Patent ID: 7940145

Claim:
A thin film piezoelectric bulk acoustic wave resonator comprising a resonance part including at least one vibration unit, a supporter that supports the resonance part, and an input/output terminal, wherein each of the at least one vibration unit having a multilayer structure comprising: a piezoelectric thin film; a first metal electrode film; and a second metal electrode film; wherein at least a part of the piezoelectric thin film is interposed between the first and second metal electrode films, wherein the piezoelectric thin film is polarized in a direction perpendicular to a film surface and vibrates in radial extension mode, wherein the supporter is connected onto an insulating substrate at a vibration node of the resonance part, wherein the resonance part comprises at least one connection part and a plurality of vibration units from the at least one vibration unit, wherein all of the plurality of vibration units and the at least one connection part are formed on the insulating substrate as films, wherein at least two of the plurality of vibration units connected to each other via the at least one connection part are symmetrical with respect to a plane, wherein the supporter is configured to hold the resonance part only at a center of the at least one connection part and having a plurality of electrical drawing lines, wherein the at least one connection part has a multilayer structure including a first metal electrode film, a second metal electrode film, and a piezoelectric thin film, wherein an elastic insulating layer is interposed between the at least two of the plurality of vibration units and the at least one connection part, and the insulating substrate, wherein the first metal electrode films of the at least two of the plurality of vibration units are electrically connected in direct current to each other via the at least one connection part, wherein the second metal electrode films of the at least two of the plurality of vibration units are electrically connected in direct, current to each other via the at least one connection part, wherein the piezoelectric thin films of the at least two of the plurality of vibration units are elastically connected to each other via the at least one connection part, wherein the first metal electrode films of the at least two of the plurality of vibration units are electrically connected in direct current to at least one of the plurality of electrical drawing lines via the first metal electrode film of the at least one connection part, wherein the second metal electrode films of the at least two of the plurality of vibration units are electrically connected in direct current to another at least one of the plurality of electrical drawing lines via the second metal electrode film of the at least one connection part, and wherein a width of the at least one connection part is one-fourth or less of a width of the at least two of the plurality vibration units.