A multi-layered film includes an electroconductive layer made of platinum (Pt), a seed layer including lanthanum (La), nickel (Ni), and oxygen (O), and a dielectric layer being preferentially oriented in a c-axis direction, which are at least sequentially disposed on a main surface of a substrate made of silicon.

The embodiments herein relate to surface acoustic wave (SAW) devices, such as filters and duplexers. The SAW device may have a high acoustic velocity layer and a piezoelectric layer coupled to the high acoustic velocity layer. At least one transducer is coupled at least to the piezoelectric layer, where the transducer propagates a surface acoustic wave having an operating wavelength along a surface of the piezoelectric layer. A metallic layer may be coupled to the surface of the piezoelectric layer and electrically isolated from the transducer.

A bulk acoustic wave resonator includes a substrate on which a substrate protective layer is disposed, a membrane layer forming a cavity together with the substrate, and a resonant portion disposed on the membrane layer. The cavity is formed by removing a sacrificial layer using a mixed gas obtained by mixing a halide-based gas and an oxygen gas, and at least one of the membrane layer and the substrate protective layer has a thickness difference of 170 ? or less, after the cavity is formed.

An elastic wave device includes a piezoelectric substrate, an IDT electrode on the piezoelectric substrate, a support member that is provided on the piezoelectric substrate so as to surround the IDT electrode, a cover that covers the support member, via electrodes that penetrate through the support member and the cover, and bumps that are bonded to the via electrodes. The IDT electrode is located in a hollow space that is enclosed by the piezoelectric substrate, the support member and the cover. A protruding portion extends along at least a portion of an outer peripheral edge of a surface of the cover that is on the opposite side from the piezoelectric substrate, and the protruding portion extends in a direction away from the piezoelectric substrate.

An empty chamber component includes a pressure chamber formation substrate where a pressure chamber as an empty chamber is defined and a communication substrate bonded to the pressure chamber formation substrate. A piezoelectric element is provided on one side of the pressure chamber formation substrate. A flexible surface is located between the piezoelectric element and the pressure chamber. Empty portions are defined by the communication substrate closing recessed portions in the pressure chamber formation substrate. The empty portions are formed at positions where ends of the active section of the piezoelectric element pass through the empty portions in plan view.

In some embodiments, a piezoelectric device is provided. The piezoelectric device includes a semiconductor substrate. A first electrode is disposed over the semiconductor substrate. A piezoelectric structure is disposed on the first electrode. A second electrode is disposed on the piezoelectric structure. A heating element is disposed over the semiconductor substrate. The heating element is configured to heat the piezoelectric structure to a recovery temperature for a period of time, where heating the piezoelectric structure to the recovery temperature for the period of time improves a degraded electrical property of the piezoelectric device.

A semiconductor substrate and a package structure including the same are provided. The semiconductor substrate includes a first surface and a second surface. The first surface includes a filtering region. The second surface is opposite to the first surface and includes an amplifying region.

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 piezoelectric composite substrate for SAW devices with small loss is provided. A composite substrate for a surface acoustic wave device according to one embodiment of the present invention has a piezoelectric single crystal thin film, a support substrate, and a first intervening layer between the piezoelectric single crystal thin film and the support substrate. In said composite substrate, the first intervening layer is in contact with the piezoelectric single crystal thin film, and the acoustic velocity of the transverse wave in the first intervening layer is faster than the acoustic velocity of the fast transverse wave in the piezoelectric single crystal thin film.

An electro-acoustic component with improved acoustics is specified. The component comprises a rectangular chip whose side edges are rotated relative to the piezoelectric axis.