A piezoelectric film on a substrate is provided comprising an aluminum nitride (AlN) layer, and a Al.sub.1-x(J).sub.xN compound layer comprising a graded section with a lower (J) composition, x, adjacent to the AlN layer and a higher (J) composition, x, located away from the AlN layer, the said (J) being a singular element or a binary compound. A method for forming such a piezoelectric film is also provided. A surface acoustic wave resonator comprising such a piezoelectric film, a surface acoustic wave filter comprising such a piezoelectric film, a bulk acoustic wave resonator comprising such a piezoelectric film, and a bulk acoustic wave filter comprising such a piezoelectric film are also provided.

An acoustic resonator has a substrate having a surface and a single-crystal piezoelectric plate, with a portion of the piezoelectric plate forming a diaphragm that spans a cavity in the substrate. An interdigital transducer (IDT) is formed on a surface of the single-crystal piezoelectric plate such that interleaved fingers of the IDT are disposed on the diaphragm. The ends of IDT interleaved fingers or inner surfaces of the opposing busbars have a curved shape. In some cases, gaps between ends of the interleaved fingers and opposing busbars have one of circular gap shapes or parabolic gap shapes. The cavity may be formed in an intermediate layer of the substrate.

An acoustic wave device includes: a piezoelectric substrate; electrodes sandwiching the piezoelectric substrate and exciting a thickness shear vibration in the piezoelectric substrate; and an edge region that is a region surrounding a center region of a resonance region, wherein a first region of the edge region is located on both sides of the center region in a first direction substantially parallel to a displacement direction of a thickness shear vibration, a second region of the edge region is located on both sides of the center region in a second direction substantially perpendicular to the first direction, a width of the second region is different from a width of the first region, and acoustic velocities of acoustic waves in the piezoelectric substrate in the first and second regions are less than that in the piezoelectric substrate in the center region.

A hybrid resonator includes an acoustic wave resonator (AWR) having a piezoelectric material; a first electrical contact, electrically conductively connected to the piezoelectric material; and a second electrical contact, electrically conductively connected to the piezoelectric material. The hybrid resonator further includes a first resonant circuit, electrically conductively connected in series or parallel to the acoustic wave resonator via at least one of the first electrical contact and the second electrical contact. The resonant circuit includes a first inductor, and a first capacitor; wherein, if the first resonant circuit is electrically conductively connected to the acoustic wave resonator in series, the first inductor and the first capacitor are electrically conductively connected to one another in parallel, and if the first resonant circuit is electrically conductively connected to the acoustic wave resonator in parallel, the first inductor and the first capacitor are electrically conductively connected to one another in series.

A film bulk acoustic wave resonator comprising a piezoelectric film having a central region defining a main active domain in which a main acoustic wave is generated during operation, an upper electrode disposed on a top surface of the piezoelectric film, a lower electrode disposed on a lower surface of the piezoelectric film, a dielectric material layer disposed on a lower surface of the lower electrode, and lower recessed frame regions disposed laterally on opposite sides of the central region, the lower recessed frame regions defined by regions of one of the dielectric material or of the lower electrode having a lesser thickness than the thickness of the one of the dielectric material layer or of the lower electrode in the central region.

An acoustic resonator device is formed using a wafer-to-wafer bonding process by etching recesses into a first surface of a piezoelectric substrate, a depth of the recesses greater than a target piezoelectric membrane thickness; then wafer-to-wafer bonding the first surface of the piezoelectric substrate to a handle wafer using a releasable bonding method. The piezoelectric substrate is then thinned to the target piezoelectric membrane thickness to form a piezoelectric plate and at least one conductor pattern is formed on the thinned piezoelectric plate. The side of the thinned piezoelectric plate having the conductor pattern is bonded to a carrier wafer using a metal-to-metal wafer bonding process and the handle wafer is removed.

Provided are a resonator, a method of manufacturing the resonator, and a strain sensor and a sensor array including the resonator. The resonator is provided to extend in a lengthwise direction from a support. The resonator includes a single crystal material and is provided to extend in a crystal orientation that satisfies at least one from among a Young's modulus and a Poisson's ratio, from among crystal orientations of the single crystal material.

A bulk acoustic wave (BAW) device is provided comprising a first electrode, a second electrode, a piezoelectric layer positioned between the first electrode and the second electrode, and a raised frame structure outside of a middle area of an active domain of the BAW device, the raised frame structure comprising one or more raised frame layer(s). At least one of the raised frame layer(s) comprises a tapered portion tapering in a direction towards the middle area of the active domain. A packaged module comprising such a BAW device is also provided. A wireless mobile device comprising such a packaged module is also provided.

A thin film piezoelectric acoustic wave resonator and a manufacturing method therefor, and a filter. The film piezoelectric acoustic wave resonator includes: a first base, a first electrode, a piezoelectric plate body, a second electrode and an isolation cavity, wherein the first electrode, the piezoelectric plate body and the second electrode are arranged on a first surface of the first base and are stacked sequentially from top to bottom; the first electrode, the piezoelectric plate body and the second electrode are provided with an overlapping region in a direction perpendicular to the surface of the piezoelectric plate body; in the overlapping region, a gap is formed between the piezoelectric plate body and the first electrode; the isolation cavity surrounds the periphery of the piezoelectric plate body; and the gap communicates with the isolation cavity.

A thin film piezoelectric acoustic wave resonator and a manufacturing method therefor, and a filter. The film piezoelectric acoustic wave resonator includes: a first base, a first electrode, a piezoelectric plate body, a second electrode and an isolation cavity, wherein the first electrode, the piezoelectric plate body and the second electrode are arranged on a first surface of the first base and are stacked sequentially from top to bottom; the first electrode, the piezoelectric plate body and the second electrode are provided with an overlapping region in a direction perpendicular to the surface of the piezoelectric plate body; in the overlapping region, a gap is formed between the piezoelectric plate body and the first electrode; the isolation cavity surrounds the periphery of the piezoelectric plate body; and the gap communicates with the isolation cavity.