Methods of forming a shear-mode acoustic wave filter on V-shaped grooves of a [100] crystal orientation Si layer over a substrate and the resulting devices are provided. Embodiments include forming a set of V-shaped grooves in a [100] crystal orientation Si layer over a substrate; and forming a shear-mode acoustic wave filter over the V-shaped grooves, the shear-mode acoustic wave filter including a first metal layer, a thin-film piezoelectric layer, and a second metal layer, wherein the second metal layer is an IDT pattern or a sheet.

A bulk acoustic wave resonator includes a substrate, a lower electrode connection member, a lower electrode, a piezoelectric layer, an upper electrode, an upper electrode connection member, and a dielectric layer in which the lower electrode, the piezoelectric layer, and the upper electrode are embedded. The lower electrode, the piezoelectric layer, and the upper electrode constitute a resonant portion. An extension portion extends away from either the lower electrode or the upper electrode to protrude outwardly from the resonant portion. A capacitor portion is constituted by the extension portion, a portion of the upper electrode connection member disposed above the extension portion, and a portion of the dielectric layer disposed between the extension portion and the portion of the upper electrode connection member disposed above the extension portion.

A micro-resonator includes a first electrode positioned on a piezoelectric plate at a first end of the piezoelectric plate, the first electrode including a first set of fingers and a second electrode positioned on the piezoelectric plate at a second end of the piezoelectric plate. The second electrode including a second set of fingers interdigitated with the first set of fingers with an overlapping distance without touching the first set of fingers, the overlapping distance being less than seven-tenths the length of one of the first set of fingers or the second set of fingers. At least one of the first end or the second end of the piezoelectric plate may define a curved shape.

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.

An acoustic resonator with a reinforcing structure is provided according to the present disclosure. The acoustic resonator includes a substrate and a cavity formed on the substrate, a piezoelectric layer is arranged above the substrate and an opening passing through the piezoelectric layer is formed in a peripheral region of the piezoelectric layer. The reinforcing structure includes a reinforcing layer, part of the reinforcing layer is formed at the edge of the opening with being fitted to the edge, to reinforce a resonant functional layer near the edge of the opening, which can reduce a change in stress of the piezoelectric layer and the lower electrode near the edge of the opening after the cavity is released, so that the piezoelectric layer and the lower electrode do not easily collapse due to stress, thereby ensuring the performance of a device. A method for manufacturing the same is further provided.

Techniques for improving Bulk Acoustic Wave (BAW) mass loading of resonator structures are disclosed, including filters, oscillators and systems that may include such devices. First and second layers of piezoelectric material may be acoustically coupled with one another to have a piezoelectrically excitable resonance mode. The first layer of piezoelectric material may have a first piezoelectric axis orientation, and the second layer of piezoelectric material may have a second piezoelectric axis orientation that substantially opposes the first piezoelectric axis orientation of the first layer of piezoelectric material. An acoustic reflector electrode may include a first pair of top metal electrode layers electrically and acoustically coupled with the first and second layer of piezoelectric material to excite the piezoelectrically excitable resonance mode at a resonant frequency of the BAW resonator. The acoustic reflector may include a mass load layer to facilitate a preselected frequency compensation in the resonant frequency.

A micro-electro-mechanical system (MEMS) device includes a substrate having a cavity and a MEMS structure disposed over the cavity and attached to the substrate. The MEMS structure includes at least one first piezoelectric layer having a first piezoelectric coefficient and two second piezoelectric layers respectively disposed under and above the first piezoelectric layer, where each second piezoelectric layer has a second piezoelectric coefficient higher than the first piezoelectric coefficient. The MEMS structure further includes a first electrode layer and a second electrode layer sandwiching the two second piezoelectric layers.

Techniques for improving Bulk Acoustic Wave (BAW) resonator structures are disclosed, including filters, oscillators and systems that may include such devices. A first layer of piezoelectric material having a piezoelectrically excitable resonance mode may be provided. The first layer of piezoelectric material may have a thickness so that the bulk acoustic wave resonator has a resonant frequency. The first layer of piezoelectric material may include a first pair of sublayers of piezoelectric material, and a first layer of temperature compensating material. A substrate may be provided.

An apparatus and method for making an acoustic filter package where the apparatus includes a base layer; a support layer disposed on the base layer; a piezoelectric structure disposed on the support layer; wherein the piezoelectric structure comprises: a piezoelectric layer; a top electrode on a top surface of the piezoelectric layer; a bottom electrode on a bottom surface of the piezoelectric layer; a contact pad coupled to the bottom electrode that extends through an opening in the piezoelectric layer and is coupled to the bottom electrode or the top electrode; and a corrosion resistant pad disposed on the contact pad; and a capping structure disposed on the piezoelectric structure.

A resonator for testing, a method for manufacturing a resonator for testing, and a method for testing a resonator are provided. The resonator for testing includes: a testing substrate, a testing bottom electrode, a testing piezoelectric layer, a testing top electrode, at least one first testing electrode, and at least one second testing electrode. The first testing electrode is connected to the testing bottom electrode, the second testing electrode is connected to the testing top electrode, a spacing region is arranged between the first testing electrode and the second testing electrode, and a thickness between the testing piezoelectric layer and at least one of the first testing electrode and the second testing electrode is greater than a predetermined thickness to insulate the first testing electrode and the second testing electrode. With the technical solutions according to the present disclosure, the accuracy of the detected resonance frequency adjustment amount caused by the mass loading layer to be tested is improve.