the piezoelectric layer disposed between the pair of conductive layers is acoustically isolated from the substrate to form a vibrating region,
- the vibrating region when viewed in a thickness direction of the pair of conductive layers and the piezoelectric layer has a substantial polygon shape, the sides of which are not parallel to each other, and
- the vibrating region includes a peripheral portion extending along outer edges of the substantial polygon shape and a central portion inside the peripheral portion, the central portion having a larger thickness than the peripheral portion.
Dependencies are inferred from the claim text.