A process for preparing a thin layer made of ferroelectric material based on alkali metal, exhibiting a determined Curie temperature, transferred from a donor substrate to a carrier substrate by using a transfer technique including implanting light species into the donor substrate in order to produce an embrittlement plane, the thin layer having a first, free face and a second face that is arranged on the carrier substrate. The process comprises a first heat treatment of the transferred thin layer at a temperature higher than the Curie temperature, the thin layer exhibiting a multi-domain character upon completion of the first heat treatment, and introducing, after the first heat treatment, protons into the thin layer, followed by applying a second heat treatment of the thin layer at a temperature lower than the Curie temperature to generate an internal electric field that results in the thin layer being made single domain.

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.

A multi-layer piezoelectric microactuator assembly has at least one poled and active piezoelectric layer and one poled but inactive piezoelectric layer. The poled but inactive layer acts as a constraining layer in resisting expansion or contract of the first piezoelectric layer thereby reducing or eliminating bending of the assembly as installed in an environment, thereby increasing the effective stroke length of the assembly. Poling only a single layer would induce stresses into the device; hence, polling both piezoelectric layers even though only one layer will be active in use reduces stresses in the device and therefore increases reliability.

A heat-dissipating component for a mobile device includes a case body, a micro pump, and a heat dissipation tube plate. The case body has a vent hole and a positioning accommodation trough. The bottom of the positioning accommodation trough is in communication with the vent hole. The micro pump is disposed in the positioning accommodation trough and corresponds to the vent hole The heat dissipation tube plate has cooling fluid inside. One end of the heat dissipation tube plate is fixed on the positioning accommodation trough and contacts a heating element of the mobile device. The gas transmitted by the micro pump forms gas flow so as to perform heat exchange with heat absorbed by the heat dissipation tube plate, and the gas flow is discharged out through the vent hole.

A sensor for obtaining downhole data includes a first piezoelectric layer. The sensor also includes a second piezoelectric layer having a trench extending a depth below a surface of the second piezoelectric layer. The sensor also includes an electrode positioned within the trench. The first piezoelectric layer is directly coupled to the second piezoelectric layer.

An elastic wave device using the S0 mode of plate waves includes a support substrate, an acoustic reflective layer laminated on the support substrate, a piezoelectric body laminated on the acoustic reflective layer, and an IDT electrode disposed on the piezoelectric body. In the acoustic reflective layer, T1+T2 is between about 0.40 and about 0.60 inclusive in a portion in which low and high acoustic impedance layers are adjacent in the laminating direction. T1 is the thickness of the low acoustic impedance layers. T2 is the thickness of the high acoustic impedance layers. T1/(T1+T2) is between about 0.35 and about 0.65 inclusive.

An elastic wave device using the S0 mode of plate waves includes a support substrate, an acoustic reflective layer laminated on the support substrate, a piezoelectric body laminated on the acoustic reflective layer, and an IDT electrode disposed on the piezoelectric body. In the acoustic reflective layer, T1+T2 is between about 0.40 and about 0.60 inclusive in a portion in which low and high acoustic impedance layers are adjacent in the laminating direction. T1 is the thickness of the low acoustic impedance layers. T2 is the thickness of the high acoustic impedance layers. T1/(T1+T2) is between about 0.35 and about 0.65 inclusive.

Piezoelectrically actuated devices constructed from thin semiconductor membranes bonded directly to piezoelectric substrates are provided. Methods for fabricating these devices are also provided. The bonding of the semiconductor to the piezoelectric material does not require the use of any intermediate layers, such as bonding agents.

Electromagnetically transparent conductive materials, in particular nanomaterials, are used in a sensor along with piezoelectric materials to detect the motion of a subject to provide respiratory and cardiac gating for imaging techniques such as MRI, CT scans and PET.

A piezoelectric device and a fabricating method thereof, and an electronic device and a controlling method thereof, which relates to the technical field of piezoelectric devices. The piezoelectric device includes: a flexible substrate and a plurality of piezoelectric units that are provided on the flexible substrate and are arranged in an array; each of the plurality of piezoelectric units includes: a first electrode, a piezoelectric component and a second electrode that are sequentially stacked on the flexible substrate; and the piezoelectric component is made from a rigid material. The present disclosure is suitable for the fabrication of piezoelectric devices.