An acoustic wave device includes a substrate, as well as a first electrode layer, a piezoelectric layer and a second electrode layer which are sequentially arranged on the substrate. The device further includes a protective layer. The protective layer is at least arranged at a first position above the surface, far away from the substrate, of the second electrode layer. The first position is a position, corresponding to a first overlapping region, above the second electrode layer. The first overlapping region, where an active area of the acoustic wave device is located, is at least a part of a region where the first electrode layer, the second electrode layer and the piezoelectric layer are overlapped. A fabrication method for an acoustic wave device is also provided.

Multiplexers are disclosed. A multiplexer can include a first filter and a second filter that are coupled to a common node. The second filter can include a first type of acoustic wave resonators (e.g., bulk acoustic wave resonators) and a series acoustic wave resonator of a second type (e.g., a surface acoustic wave resonator) that is coupled between the acoustic wave resonators of the first type and the common node. The first filter can provide a single-ended radio frequency signal. In certain embodiments, the first filter can be a receive filter and the second filter can be a transmit filter.

A semiconductor package includes a main substrate, a resonator device disposed above the main substrate, a wiring portion connected to the resonator device, an electrical connection structure connected to the wiring portion and the main substrate, an encapsulant encapsulating the resonator device and the electrical connection structure, and a heat dissipation member bonded to and mounted on the resonator device. A cavity is provided in the resonator device, and is formed between the resonance portion and a resonator device substrate provided in the resonator device.

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 assembly and a filter are disclosed. The acoustic resonator assembly includes at least two acoustic resonators vertically connected to each other. The acoustic resonator includes: an acoustic mirror, a bottom electrode layer, a piezoelectric layer, and a top electrode layer that are arranged on a substrate. An active area of the acoustic resonator is defined by an overlapping area of the acoustic mirror, the bottom electrode layer, the piezoelectric layer, and the top electrode layer. The acoustic resonator further includes a support layer arranged on the substrate or the piezoelectric layer on a periphery of a projection of the acoustic mirror on the substrate. The at least two acoustic resonators are vertically connected to each other through the support layer. The filter significantly reduces the volume and the area of a device, improves design freedom and reduces design difficulty, enhances product performance and greatly reduces costs.

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. Patterned electrodes are deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the electrodes and a planarized support layer is deposited over the sacrificial layer. The device can include a dielectric protection layer (DPL) that protects the piezoelectric layer from etching processes that can produce rough surfaces and reduces parasitic capacitance around the perimeter of the resonator when the DPL’s dielectric constant is lower than that of the piezoelectric layer. The DPL can be configured between the top electrode and the piezoelectric layer, between the bottom electrode and the piezoelectric layer, or both.

Bulk acoustic wave resonators of two or more different filters can be on a common die. The two filters can be included in a multiplexer, such as a duplexer, or implemented as standalone filters. With bulk acoustic wave resonators of two or more filters on the same die, the filters can be implemented in less physical space compared to implementing the same filters of different die. Related methods, radio frequency systems, radio frequency modules, and wireless communication devices are also disclosed.

A vibrator device has the vibrator element, a support substrate supporting the vibrator element, and a plurality of interconnections disposed on the support substrate. The support substrate includes an element mounting base, a supporting base, a frame located between the element mounting base and the supporting base, inner beams for coupling the element mounting base and the frame to each other, and outer beams for coupling the frame and the supporting base to each other. The plurality of interconnections include a drive signal interconnection and a detection signal interconnection laid around to the element mounting base and the supporting base, and the drive signal interconnection and the detection signal interconnection are laid around to the element mounting base and the frame through the respective inner beams different from each other, and are laid around to the frame and the supporting base through the respective outer beams different from each other.

According to embodiments of the present disclosure, a micro-system comprises a frame, a component attached to and supported by the frame, and an electrically functional micro-device disposed on or in the frame and electrically connected to the component. The component can be exclusively supported by the frame. The frame can comprise the micro-device and can comprise the same materials and layer structure as the component. The component, frame, and micro-device can comprise a piezoelectric material. The component can be an acoustic resonator and the micro-device can be a capacitor.

A method and structure for a transfer process for an acoustic resonator device. In an example, a bulk acoustic wave resonator (BAWR) with an air reflection cavity is formed. A piezoelectric thin film is grown on a crystalline substrate. A first patterned electrode is deposited on the surface of the piezoelectric film. An etched sacrificial layer is deposited over the first electrode and a planarized support layer is deposited over the sacrificial layer, which is then bonded to a substrate wafer. The crystalline substrate is removed and a second patterned electrode is deposited over a second surface of the film. The sacrificial layer is etched to release the air reflection cavity. Also, a cavity can instead be etched into the support layer prior to bonding with the substrate wafer. Alternatively, a reflector structure can be deposited on the first electrode, replacing the cavity.