A piezoelectric micromachined ultrasonic transducer (pMUT) device may include a piezoelectric membrane transducer designed to have lower sensitivity to residual stress and reduced sensitivity to geometric variations arising from the backside etching process used to release the membrane. These designs allow some of its key feature to be adjusted to achieve desired characteristics, such as pressure sensitivity, natural frequency, stress sensitivity, and bandwidth.

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

An input element includes: a first electrode and a second electrode that face each other; and an intermediate layer disposed between the first and the second electrodes and made of rubber or a rubber composition, the rubber or rubber composition containing siloxane. The intermediate layer is made of rubber or a rubber composition, the rubber or rubber composition containing siloxane that has a silicon atom bound to three to four oxygen atoms. The intermediate layer has concentration profiles such that, while oxygen increases from one side to the other side of a thickness direction thereof and has a maximal value, carbon decreases from the one side to the other side thereof and has a minimal value.

A piezoelectric device and a manufacturing method thereof in which a piezoelectric film formed of a thin film of a lead zirconate titanate-based perovskite oxide is formed on a substrate, and at least a first region out of the first region and a second region of the piezoelectric film is irradiated with electromagnetic waves having a wavelength of 230 nm or less in a reducing atmosphere to provide a difference in piezoelectric characteristics between the first region and the second region so that the first region has a smaller absolute value of a piezoelectric constant d.sub.31 and a smaller dielectric loss tan δ than the second region.

A method is provided for manufacturing a dielectric elastomer transducer including a dielectric elastomer layer and electrode layers sandwiching the elastomer layer. The elastomer layer when stretched exhibits a stress-strain curve having: a low strain and high elasticity region; a low elasticity region; and a high strain region. The method includes: a pre-stretching process to reduce hysteresis in elastic behavior of the elastomer layer by stretching the elastomer layer one or more times under a load as heavy as a first load before the electrodes are provided, each stretching causing the elastomer layer to undergo a tension falling in the low elasticity region; and a dielectric elastomer layer fixing process including applying a second load smaller than the first load to the elastomer layer so as to fix the elastomer layer to a support member under a second tension smaller than the first tension.

Embodiments of the present disclosure can include a method for frequency trimming a microelectromechanical resonator, the resonator comprising a substrate and a plurality of loading elements layered on a surface of the substrate, the method comprising: selecting a first loading element of the plurality of loading elements, the first loading element being layered on a surface of a region of interest of the substrate; heating the first loading element and substrate within the region of interest to a predetermined temperature using an optical energy source, causing the first loading element to diffuse into the substrate; and cooling the region of interest to form a eutectic composition layer bonding the loading element and the substrate within the region of interest.

A device and method for producing said device comprising an improved ultrasonic biometric sensor is disclosed. The ultrasonic biometric sensor is composed of a pixel array and multiple copolymer layers which are polarized in such a fashion as to increase the transmitting pressure and receiving sensitivity of the sensor. The copolymer layers may be polarized in the same direction, or in opposite directions, depending on the desired functionality.

A method for processing a lithium tantalate crystal substrate includes providing a lithium tantalate crystal substrate, roughening the lithium tantalate crystal substrate, providing a catalytic agent, bringing the lithium tantalate crystal substrate and the catalytic agent into contact with each other after the lithium tantalate crystal substrate is roughened, and subjecting the lithium tantalate crystal substrate to a reduction treatment. The reduction treatment is conducted at a temperature not higher than a Curie temperature of the lithium tantalate crystal substrate. The catalytic agent is selected from the group consisting of metal powder, metal gas, and metal carbonate powder.

A method for manufacturing an inkjet print head includes determining a misfit strain-electric field crystal phase relation for at least one composition of a piezoelectric material; selecting a misfit strain value and a composition of the piezoelectric material based on the determined misfit strain-electric field crystal phase relation for said at least one composition; and based on the selected misfit strain and the selected composition of the piezoelectric material, forming a base layer and an actuator stack on the base layer, the actuator stack including the piezoelectric material, wherein the base layer and the actuator stack have predetermined properties providing the selected misfit strain value and the selected composition. Thus, an inkjet print head having a piezoelectric actuator that is operated on the basis of a crystal phase change is reliably manufacturable.

A microelectromechanical system (MEMS) resonator includes a degenerately-doped single-crystal silicon layer and a piezoelectric material layer disposed on the degenerately-doped single-crystal silicon layer. An electrically-conductive material layer is disposed on the piezoelectric material layer opposite the degenerately-doped single-crystal silicon layer, and patterned to form first and second electrodes.