Aspects of the disclosure relate to an electroacoustic device that includes a piezoelectric material and an electrode structure. The electrode structure includes a first busbar and a second busbar. The electrode structure further includes a first conductive structure connected to the first busbar and a second conductive structure connected to the second busbar. The first conductive structure and the second conductive structure is disposed between the first busbar and the second busbar. The first conductive structure and the second conductive structure each include a plurality of conductive segments separated from each other and extending towards one of the first busbar or the second busbar. The electrode structure further includes electrode fingers arranged in an interdigitated manner and each connected to either the first conductive structure or the second conductive structure. The electrode fingers have a pitch that is different than a pitch of the plurality of conductive segments.

A filter device that reduces spurious emissions generated in a frequency band 1.2 to 1.4 times greater than a center frequency of a passband of a filter. In one example the filter device includes a first filter connected between a common contact and a first signal contact and having a first passband, and a second filter connected between the common contact and a second signal contact and having a second passband with a center frequency in a range of 1.2 to 1.4 times greater than a center frequency of the first passband. The first filter includes a SAW filter formed on a piezoelectric substrate, a SAW resonator formed on the piezoelectric substrate and connected in series between the common contact and the SAW filter, and a dielectric film covering the SAW filter and SAW resonator, the dielectric film having a reduced thickness in a region corresponding to the SAW resonator.

A surface acoustic wave (SAW) resonator includes a piezoelectric layer disposed over a substrate, and a plurality of electrodes disposed over the first surface of the piezoelectric layer. A layer is disposed between the substrate and the piezoelectric layer. A surface of the layer has a smoothness sufficient to foster atomic bonding between layer and the piezoelectric layer. A plurality of features provided on a surface of the substrate reflects acoustic waves and reduce the incidence of spurious modes in the piezoelectric layer.

An acoustic wave element comprising a lithium tantalate substrate having the Euler angles (, , ), a first component satisfying 1050; and an electrode disposed on the lithium tantalate substrate and configured to excite a main acoustic wave of wavelength , the electrode having a density M satisfying MTi where Ti represents a density of titanium (Ti), and a thickness hM of the electrode satisfies 0.141exp(0.075M)hM0.134 Embodiments of the present disclosure minimize a thickness of the electrode and suppress a spurious Rayleigh wave signal.

The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.

An elastic wave device includes a piezoelectric substrate, a first elastic wave element on the piezoelectric substrate and including at least one first interdigital transducer electrode and a first reflector in an area of the first interdigital transducer electrode at one side in a propagation direction of elastic waves, and a second elastic wave element on the piezoelectric substrate and including at least one second interdigital transducer electrode and a second reflector in an area of the second interdigital transducer electrode at one side in the propagation direction of elastic waves. The first and second reflectors are disposed side by side in the propagation direction. A reflection member, between the first and second reflectors, reflects elastic waves in at least a direction different from the propagation direction.

A SAW filter includes a substrate, an upper bus bar arranged on the substrate, a lower bus bar arranged on the substrate so as to face the upper bus bar, a first finger IDT arranged so as to be connected to the upper bus bar at one end, a second finger IDT arranged so as to be connected to the lower bus bar at one end, a passivation part formed on the first finger IDT and the second finger IDT, a first metal part formed on the passivation part and including all area of the upper bus bar and a partial area of the first finger IDT, and a second metal part formed on the passivation part and including all area of the lower bus bar and a partial area of the second finger IDT.

The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.

An elastic wave filter device includes a piezoelectric film, a high acoustic velocity support substrate in which an acoustic velocity of a propagating bulk wave is larger than an acoustic velocity of a main mode elastic wave propagating in the piezoelectric film, and IDT electrodes in contact with the piezoelectric film. A serial arm resonator and a parallel arm resonator are defined by the IDT electrodes such that, a direction in which tips of first and second electrode fingers are connected defines a tilt angle with respect to a propagation direction of elastic waves excited by the IDT electrodes. A tilt angle of the serial arm resonator is different from a tilt angle of the parallel arm resonator.

The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.