A film bulk acoustic resonator (FBAR) and a method of fabricating the FBAR are disclosed. In the method, formation of several mutually overlapped and hence connected sacrificial material layers above and under a resonator sheet facilitates the removal of the sacrificial material layers. Cavities left after the removal overlap at a polygonal area with non-parallel sides. This reduces the likelihood of boundary reflections of transverse parasitic waves causing standing wave resonance in the FBAR, thereby enhancing its performance in parasitic wave crosstalk. Further, according to the invention, the FBAR is enabled to be integrated with CMOS circuitry and hence exhibits higher reliability.

Embodiments of this disclosure relate to acoustic wave filters configured to filter radio frequency signals. An acoustic wave filter includes a first bulk acoustic wave resonator on a substrate, a second bulk acoustic wave resonator on the substrate, a conductor electrically connecting the first bulk acoustic wave resonator in anti-series with the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate. The air gap can reduce parasitic capacitance associated with the conductor. Acoustic wave filters disclosed herein can suppress a second harmonic.

Embodiments of this disclosure relate to bulk acoustic wave resonators on a substrate. The bulk acoustic wave resonators include a first bulk acoustic wave resonator, a second bulk acoustic wave resonator, a conductor electrically connecting the first bulk acoustic wave resonator to the second bulk acoustic wave resonator, and an air gap positioned between the conductor and a surface of the substrate.

An acoustic wave device includes an acoustic wave substrate including a first main surface and a second main surface, IDT electrodes provided on the first main surface, and sealing resin covering at least the second main surface of the acoustic wave substrate. A hollow is provided in a region where the IDT electrodes on the first main surface of the acoustic wave substrate is located. The sealing resin has through-holes each extending from a top surface 13B of the sealing resin to the second main surface of the acoustic wave substrate. The acoustic wave substrate is made of silicon or includes a layer made of silicon.

A piezoelectric oscillation device includes a piezoelectric vibration element, a heating element that heats the piezoelectric vibration element, an electronic component that is electrically connected to the piezoelectric vibration element, a substrate on which the piezoelectric vibrator, the heating element, and the electronic component are mounted, and a base member to which the substrate is attached with a prescribed spacing therebetween via a substrate holding member. The substrate holding member includes a conductive part. The conductive part has a lower thermal conductivity than metal.

A method of making a micro-module structure comprises providing a substrate, the substrate having a substrate surface and comprising a substrate post protruding from the substrate surface. A component is disposed on the substrate post, the component having a component top side and a component bottom side opposite the component top side, the component bottom side disposed on the substrate post. The component extends over at least one edge of the substrate post. One or more component electrodes are disposed on the component.

A method of printing comprises providing a component source wafer comprising components, a transfer device, and a patterned substrate. The patterned substrate comprises substrate posts that extend from a surface of the patterned substrate. Components are picked up from the component source wafer by adhering the components to the transfer device. One or more of the picked-up components are printed to the patterned substrate by disposing each of the one or more picked-up components onto one of the substrate posts, thereby providing one or more printed components in a printed structure.

A method of manufacture and structure for an acoustic resonator device having a hybrid piezoelectric stack with a strained single crystal layer and a thermally-treated polycrystalline layer. The method can include forming a strained single crystal piezoelectric layer overlying the nucleation layer and having a strain condition and piezoelectric layer parameters, wherein the strain condition is modulated by nucleation growth parameters and piezoelectric layer parameters to improve one or more piezoelectric properties of the strained single crystal piezoelectric layer. Further, the method can include forming a polycrystalline piezoelectric layer overlying the strained single crystal piezoelectric layer, and performing a thermal treatment on the polycrystalline piezoelectric layer to form a recrystallized polycrystalline piezoelectric layer. The resulting device with this hybrid piezoelectric stack exhibits improved electromechanical coupling and wide bandwidth performance.

A tunable band pass filter (BPF), including a first transmission line electromagnetically coupled to a second transmission line, wherein a length of at least one of the first transmission and the second transmission line is adjustable, and wherein a frequency of a passband of the BPF is directly related to the length of the adjustable transmission line.

Devices and processes for preparing devices are described for a bulk acoustic wave resonator. A stack includes a first electrode that is coupled to a first side of a piezoelectric layer and a second electrode that is coupled to a second side of the piezoelectric layer. The stack is configured to resonate in response to an electrical signal applied between the first electrode and the second electrode. A cavity frame is coupled to the first electrode and to the substrate. The cavity frame forms a perimeter around a cavity. Optionally, a heat dissipating frame is formed and coupled to the second electrode. The cavity frame and/or the heat dissipating frame improve the thermal stability of the bulk acoustic resonator.