An acoustic wave sensor device comprises a quartz material layer surface; arranged along a first axis, a first interdigitated transducer disposed over the planar surface of the quartz material layer, a first reflection structure disposed over the planar surface of the quartz material layer, and a second reflection structure disposed over the planar surface of the quartz material layer; and arranged along a second axis, a second interdigitated transducer disposed over the planar surface of the quartz material layer, a third reflection structure disposed over the planar surface of the quartz material layer, and a fourth reflection structure disposed over the planar surface of the quartz material layer; and wherein the first axis and the second axis are inclined to each other by a finite angle.

An elastic wave element includes a piezoelectric substrate, an IDT electrode including a first comb-shaped electrode and a second comb-shaped electrode, and reflectors. Each of the reflectors includes a first reflective busbar electrode, a second reflective busbar electrode, and reflective electrode fingers. The first comb-shaped electrode includes a first busbar electrode connected to the first reflective busbar electrodes, and first electrode fingers. The second comb-shaped electrode includes a second busbar electrode and second electrode fingers. In in-between areas, in each of which a reflective electrode finger and a first electrode finger adjacent to each other in the elastic-wave propagation direction face each other, connecting electrodes which electrically couple the reflective electrode fingers to the first electrode fingers are provided.

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.

Provided is a joined body including a piezoelectric substrate and a polycrystalline spinel substrate provided on one main surface of the piezoelectric substrate, wherein the polycrystalline spinel substrate has a porosity of 0.005% or more and 0.6% or less.

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.

A guided acoustic wave device includes a substrate, a lithium tantalate layer on the substrate, and a transducer on the lithium tantalate film. The lithium tantalate has a crystalline orientation defined by (YXl), where is between 10 and 37. The inventors discovered that limiting the crystalline orientation of the lithium tantalate in this manner provides significant increases in the electromechanical coupling coefficient of the acoustic wave device, thereby increasing bandwidth and improving performance.

A high-frequency filter including first and second signal terminals, a filter circuit having a passband and a stopband and being connected between the first signal terminal and the second signal terminal, and an additional circuit connected in parallel with the filter circuit between the first signal terminal and the second signal terminal. The filter circuit is configured to provide a first output signal responsive to receipt of an input signal. The additional circuit has an attenuation band within the stopband, and is configured to provide a second output signal responsive to receiving the input signal, the first and second output signals having phase components opposite to each other in the attenuation band.

A high-frequency filter including first and second signal terminals, a filter circuit having a passband and a stopband and being connected between the first signal terminal and the second signal terminal, and an additional circuit connected in parallel with the filter circuit between the first signal terminal and the second signal terminal. The filter circuit is configured to provide a first output signal responsive to receipt of an input signal. The additional circuit has an attenuation band within the stopband, and is configured to provide a second output signal responsive to receiving the input signal, the first and second output signals having phase components opposite to each other in the attenuation band.

A guided acoustic wave device includes a substrate, a lithium tantalate layer on the substrate, and a transducer on the lithium tantalate film. The lithium tantalate has a crystalline orientation defined by (YXl), where is between 10 and 37. The inventors discovered that limiting the crystalline orientation of the lithium tantalate in this manner provides significant increases in the electromechanical coupling coefficient of the acoustic wave device, thereby increasing bandwidth and improving performance.

A receiver includes a quadrature mixer to perform frequency conversion to convert a radio-frequency signal into an I signal and a Q signal that have a 90 phase difference from each other and a surface acoustic wave (SAW) device to perform phase conversion on the I signal and the Q signal that are output from the quadrature mixer. In the SAW device, when represents a phase rotation amount of the I signal, represents a phase rotation amount of the Q signal, and n is an integer, (+90n36035.1)(+90+n360+35.1) or (90+n36035.1)(90+n360+35.1).