Patent ID: 9634226
Date: 2017-04-25
CPC Classifications: H01L,H03H,Y10T

Claim:
1. A Lamb wave device, comprising: a piezoelectric function member that includes a piezoelectric substrate having a first surface and a second surface opposite to the first surface, and IDT electrodes disposed on the first surface, the piezoelectric substrate having a cutout portion therein; and a supporting member having a supporting surface that is bonded to the second surface of the piezoelectric substrate, and a cavity formed therein that faces the IDT electrodes through the piezoelectric substrate, the cavity being formed only in an area that substantially corresponds to the IDT electrodes thereabove, wherein the cutout portion penetrates the piezoelectric substrate to expose a portion of the supporting surface, and wherein an entirety of the second surface of the piezoelectric functional member except areas corresponding to the cavity and the cutout portion is directly bonded to the supporting surface of the supporting member without any wiring pattern interposed between the second surface of the piezoelectric functional member and the supporting surface of the supporting member so that the IDT electrodes excite the Lamb waves in said piezoelectric substrate supported by the supporting member as operational waves and so that a resonance frequency Fr of the Lamb wave device satisfies Fr=V/λ, where V is a phase velocity of the Lamb waves excited in the piezoelectric substrate and λ is a wavelength of the Lamb waves.