Abstract: Aspects of this disclosure relate to a filter that includes an acoustic wave device with a multi-layer substrate with heat dissipation. The multi-layer substrate includes a support substrate (e.g., a quartz substrate), a piezoelectric layer, an interdigital transducer electrode on the piezoelectric layer, and a thermally conductive layer configured to dissipate heat associated with the acoustic wave device. The thermally conductive layer is disposed between the support substrate and the piezoelectric layer. The thermally conductive layer has a thickness that is greater than 10 nanometers and less than a thickness of the piezoelectric layer.

Abstract: Aspects of this disclosure relate to a surface acoustic wave device. The surface acoustic wave device includes a piezoelectric layer and an interdigital transducer. The interdigital transducer electrode includes a pair of electrodes, each electrode having a bus bar and fingers extending from the bus bar. The interdigital transducer electrode has an interdigital region defined by a portion of the fingers of the electrodes that interdigitate with each other. A dielectric layer is disposed over the interdigital transducer electrode outside the interdigital region and configured to reduce a loss of the surface acoustic wave device.

Abstract: A surface acoustic wave device is disclosed. The surface acoustic wave device can include a first interdigital transducer electrode that is in electrical communication with a first piezoelectric layer and a second interdigital transducer electrode that is in electrical communication with a second piezoelectric layer. The first and second interdigital transducer electrodes are positioned between at least a portion of the first piezoelectric layer and at least a portion of the second piezoelectric layer. The first and second interdigital transducer electrodes are positioned such that the second interdigital transducer electrode is configured to transduce a wave generated by the first interdigital transducer electrode. The first interdigital transducer electrode can be an input interdigital transducer electrode, and the second interdigital transducer electrode can be an output interdigital transducer electrode.

Abstract: An interdigital transducer assembly for a surface acoustic wave device has a pair of busbars with a plurality of interdigitated electrode fingers therebetween. Each electrode finger begins its length at one of the busbars and has an electrode tip that extends towards but does not reach the other busbar. A pair of mass loading strips are each disposed above a respective set of the electrode tips and having a plurality of mass loading stubs arranged along the length of the mass loading strip, with the stubs each aligned with a corresponding electrode tip.

Abstract: A packaged acoustic wave filter component can include an acoustic wave device including a first piezoelectric layer and an interdigital transducer electrode on the first piezoelectric layer. A support layer may be included over the acoustic wave device, and the packaged hybrid filter component can also include a bulk acoustic wave resonator over the support layer. A cap layer may extend over and encapsulate the bulk acoustic wave resonator. One or more external vias may extend through the support layer and the underlying layers of the acoustic wave device to provide electrical communication with the packaged bulk acoustic wave generator.

Abstract: An acoustic wave device is disclosed. The acoustic wave device includes a support layer, a ceramic layer positioned over the support layer, a piezoelectric layer positioned over the ceramic layer, and an interdigital transducer electrode positioned over the piezoelectric layer. The support layer has a higher thermal conductivity than the ceramic layer. The ceramic layer can be a polycrystalline spinel layer. The acoustic wave device can be a surface acoustic wave device configured to generate a surface acoustic wave.

Abstract: A surface acoustic wave device is disclosed. The surface acoustic wave device can include a ceramic substrate, a piezoelectric layer over the ceramic substrate, and an interdigital transducer electrode over the piezoelectric layer. The ceramic substrate can be a polycrystalline spinel substrate. The surface acoustic wave device can also include a temperature compensating layer over the interdigital transducer electrode.

Abstract: A laterally excited bulk acoustic wave device is disclosed. The laterally excited bulk acoustic wave device can include a first solid acoustic mirror, a second solid acoustic mirror, a piezoelectric layer that is positioned between the first solid acoustic mirror and the second solid acoustic mirror, an interdigital transducer electrode on the piezoelectric layer, and a support substrate arranged to dissipate heat associated with the bulk acoustic wave. The interdigital transducer electrode is arranged to laterally excite a bulk acoustic wave. The first solid acoustic mirror and the second solid acoustic mirror are arranged to confine acoustic energy of the bulk acoustic wave. The first solid acoustic mirror is positioned on the support substrate.

Abstract: An acoustic wave device comprising a piezoelectric substrate with an interdigital transducer electrode disposed on the piezoelectric substrate and configured to excite an acoustic wave having a wavelength of ?. The device includes a temperature compensating layer disposed on the interdigital transducer electrode and having a dielectric material including a titanium compound.

Abstract: A filter assembly operating at wider passband with an enhanced reflection coefficient is provided herein. In certain embodiments, the filter assembly comprises a first filter configured to allow signals received via an antenna node to pass at a first passband, the first filter including a plurality of resonators connected in series and parallel arms, the plurality of resonators of the first filter including a first type of resonator configured to broaden the first passband, at least a series resonator nearest to the antenna node or a shunt resonator nearest to the antenna node among the plurality of resonators of the first filter being a second type of resonator configured to improve reflection characteristics at a stopband of the first filter, and a second filter configured to allow the signals received via the antenna node to pass at a second passband using the second type of resonators.

Abstract: Aspects of this disclosure relate to a surface acoustic wave resonator having a multi-layer substrate with heat dissipation. The multi-layer substrate includes a support substrate, a piezoelectric layer, and a thermally conductive layer configured to dissipate heat associated with the surface acoustic wave resonator. The thermally conductive layer is disposed between the support substrate and the piezoelectric layer. Related surface acoustic wave filters, radio frequency modules, and wireless communication devices are also disclosed.

Abstract: Aspects of this disclosure relate to a surface acoustic wave filter with an acoustic velocity adjustment structure. The surface acoustic wave filter can include a first interdigital transducer electrode disposed on a piezoelectric layer, an acoustic reflector disposed on the piezoelectric layer, and a second interdigital transducer electrode disposed on the piezoelectric layer. The second interdigital transducer electrode is longitudinally coupled to the first interdigital transducer electrode and positioned between the first interdigital transducer electrode and the acoustic reflector. The acoustic velocity adjustment structure can be positioned over at least a gap between the first interdigital transducer electrode and the second interdigital transducer electrode.

Abstract: Aspects of this disclosure relate to a surface acoustic wave device. The surface acoustic wave device includes a piezoelectric layer and an interdigital transducer. The interdigital transducer electrode includes a pair of electrodes, each electrode having a bus bar and fingers extending from the bus bar. The interdigital transducer electrode has an interdigital region defined by a portion of the fingers of the electrodes that interdigitate with each other. A dielectric layer is disposed over the interdigital transducer electrode outside the interdigital region and configured to reduce a loss of the surface acoustic wave device.

Abstract: An acoustic wave device is disclosed. The acoustic wave device can include a piezoelectric layer, and an interdigital transducer electrode formed with the piezoelectric layer. The interdigital transducer electrode includes a finger extending from a bus bar. The finger has a first region and a second region between the first region and the bus bar. The finger has a lower side, an upper side opposite the lower side, and a sidewall between the lower side and the upper side. A corner between the upper side and the sidewall is more rounded in the second region than in the first region.

Abstract: An acoustic wave device is disclosed. The acoustic wave device can include a piezoelectric layer, and an interdigital transducer electrode formed with the piezoelectric layer. The interdigital transducer electrode includes a finger extending from a bus bar. The finger has a first region and a second region between the first region and the bus bar. The finger has a lower side and an upper side opposite the lower side. The lower side is closer to the piezoelectric layer than the upper side. Widths of the lower side in the first and second regions are generally the same, and a width of the upper side in the first region is greater than a width of the upper side in the second region.

Abstract: A method of forming an acoustic wave device is disclosed. The method can include providing a piezoelectric layer, forming an interdigital transducer electrode with the piezoelectric layer, and selectively removing at least a portion of the interdigital transducer electrode. The interdigital transducer electrode includes a finger extending from a bus bar. The finger has a first region and a second region between the first region and the bus bar. The finger has a lower side, an upper side opposite the lower side, a sidewall between the lower side and the upper side, and a corner between the upper side and the sidewall. Selectively removing at least a portion of the interdigital transducer electrode includes selectively removing at least a portion of the second region of the finger such that the corner in the second region of the finger has a more rounded corner than the corner in the first region.

Abstract: An acoustic wave device is disclosed. The acoustic wave device includes a support layer, a ceramic layer positioned over the support layer, a piezoelectric layer positioned over the ceramic layer, and an interdigital transducer electrode positioned over the piezoelectric layer. The support layer has a higher thermal conductivity than the ceramic layer. The ceramic layer can be a polycrystalline spinel layer. The acoustic wave device can be a surface acoustic wave device configured to generate a surface acoustic wave.

Abstract: A laterally excited bulk acoustic wave device is disclosed. The laterally excited bulk acoustic wave device can include a support substrate, a solid acoustic mirror on the support substrate, a piezoelectric layer on the solid acoustic mirror, and an interdigital transducer electrode on the piezoelectric layer. The interdigital transducer electrode is arranged to laterally excite a bulk acoustic wave.

Abstract: A surface acoustic wave device is disclosed. The surface acoustic wave device can include a single crystal support layer, an intermediate single crystal layer positioned over the single crystal support layer, a lithium based piezoelectric layer positioned over the intermediate single crystal layer, and an interdigital transducer electrode positioned over the lithium based piezoelectric layer, the surface acoustic wave device configured to generate a surface acoustic wave. The single crystal layer can be a quartz layer, such as a z-propagation quartz layer. A thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the intermediate single crystal layer, and the thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the lithium based piezoelectric layer.

Abstract: Aspects of this disclosure relate to an acoustic wave resonator with hyperbolic mode suppression. The acoustic wave resonator can include a piezoelectric layer, an interdigital transducer electrode, a temperature compensation layer, and a mass loading strip. The mass loading strip can be a conductive strip. The mass loading strip can overlap edge portions of fingers of the interdigital transducer electrode. A layer of the mass loading strip can have a density that is at least as high as a density of a material of the interdigital transducer electrode. The material of the interdigital transducer can impact acoustic properties of the acoustic wave resonator.