An acoustic wave device is disclosed. The acoustic wave device can include a first multiplexer that has a first portion and a second portion. The acoustic wave device can include a second multiplexer that has a third portion and a fourth portion. The first portion and the third portion are formed in a first die. The second portion and the fourth portion are formed in a second die that has a different physical structure from the first die.

A multiplexer is disclosed. The multiplexer can include a multilayer piezoelectric substrate surface acoustic wave device that includes at least a portion of a transmission filter. The multiplexer can include a temperature compensated surface acoustic wave device that includes at least a portion of a reception filter. The reception filter is electrically connected to the transmission filter.

An acoustic wave device uses a longitudinal acoustic wave, and includes a piezoelectric layer including first and second principal surfaces opposite to each other, an IDT electrode directly or indirectly on the first principal surface, and a high acoustic velocity member directly or indirectly on the second principal surface and including a 4H-type or 6H-type crystal polytype silicon carbide.

A method of manufacturing an acoustic wave device includes forming a multilayer piezoelectric substrate by forming a piezoelectric layer and forming a support substrate below the piezoelectric layer. The method also includes forming an interdigital transducer electrode including forming a first layer disposed over the piezoelectric layer, forming a second layer disposed over the first layer, the second layer being of a less dense material than the first layer, forming a third layer disposed over the second layer. The method also includes etching the third layer to form a pair of strips extending over one or more fingers of the interdigital transducer electrode and having a density that suppresses a transverse mode of the acoustic wave device.

Acoustic wave device is disclosed. the acoustic wave device can include a piezoelectric layer and an interdigital transducer electrode over the piezoelectric layer. The interdigital transducer electrode has a non-zero tilt angle. The non-zero tilt angle can between 5° to 15°. A thickness of the interdigital transducer electrode is at least 40% of a thickness of the piezoelectric layer, 400 nm, or 0.08λ where λ is the wavelength generated by the acoustic wave device.

An acoustic wave device is disclosed. The acoustic wave device can include a multilayer piezoelectric substrate and an interdigital transducer electrode over the multilayer piezoelectric substrate. The interdigital transducer electrode includes a first layer and a second layer over the first layer. The interdigital transducer electrode has a tilt angle of at least 12 degrees. The acoustic wave device being configured to generate a surface acoustic wave having a wavelength L.

An acoustic wave resonator is disclosed. The acoustic wave resonator can include a plurality of interdigital transducer electrodes and a multilayer piezoelectric substrate (MPS) adjacent the plurality of interdigital transducer electrodes. The MPS includes a first substrate layer of a piezoelectric material, and a second substrate layer of silicon that is bonded to the first layer. The silicon has a cut direction and/or acoustic wave propagation direction that is different from those of a silicon substrate. The silicon substrate has a cut direction and a propagation direction property defined by the silicon cut angle of {100} and the propagation direction <110>.

An acoustic wave device is disclosed. The acoustic waved device can be a shear horizontal mode surface acoustic wave device. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode over the piezoelectric layer, and a temperature compensation layer over the interdigital transducer electrode. The piezoelectric layer can be a lithium niobate layer with a cut angle in a range of −20° YX to 25° YX. The interdigital transducer electrode including a first layer and a second layer. The first layer affects acoustic properties of the acoustic wave device and the second layer affects electrical properties of the acoustic wave device. The second layer is positioned between the piezoelectric layer and the first layer such that a frequency response of the acoustic wave device includes a Rayleigh mode response at a frequency higher than a shear horizontal mode response.

An acoustic wave device is disclosed. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode over the piezoelectric layer, a temperature compensation layer over the interdigital transducer electrode, and a dielectric layer positioned partially between the piezoelectric layer and the interdigital transducer electrode. The dielectric layer is positioned in an area under a first portion of the interdigital transducer electrode. An area under a second portion different from the first portion is free from the dielectric layer.

An acoustic wave device is disclosed. The acoustic wave device can include a piezoelectric layer, an interdigital transducer electrode over the piezoelectric layer, a temperature compensation layer over the interdigital transducer electrode, and a dielectric layer positioned partially between the piezoelectric layer and the interdigital transducer electrode. The interdigital transducer electrode includes an active region that has a center region and an edge region, a bus bar, and a gap region between the active region and the bus bar. At least a portion of the center region is in direct contact with the piezoelectric layer.