A method of manufacture for an acoustic resonator or filter device. In an example, the present method can include forming metal electrodes with different geometric areas and profile shapes coupled to a piezoelectric layer overlying a substrate. These metal electrodes can also be formed within cavities of the piezoelectric layer or the substrate with varying geometric areas. Combined with specific dimensional ratios and ion implantations, such techniques can increase device performance metrics. In an example, the present method can include forming various types of perimeter structures surrounding the metal electrodes, which can be on top or bottom of the piezoelectric layer. These perimeter structures can use various combinations of modifications to shape, material, and continuity. These perimeter structures can also be combined with sandbar structures, piezoelectric layer cavities, the geometric variations previously discussed to improve device performance metrics.

An acoustic wave device includes a support substrate, a piezoelectric layer, and first and second electrodes. The piezoelectric layer overlaps the support substrate in a first direction. The first and second electrodes extend over at least a first major surface of the piezoelectric layer. The first and second electrodes face each other and are at different potentials. A space between a second major surface of the piezoelectric layer and the support substrate is covered by the piezoelectric layer. The first and second electrodes each include an overlap portion overlapping the space in the first direction and a non-overlap portion not overlapping the space in the first direction. At least part of the support substrate includes an attenuation layer and overlaps a region between the non-overlap portions of the first and second electrodes in plan view. The attenuation layer and the support substrate have different crystallinities.

A bulk acoustic wave (BAW) resonator includes a substrate defining a cavity, a bottom electrode disposed over the substrate and the cavity, a piezoelectric layer disposed on the bottom electrode, and a top electrode disposed on the piezoelectric layer. The piezoelectric layer includes polycrystalline lithium niobate (LN) material or polycrystalline lithium tantalite (LT) material. The BAW resonator may further include an encapsulant layer formed on side and top surfaces of the piezoelectric layer. The encapsulant layer is configured to protect the LN material or the LT material of the piezoelectric layer from a release solvent previously applied to sacrificial material within the cavity in the substrate.

A resonator, a filter and a duplexer, which relate to the technical field of resonators. The resonator includes: a substrate, and a lower electrode layer, a piezoelectric layer and an upper electrode layer, which are sequentially formed on the substrate, wherein an acoustic reflection structure is formed on a surface of the substrate that is close to the lower electrode layer, and an overlapping region of the acoustic reflection structure, the lower electrode layer, the piezoelectric layer and the upper electrode layer along a stacking direction forms a resonant region; and in the resonant region, the surface, which is away from the substrate, of at least one of the lower electrode layer, the piezoelectric layer and the upper electrode layer is etched to form an etched region, the depth of the etched region is less than the thickness of an etched layer, and the area of the etched region is less than the area of the resonant region. By means of controlling an etching area ratio of the resonant region to the etched region, the resonator can obtain a plurality of different resonant frequencies on the same wafer without increasing processes.

The vibrator element includes a base part, a vibrating arm extending from the base part, and a weight provided to the vibrating arm, wherein the weight includes a thick film part, a thin film part thinner in film thickness than the thick film part, and a connection part which is located between the thick film part and the thin film part to connect the thick film part and the thin film part to each other, and which forms a taper shape gradually decreasing in film thickness in a direction from the thick film part side toward the thin film part.

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.

An RF circuit device using modified lattice, lattice, and ladder circuit topologies. The devices can include four resonator devices and four shunt resonator devices. In the ladder topology, the resonator devices are connected in series from an input port to an output port while shunt resonator devices are coupled the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a pair of resonator devices that are coupled to differential input and output ports. A pair of shunt resonators is cross-coupled between each pair of a top serial configuration resonator and a bottom serial configuration resonator. The modified lattice topology adds baluns or inductor devices between top and bottom nodes of the top and bottom serial configurations of the lattice configuration. These topologies may be applied using single crystal or polycrystalline bulk acoustic wave (BAW) resonators.

A piezoelectric vibration member that includes a substrate having a main surface on or in which a piezoelectric vibration member is mounted, a lid having a recess that is open so as to face the main surface and which includes a flange portion that projects outward from an opening edge of the recess, and a bonding layer that bonds the substrate and the lid together so as to hermetically seal the piezoelectric vibrator in a space between the recess and the main surface. The surface roughness of a side surface of the flange portion is greater than the surface roughness of the surface of the recess, and the bonding layer extends from the main surface of the substrate to the side surface of the flange portion.

An acoustic wave filter includes a substrate having voids formed therein; a first resonator disposed on one or more of the voids, and a second resonator disposed on other of the voids. A first trimming layer is provided in the first resonator, and a second trimming layer is provided in the second resonator. The second trimming layer is formed of a material having an etching rate for a given etchant different from that of the first trimming layer.

A piezoelectric component includes a support substrate; a piezoelectric element having both ends fixed to the support substrate, so as to be oscillatable; a pair of terminal electrodes located below the ends of the piezoelectric element, respectively; a pair of capacitance-forming electrodes each having a greater width than the piezoelectric element, extending from the pair of terminal electrodes, respectively, toward a center of the piezoelectric element; and excitation electrodes disposed on a first principal surface and a second principal surface of the piezoelectric element, respectively, the excitation electrodes facing each other so that a facing region in which the excitation electrodes overlap with each other as seen in a transparent plan view is defined therebetween, at least part of a region of the pair of capacitance-forming electrodes which protrudes outside the facing region in a width direction thereof as seen in a plan view, being covered with an insulating film.