An ultrasound sensor includes a substrate in which a space is formed, a diaphragm provided on the substrate so as to block the space, a piezoelectric element which is provided on the diaphragm and includes a first electrode, a piezoelectric layer, and a second electrode, and an acoustic matching layer provided on a periphery of the piezoelectric element or in the space, in which the diaphragm has a bend in which a region corresponding to the space becomes convex (upwardly convex) to the opposite side to the space in a state where a voltage is not applied to the piezoelectric element, and a relaxation time of the polarization of the piezoelectric layer in the piezoelectric element is a repeating transmission period of the ultrasound sensor or less.

A piezoelectric material contains: a first component which is a rhombohedral crystal in a single composition, has a Curie temperature Tc1, and is a lead-free-system composite oxide having a perovskite-type structure; a second component which is a crystal other than the rhombohedral crystal in a single composition, has a Curie temperature Tc2<Tc1, and is a lead-free-system composite oxide having a perovskite-type structure; and a third component which is a crystal other than the rhombohedral crystal in a single composition similar to the second component, has a Curie temperature Tc3Tc1, and is a lead-free-system composite oxide that has a perovskite-type structure and is different from the second component. When a molar ratio of the third component to the sum of the second component and the third component is and Tc3+(1)Tc2 is Tc4, |Tc4Tc2|50 C.

The present disclosure relates to a process for annealing poled ceramic over a heating period during which the temperature is raised incrementally to lock-in desirable high temperature characteristics.

Aspects of the present disclosure relate to a piezoelectric device having at least one piezoelectric element, which has a support plane oriented to a force introduction element, wherein in the event of a thermal loading of the piezoelectric device in the support plane, expansion differences between the piezoelectric element and the force introduction element occur. To compensate for shear loadings, at least one transition element is arranged between the piezoelectric element and the force introduction element, the E-module of which is smaller than the E-module of the piezoelectric element in the support plane.

The present invention relates to a piezoelectric ceramic stacked structure, and the piezoelectric ceramic stacked structure includes at least one first layer including a KNN-based ceramic; and at least one second layer including a BFO-based ceramic, wherein a ratio of a number (n1) of the first layers stacked to a number (n2) of the second layers stacked in the piezoelectric ceramic stacked structure satisfies Equation (1) below:

0.8?|q|/|p|?n1/n2?1.2?|q|/|p|(1) (Equation (1) is as defined in the Description).

A method of imaging infrared light is provided which comprises: exciting ultrasonic waves in a metal pillar (e.g., Cu pillar); measuring the Time-of-Flight (ToF) of the ultrasonic wave in the waveguide; whereas the ToF is a function of incident Infrared light energy on the waveguide, and reporting the infrared light energy to capture an image. An apparatus of imaging infrared light is provided which comprises: a transducer; a waveguide coupled with the transducer; and a pixel electronic circuit coupled to the transducer, wherein the transducer includes one or more of: PZT, LiNb, AlN, or GaN.

The present invention relates to a heterojunction semiconductor substrate having excellent dielectric properties, a method of manufacturing the same, and an electronic device using the same. The present invention provides a heterojunction semiconductor substrate with improved interlayer adhesion, low leakage current, and excellent dielectric properties that maintain strength in a ferroelectric fatigue experiment by interposing a metal layer and a conductive metal oxide layer on a semiconductor substrate to form an epitaxial oxide thin film layer composed of perovskite piezoelectric oxide. The heterojunction semiconductor substrate can be applied to sensors, actuators, transducers, or MEMS devices that use the high functionality of the high-quality epitaxial oxide thin film layer, including applications in electronic and optical devices.

An apparatus is provided which comprises: a ferromagnetic (FM) region with magnetostrictive (MS) property; a piezo-electric (PZe) region adjacent to the FM region; and a magnetoelectric region adjacent to the FM region. An apparatus is provided which comprises: a FM region with MS property; a PZe region adjacent to the FM region; and a magnetoelectric region, wherein the FM region is at least partially adjacent to the magnetoelectric region. An apparatus is provided which comprises: a FM region with MS property; a PZe region adjacent to the FM region; a magnetoelectric region being adjacent to the FM and PZe regions; a first electrode adjacent to the FM and PZe regions; a second electrode adjacent to the magnetoelectric region; a spin orbit coupling (SOC) region adjacent to the magnetoelectric region; and a third electrode adjacent to the SOC region.

Discussed is a piezoelectric device that can include a piezoelectric device layer, a first electrode layer at a first surface of the piezoelectric device layer, and a second electrode layer at a second surface, differing from the first surface, of the piezoelectric device layer, wherein the piezoelectric device layer includes a first vibration portion and a second vibration portion each provided on a same plane to have different characteristics.

A piezoelectric thin-film element includes a first electrode layer, a piezoelectric thin film stacked on the first electrode layer, and a second electrode layer stacked on the piezoelectric thin film. A performance index P of the piezoelectric thin film is defined as (d.sub.33,f).sup.2?Y/?. d.sub.33,f is a piezoelectric strain constant of thickness longitudinal vibration of the piezoelectric thin film. Y is a Young's modulus of the piezoelectric thin film. ? is a permittivity of the piezoelectric thin film. The performance index P is from 10% to 80.1%.