A semiconductor device is provided. The semiconductor device incudes: a first sub-semiconductor structure including a dielectric layer; and a second sub-semiconductor structure, at least including a carrier substrate, and being bonded to the first sub-semiconductor structure. The first sub-semiconductor structure or the second sub-semiconductor structure includes a charge accumulation preventing layer, and the charge accumulation preventing layer is disposed between the carrier substrate and the dielectric layer, and is configured to avoid an undesired conductive channel from being generated due to charge accumulation on a surface of the carrier substrate.

A bulk acoustic resonator comprises a membrane including a piezoelectric film having multiple layers of piezoelectric material. At least one of the multiple layers of piezoelectric material has a different dopant concentration than another of the multiple layers of piezoelectric material.

An acoustic wave device is disclosed. The acoustic wave deice can include a membrane structure and a support substrate. The membrane structure includes a piezoelectric layer, an interdigital transducer electrode arranged on the piezoelectric layer, and a thermally conductive layer arranged at least partially in contact with the piezoelectric layer. The support substrate is connected to the membrane structure and configured such that a cavity is provided next to the membrane structure. The acoustic wave device can laterally excite a bulk acoustic wave.

A bulk acoustic resonator having a heat dissipation structure, and a fabrication process are provided according to the present application. The bulk acoustic resonator includes a substrate, a metal heat dissipation layer formed on the base substrate and provided with an insulating layer on the surface thereof, and a resonance functional layer formed on the insulating layer, where the metal heat dissipation layer and the insulating layer together define a cavity on the substrate, a side wall of the cavity is formed by the insulating layer, and a bottom electrode layer in the resonance function layer covers the cavity.

A film bulk acoustic wave resonator (FBAR) is disclosed with recessed and raised frame portions in the piezoelectric film. The FBAR can include a substrate, the piezoelectric film supported to oscillate in a direction opposite to a main surface of the substrate, and a pair of top and bottom electrodes formed respectively on top and bottom surfaces of the film. The recessed frame portion and the raised frame portion can be formed in the film to extend adjacent to each other along a periphery of an active region of the film oscillating during an operation of the film on a top surface of the top electrode.

An acoustic wave device includes a support substrate, a piezoelectric layer on the support substrate, a functional electrode on the piezoelectric layer, first and second electrode films on the piezoelectric layer, facing each other, and having different electric potentials from each other, and a dielectric film between at least one of at least a portion of the first electrode film and the piezoelectric layer and at least a portion of the second electrode film and the piezoelectric layer.

An acoustic wave device includes a support substrate, a piezoelectric layer on the support substrate, a functional electrode on the piezoelectric layer, and first and second electrode films on the piezoelectric layer, facing each other, and having different electric potentials from each other. When a region between the first and second electrode films in a plan view is an inter-electrode film region, and a region overlapping with the first electrode film or the second electrode film in a plan view is an electrode film underlying region, a thickness of the piezoelectric layer in at least a portion of the inter-electrode film region is smaller than a thickness of the piezoelectric layer in the electrode film underlying region.

A filter includes a piezoelectric film, an acoustic wave resonator including a functional electrode on the piezoelectric film, a capacitor connected in parallel to the acoustic wave resonator, and a resonator electrically connected to the acoustic wave resonator. The functional electrode includes first and second busbars facing each other and first and second electrodes respectively connected to the first and second busbars. The filter further includes a connection electrode on the piezoelectric film and electrically connecting the capacitor and the second busbar to each other. The capacitor includes the first busbar, an insulation film on the first busbar, and a capacitance electrode on the insulation film and that is electrically insulated from the first busbar.

An acoustic wave device includes a support substrate, a piezoelectric layer on the support substrate, functional electrodes on the piezoelectric layer, and first and second electrode films positioned on the piezoelectric layer to face each other and having different potentials from each other. A thickness of the piezoelectric layer in at least a portion of a first region overlapping the first electrode film in plan view is different from a thickness of the piezoelectric layer in at least a portion of a second region not overlapping the first electrode film in plan view.

A thin film bulk acoustic resonator and a method for manufacturing the same. The thin film bulk acoustic resonator comprises a bottom electrode layer, a piezoelectric layer, and a top electrode layer, which are disposed on a substrate in which an acoustic reflection structure is located, where a portion which is of the piezoelectric layer and corresponds to a boundary of the acoustic reflection structure is depolarized to form a depolarized portion. The method comprises providing a bottom electrode layer on a substrate to cover an acoustic reflection structure which is formed or to be formed on the substrate; providing a piezoelectric layer on the bottom electrode layer; depolarizing a portion, which is of the piezoelectric layer and corresponds to a boundary of the acoustic reflection structure, to form a depolarized portion; and providing a top electrode layer on the piezoelectric layer.