An optical element includes a primary electrode, a secondary electrode overlapping at least a portion of the primary electrode, and an electrostrictive ceramic layer disposed between and abutting the primary electrode and the secondary electrode, where the electrostrictive ceramic may be characterized by a relative density of at least approximately 99%, an average grain size of at least approximately 300 nm, a transmissivity within the visible spectrum of at least approximately 70%, and bulk haze of less than approximately 10%. Optical properties of the electrostrictive ceramic may be substantially unchanged during the application of a voltage to the electrostrictive ceramic layer and the attendant actuation of the optical element.

Provided is a piezoelectric thin film device in which lattice mismatch between a piezoelectric thin film and a lower electrode layer (first electrode layer) is reduced. A piezoelectric thin film device 10 comprises a first electrode layer 6a and a piezoelectric thin film 2 laminated directly on the first electrode layer 6a; the first electrode layer 6a includes an alloy composed of two or more metal elements; the first electrode layer 6a has a body-centered cubic lattice structure; and the piezoelectric thin film 2 has a wurtzite structure.

A piezo-junction device may be provided. The piezo-junction device comprises a piezoelectric element comprising two electrodes and piezoelectric material in-between, and a semiconductor junction device adjacent to the piezoelectric element such that one of the two electrodes of the piezoelectric element is in contact with the semiconductor junction device connecting the semiconductor junction device and the piezoelectric element electrically in series. Thereby, the semiconductor junction device and the piezoelectric element are together positioned in a fixed mechanical clamp such that the piezoelectric element with an applied electrical field applies strain to the semiconductor junction device causing a change in Fermi levels of the semiconductor junction device.

A thin film laminate comprises a metal layer consisting of a metal, and a thin film laminated on the surface of the metal layer, wherein a first direction is defined as one direction parallel to the surface of the metal layer, and a second direction is defined as one direction parallel to the surface of the metal layer and crossing the first direction; and the metal layer contains a plurality of first metal grains consisting of the metal and extending in the first direction on the surface of the metal layer, and a plurality of second metal grains consisting of the metal and extending in the second direction on the surface of the metal layer.

A diaphragm for a piezoelectric micromachined ultrasonic transducer (PMUT) is presented having resonance frequency and bandwidth characteristics which are decoupled from one another into independent variables. Portions of at least the piezoelectric material layer and backside electrode layer are removed in a selected pattern to form structures, such as ribs, in the diaphragm which retains stiffness while reducing overall mass. The patterned structure can be formed by additive, or subtractive, fabrication processes.

A piezoelectric film including a piezoelectric body configured to extract radio waves of a required frequency by resonance is provided. The piezoelectric body is based on either of ScAlN or AlN, and an X-ray rocking curve full-width at half-maximum (FWHM) of the piezoelectric body in a lattice plane with a Miller index of (11-20) is not more than 10°.

A piezoelectric thin film includes a first piezoelectric layer and a second piezoelectric layer directly stacked on the first piezoelectric layer. The first piezoelectric layer contains a tetragonal crystal 1 of a perovskite-type oxide. The second piezoelectric layer contains a tetragonal crystal 2 of a perovskite-type oxide. A (001) plane of the tetragonal crystal 1 is oriented in a normal direction do of a surface of the piezoelectric thin film. A (001) plane of the tetragonal crystal 2 is oriented in the normal direction dn of the surface of the piezoelectric thin film. An interval of the (001) plane of the tetragonal crystal 1 is c1, an interval of a (100) plane of the tetragonal crystal 1 is a1, an interval of the (001) plane of the tetragonal crystal 2 is c2, an interval of a (100) plane of the tetragonal crystal 2 is a2, c2/a2 is more than c1/a1 and c1/a1 is from 1.015 to 1.050.

An electronic component includes a support member, a piezoelectric film, and an interdigital transducer. The support member includes silicon as a primary component. The piezoelectric film is provided directly or indirectly on the support member. The interdigital transducer includes a plurality of electrode fingers. The plurality of electrode fingers are provided side by side separately from each other. The interdigital transducer is provided on the principal surface of the piezoelectric film. The film thickness of the piezoelectric film is about 3.5 λ or less, where λ denotes the wavelength of an acoustic wave determined by the electrode finger pitch of the interdigital transducer. In the support member, the high-impurity-concentration region is further from the piezoelectric film than the low-impurity-concentration region.

A piezoelectric element that includes a substrate, a lower electrode layer on the substrate, an intermediate layer on the lower electrode layer, and an upper electrode layer on the intermediate layer. The intermediate layer includes a first piezoelectric layer including an aluminum nitride as a main component thereof and located between the lower electrode layer and the upper electrode layer, a first buffer layer including an aluminum nitride as a main component and located between the first piezoelectric layer and the upper electrode layer, a first intermediate electrode layer located between the first buffer layer and the upper electrode layer, and a second piezoelectric layer located between the first intermediate electrode layer and the upper electrode layer.

A MEMS structure may include a substrate, a first metal layer arranged over the substrate, an aluminum nitride layer at least partially arranged over the first metal layer and a second metal layer including one or more patterns arranged over the aluminum nitride layer. The first metal layer may include an electrode area configured for external electrical connection and one or more isolated areas configured to be electrically isolated from the electrode area and further configured to be electrically isolated from external electrical connection. Each pattern of the second metal layer may be arranged to at least partially overlap with one of the isolated area(s) of the first metal layer.