The present disclosure relates to a piezoelectric single-crystal element, a MEMS device using same, and a method for manufacturing same, wherein the piezoelectric single-crystal element includes a wafer, a lower electrode stacked on the wafer, a piezoelectric single-crystal thin film stacked on the lower electrode, and an upper electrode stacked on the piezoelectric single-crystal thin film, wherein the piezoelectric single-crystal thin film is composed of PMN-PT, PIN-PMN-PT or Mn:PIN-PMN-PT, and the piezoelectric single-crystal thin film has a polarization direction set to a <001> axis, a <011> axis or a <111> axis, and a MEMS device using same.

The present disclosure relates to a piezoelectric single-crystal element, a MEMS device using same, and a method for manufacturing same, wherein the piezoelectric single-crystal element includes a wafer, a lower electrode stacked on the wafer, a piezoelectric single-crystal thin film stacked on the lower electrode, and an upper electrode stacked on the piezoelectric single-crystal thin film, wherein the piezoelectric single-crystal thin film is composed of PMN-PT, PIN-PMN-PT or Mn:PIN-PMN-PT, and the piezoelectric single-crystal thin film has a polarization direction set to a <001> axis, a <011> axis or a <111> axis, and a MEMS device using same.

In a non-limiting embodiment, a device may include a substrate, and a hybrid active structure disposed over the substrate. The hybrid active structure may include an anchor region and a free region. The hybrid active structure may be connected to the substrate at least at the anchor region. The anchor region may include at least a segment of a piezoelectric stack portion. The piezoelectric stack portion may include a first electrode layer, a piezoelectric layer over the first electrode layer, and a second electrode layer over the piezoelectric layer. The free region may include at least a segment of a mechanical portion. The piezoelectric stack portion may overlap the mechanical portion at edges of the piezoelectric stack portion.

There is provided a laminated substrate having a piezoelectric film, including: a substrate; and a piezoelectric film provided on the substrate interposing a base film, wherein the piezoelectric film has an alkali niobium oxide based perovskite structure represented by a composition formula of (K.sub.1-xNa.sub.x)NbO.sub.3 (0<x<1) and preferentially oriented in (001) plane direction, and a sound speed of the piezoelectric film is 5100 m/s or more.

There is provided a laminated substrate having a piezoelectric film, including: a substrate; and a piezoelectric film provided on the substrate interposing a base film, wherein the piezoelectric film has an alkali niobium oxide based perovskite structure represented by a composition formula of (K.sub.1-xNa.sub.x)NbO.sub.3 (0<x<1) and preferentially oriented in (001) plane direction, and a sound speed of the piezoelectric film is 5100 m/s or more.

A method for separating a removable composite structure using a light flux includes supplying the removable composite structure, which successively comprises: a substrate that is transparent to the light flux; an optically absorbent layer for at least partially absorbing a light flux; a sacrificial layer adapted to dissociate subject to the application of a temperature higher than a dissociation temperature and made of a material different from that of the optically absorbent layer; and at least one layer to be separated. The method further includes applying a light flux through the substrate, the light flux being at least partly absorbed by the optically absorbent layer, so as to heat the optically absorbent layer; heating the sacrificial layer by thermal conduction from the optically absorbent layer, up to a temperature that is greater than or equal to the dissociation temperature; and dissociating the sacrificial layer under the effect of the heating.

Methods of manufacturing a pressure sensor from an SOI wafer are provided. In preferred embodiments, the methods comprise forming a cavity in a SOI wafer by removing a first portion of a bottom silicon layer on the bottom side of the SOI wafer to a depth of an insulator layer; depositing a layer of a second material over the cavity; removing both the silicon layer and the insulator layer from a top side of the SOI wafer in a first plurality of areas above the cavity to form a diaphragm from the layer of a second material, wherein at least one support structure that spans the diaphragm is formed from material above the cavity that was not removed; and forming at least one piezoresistor in the SOI wafer over an intersection of the support structure and SOI wafer at an outside edge of the diaphragm.

In a piezoelectric device, electrode layers are spaced apart from each other in the direction of the normal thereto. A first piezoelectric layer is interposed between two electrode layers of electrode layers in the direction of the normal. A second piezoelectric layer is provided on an opposite side of the first piezoelectric layer from a base portion. The second piezoelectric layer is interposed between two electrode layers of the electrode layers in the direction of the normal. The half-width of a rocking curve measured by X-ray diffraction for a lattice plane of the first piezoelectric layer substantially parallel to a first main surface is smaller than a half-width for the second piezoelectric layer. The piezoelectric constant of a material defining the first piezoelectric layer is smaller than the piezoelectric constant of a material defining the second piezoelectric layer.

A vortex-induced vibration wind energy harvesting device, including an array consisting of a plurality of oscillators and a plurality of piezoelectric microelectromechanical systems (MEMSs), is provided. An oscillator is mounted on each of the piezoelectric MEMSs. When any one of the oscillators is oscillated by and resonant with vortex shedding due to an incoming airflow, its vortices in the wake will enhance the oscillation of the downstream oscillators, so that overall oscillation of the oscillators in the array is strengthened. The piezoelectric MEMSs are deformed by the vibration of these oscillators to generate voltage and current to output. In the present invention, the oscillators are arranged closely. When the airflow passes the array, even weak airflow can generate periodic force and cause significant oscillation due to resonance. The MEMS can convert mechanical energy into electrical energy and output it in order to achieve the purpose of wind energy harvesting.

Piezoelectric transducers are provided. The piezoelectric transducer includes a first piezoelectric layer, a second piezoelectric layer disposed on at least a portion of the first piezoelectric layer, and a middle electrode layer disposed between the first and second piezoelectric layers, where the middle electrode layer includes an inner region and an outer region spaced apart from the inner region. Methods of making the piezoelectric transducers are also provided. The piezoelectric transducers and methods find use in a variety of applications, including devices, such as electronics devices having one or more (e.g., an array) of the piezoelectric transducers.