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 having a non-zero tilt angle. The non-zero tilt angle can between 5° to 15°. The interdigital transducer electrode is configured to shift stopband of the acoustic wave device and to reduce a slanted stopband.

An acoustic wave device includes a support substrate, a piezoelectric layer provided on the support substrate, at least a pair of comb-shaped electrodes provided on the piezoelectric layer, each of the comb-shaped electrodes including a plurality of electrode fingers, and an insulating layer provided between the support substrate and the piezoelectric layer, the insulating layer having, in at least a part thereof, a plurality of void regions of which extending directions are different from each other when viewed from a thickness direction of the support substrate, a width in the corresponding extending direction of each of the void regions being longer than a width in a direction orthogonal to the corresponding extending direction when viewed from the thickness direction of the support substrate.

Aspects of this disclosure relate to an acoustic wave device that includes high velocity layers on opposing sides of a piezoelectric layer. A low velocity layer can be positioned between the piezoelectric layer and one of the high velocity layers, in which the low velocity layer has a lower acoustic velocity than the high velocity layers. The acoustic wave device can be configured to generate a boundary acoustic wave such that acoustic energy is concentrated at a boundary of the piezoelectric layer and the low velocity layer.

An acoustic wave device comprises a substrate including a piezoelectric material, interdigital transducer (IDT) electrodes disposed on a surface of the substrate, a first dielectric film having a lower surface disposed on the IDT electrodes and the surface of the substrate, first strips formed of a first material having a density greater than a density of the first dielectric film disposed within the first dielectric film over tips of the interdigitated electrode fingers in the edge regions of the IDT electrodes, and second strips formed of a second material having a density greater than the density of the first dielectric film disposed within the first dielectric film in the gap regions of the IDT electrodes, laterally spaced from the first strips in a direction perpendicular to a direction of propagation of a main acoustic wave through the acoustic wave device, and extending only partially over the gap regions.

An acoustic wave device, and an acoustic wave filter and electronics module including the same. The acoustic wave device comprises a first interdigital transducer electrode having a first bus bar and a first plurality of electrode fingers extending from the first bus bar, the first bus bar having a width of 3 μm or less in a direction parallel to the extension of the first plurality of electrode fingers, and a second interdigital transducer electrode having a second bus bar and a second plurality of electrode fingers extending from the second bus bar and interleaved with the first plurality of electrode fingers, the second bus bar having a width of 3 μm or less in a direction parallel to the extension of the second plurality of electrode fingers. The acoustic wave device allows for improvements in power durability when used in an acoustic wave filter, without an increase in size of the acoustic wave filter.

A surface acoustic wave device includes a piezoelectric substrate and a pair of interdigital transducer electrodes. The pair of interdigital transducer electrodes include an alternating region as a region where the electrode fingers connected to one busbar and the electrode fingers connected to the other busbar are alternately provided. When a region on an end portion side of the alternating region and a region including distal end portions of the plurality of electrode fingers is referred to as an edge region, a propagation velocity of a surface acoustic wave in the edge region is slower than a propagation velocity of a surface acoustic wave in the alternating region. A propagation velocity of a surface acoustic wave in a busbar region as a region where the busbar is disposed is faster than the propagation velocity of the surface acoustic wave in the alternating region.

A method for making a composite substrate of a filter includes: processing a base substrate to form a centrally protruding structure having a height that decreases in a radially outward direction from a center of the base substrate to an outer periphery of the base substrate; connecting a first side of the base substrate having the centrally protruding structure to a piezoelectric layer so as to obtain a multilayer substrate; and thinning the piezoelectric layer of the multilayer substrate followed by polishing a surface of the piezoelectric layer.

An elastic wave device includes a piezoelectric thin film, IDT electrodes on the piezoelectric thin film, an insulating layer surrounding the piezoelectric thin film on a primary surface of a support substrate, a spacer layer surrounding the piezoelectric thin film in plan view, and a cover on the spacer layer. The spacer layer includes an outer edge and an inner edge closer than the outer edge to the piezoelectric thin film in plan view. The primary surface of the insulating layer closer to the spacer layer includes a sloping region that extends where the insulating layer overlaps the spacer layer in plan view and in which the distance from the first primary surface of the support substrate along the direction perpendicular or substantially perpendicular to the support substrate increases from the outer edge toward the inner edge.

An acoustic wave device includes: a support substrate; a piezoelectric substrate bonded to the support substrate; a first acoustic wave element formed on the piezoelectric substrate; a frame formed on the support substrate to surround the first acoustic wave element; and a substrate formed on the frame so that a cavity to which the first acoustic wave element is exposed is formed above the piezoelectric substrate, wherein a difference in linear expansion coefficient between the support substrate and the substrate in a first direction in a surface direction of the piezoelectric substrate is less than a difference in linear expansion coefficient between the support substrate and the piezoelectric substrate in the first direction, and the piezoelectric substrate remains in a region where the first acoustic wave element is formed and is removed in a region where the frame is formed.

A surface acoustic wave device includes a substrate that has a top surface and that contains a plurality of protrusions protruding from the top surface and spaced apart from each other, an intermediate layer disposed on the substrate so as to fill a recess formed among the protrusions, a piezoelectric layer disposed on the intermediate layer opposite to the substrate, and an electrode layer disposed on the piezoelectric layer opposite to the intermediate layer.