A bonded body includes a supporting substrate, a silicon oxide layer provided on the supporting substrate, and a piezoelectric material substrate provided on the silicon oxide layer and composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate. An average value of a nitrogen concentration of the silicon oxide layer is higher than a nitrogen concentration at an interface between the silicon oxide layer and supporting substrate and higher than a nitrogen concentration at an interface between the silicon oxide layer and piezoelectric material substrate.

A method for making a composite substrate of a filter includes: processing a base substrate to form a centrally protruding structure having a height that decreases in a radially outward direction from a center of the base substrate to an outer periphery of the base substrate; connecting a first side of the base substrate having the centrally protruding structure to a piezoelectric layer so as to obtain a multilayer substrate; and thinning the piezoelectric layer of the multilayer substrate followed by polishing a surface of the piezoelectric layer.

A method for making a composite substrate of a filter includes: processing a base substrate to form a centrally protruding structure having a height that decreases in a radially outward direction from a center of the base substrate to an outer periphery of the base substrate; connecting a first side of the base substrate having the centrally protruding structure to a piezoelectric layer so as to obtain a multilayer substrate; and thinning the piezoelectric layer of the multilayer substrate followed by polishing a surface of the piezoelectric layer.

A piezoelectric device includes a first substrate that includes a piezoelectric element (32) provided in a first region where bending deformation is allowed and an electrode layer (39) electrically connected to the piezoelectric element (32), a second substrate in which a bump electrode (43) abutting and conducting the electrode layer (39), and having elasticity is formed, and which is disposed so as to face the piezoelectric element (32) with a predetermined space, and adhesive (43) that bonds the first substrate and the second substrate in a state where a distance between the first substrate and the second substrate is maintained. The adhesive (43) has a width in a center portion in a height direction relative to a surface of the first substrate or the second substrate greater than a width in end portions in the same direction.

A substrate includes a substrate main body that includes a first main surface and a second main surface facing the first main surface. First electrode lands are disposed inside a recessed portion of the first main surface of the substrate main body. Second electrode lands are disposed in a region outside the recessed portion. The first electrode land and the second electrode land are connected to different electric potentials.

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.

A vibrating plate-bonded body includes a supporting substrate composed of silicon, a vibrating plate composed of a highly rigid ceramics and having a thickness of 100 μm or smaller, and a bonding layer between the supporting substrate and vibrating plate, contacting a bonding surface of the vibrating plate and composed of α-Si. The arithmetic average roughness Ra of the bonding surface of the vibrating plate is 0.01 nm or more and 10.0 nm or less, and the pit density of the bonding surface of the vibrating plate is 10 counts or more per 100 μm.sup.2.

Disclosed are systems, devices and methods for providing fingerprint sensors based on ultrasound imaging techniques in electronic devices and fabrication techniques for producing ultrasound-based fingerprint sensors. In some aspects, an ultrasound fingerprint sensor device includes an intermediate layer coupled to a base chip including an integrated circuit having conducive contacts at a surface of the base chip, the intermediate layer including an insulation layer formed on the base chip and a corresponding array of channeling electrode structures coupled to the conductive contacts and passing through the insulation layer, in which the channeling electrodes terminate at or above a top surface of the insulation layer to provide bottom electrodes; a plurality of ultrasonic transducer elements including an acoustic transducer material coupled to the bottom electrodes; and a plurality of top electrodes positioned on the ultrasonic transducer elements.

A semiconductor module and a method for manufacturing the same are provided. The semiconductor module includes a substrate comprising a front side and at least one semiconductor device formed on the front side, a shielding structure formed on the at least one semiconductor device, and a piezoelectric layer formed on the shielding structure.

A composite substrate includes a single crystal support substrate containing first element as a main component; an oxide single crystal layer provided on the single crystal support substrate and containing a second element (excluding oxygen) as a main component; and an amorphous layer provided in between the single crystal support substrate and the oxide single crystal layer and containing a first element, a second element, and Ar, the amorphous layer having a first amorphous region in which proportion of the first element is higher than proportion of the second element, and a second amorphous region in which the proportion of the second element is higher than the proportion of the first element, concentration of Ar contained in the first amorphous region being higher than concentration of Ar contained in the second amorphous region and being 3 atom % or more.