An RF diplexer circuit device using modified lattice, lattice, and ladder circuit topologies. The diplexer can include a pair of filter circuits, each with a plurality of series resonator devices and shunt resonator devices. In the ladder topology, the series resonator devices are connected in series while shunt resonator devices are coupled in parallel to the nodes between the resonator devices. In the lattice topology, a top and a bottom serial configurations each includes a plurality of series resonator devices, and 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. A multiplexing device or inductor device can be configured to select between the signals coming through the first and second filter circuits.

A resonator, a resonator assembly, a filter, an electronic device, a method for fabricating the resonator, and a packaging structure are provided. The bulk acoustic resonator includes a substrate, a first electrode, a second electrode, an acoustic reflection structure between the first electrode and the substrate, and a piezoelectric layer arranged between the second electrode and the first electrode. In a direction perpendicular to the substrate, an overlapping region of the acoustic reflection structure, the first electrode, the piezoelectric layer and the second electrode is an active region that is annular. A distance from a point A on an inner edge of the active region to a center of the resonator is D, and a shortest distance from A to an outer edge of the active region is W, where 0.1W/D10. The heat dissipation rate of the resonator can be improved by modifying W.

An acoustic resonator is fabricated with a substrate having a substrate top surface and a piezoelectric plate having plate front and plate back surfaces. An acoustic Bragg reflector is sandwiched between the substrate top surface and the plate back surface. The reflector has a cavity with a top surface perimeter, and the acoustic Bragg reflector is configured to reflect shear acoustic waves at a resonance frequency of the acoustic resonator. The back surface is mounted on the cavity top surface perimeter except for a portion of the plate forming a diaphragm that spans the cavity. An interdigital transducer (IDT) is formed on the plate front surface such that interleaved fingers of the IDT are disposed on the diaphragm. Two or more layers of the acoustic Bragg reflector form pedestals that support the back surface of the plate opposite some or all interleaved fingers of the IDT.

A method for transferring a piezoelectric layer onto a support substrate comprises:providing a donor substrate including a heterostructure comprising a piezoelectric substrate bonded to a handling substrate, and a polymerized adhesive layer at the interface between the piezoelectric substrate and the handling substrate,forming a weakened zone in the piezoelectric substrate so as to delimit the piezoelectric layer to be transferred,providing the support substrate,forming a dielectric layer on a main face of the support substrate and/or of the piezoelectric substrate,bonding the donor substrate to the support substrate, the dielectric layer being at the bonding interface, and-fracturing and separating the donor substrate along the weakened zone at a temperature below or equal to 300 C.

A bulk acoustic wave resonator and a preparation method thereof, the bulk acoustic wave resonator includes a first electrode and a second electrode, and a piezoelectric film between the first and second electrodes, the piezoelectric film includes n layers of polarized piezoelectric films, and the polarities of any two adjacent layers of the polarized piezoelectric films are opposite. The acoustic mirror is disposed between the substrate and the first electrode, by preparing the polarized piezoelectric films with opposite polarities in layers, polarity inversion is achieved. The bulk acoustic wave resonator of the present disclosure can reduce the requirements for the piezoelectric film materials and increase the resonant frequency under the condition of not reducing the total thickness of the piezoelectric film or introducing a transition electrode. The process is simplified, the acoustic wave loss is reduced, and the quality factor is improved.

Embodiments of a Bulk Acoustic Wave (BAW) resonator in which an outer region of the BAW resonator is engineered in such a manner that lateral leakage of mechanical energy from an active region of the BAW resonator is reduced, and methods of fabrication thereof, are disclosed. In some embodiments, a BAW resonator includes a piezoelectric layer, a first electrode on a first surface of the piezoelectric layer, a second electrode on a second surface of the piezoelectric layer opposite the first electrode, and a passivation layer on a surface of the second electrode opposite the piezoelectric layer, the passivation layer having a thickness (T.sub.PA). The BAW resonator also includes a material on the second surface of the piezoelectric layer adjacent to the second electrode in an outer region of the BAW resonator. The additional material has a thickness that is n times the thickness (T.sub.PA) of the passivation layer.

Embodiments of a Bulk Acoustic Wave (BAW) resonator having a high quality factor (Q) and methods of fabrication thereof are disclosed. In some embodiments, a BAW resonator includes a piezoelectric layer, a first electrode on a first surface of the piezoelectric layer, and a second multi-layer electrode on a second surface of the piezoelectric layer opposite the first electrode on the first surface of the piezoelectric layer. In addition, the BAW resonator includes a Border (BO) ring positioned within the second multi-layer electrode around a periphery of an active region of the BAW resonator. The BO ring is either at a position within the second multi-layer electrode between two adjacent layers of the second multi-layer electrode or at a position within the second multi-layer electrode that is adjacent to the piezoelectric layer. In this manner, the quality factor (Q) of the BAW resonator is improved.

A configurable single crystal acoustic resonator (SCAR) device integrated circuit. The circuit comprises a plurality of SCAR devices numbered from 1 through N, where N is an integer of 2 and greater. Each of the SCAR device has a thickness of single crystal piezo material formed overlying a surface region of a substrate member. The single crystal piezo material is characterized by a dislocation density of less than 10.sup.12 defects/cm.sup.2.

An RF integrated circuit device can includes a substrate and a High Electron Mobility Transistor (HEMT) device on the substrate including a ScAlN layer configured to provide a buffer layer of the HEMT device to confine formation of a 2DEG channel region of the HEMT device. An RF piezoelectric resonator device can be on the substrate including the ScAlN layer sandwiched between a top electrode and a bottom electrode of the RF piezoelectric resonator device to provide a piezoelectric resonator for the RF piezoelectric resonator device.

A method of manufacturing an integrated circuit. This method includes forming an epitaxial material comprising single crystal piezo material overlying a surface region of a substrate to a desired thickness and forming a trench region to form an exposed portion of the surface region through a pattern provided in the epitaxial material. Also, the method includes forming a topside landing pad metal and a first electrode member overlying a portion of the epitaxial material and a second electrode member overlying the topside landing pad metal. Furthermore, the method can include processing the backside of the substrate to form a backside trench region exposing a backside of the epitaxial material and the landing pad metal and forming a backside resonator metal material overlying the backside of the epitaxial material to couple to the second electrode member overlying the topside landing pad metal.