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.

The present disclosure of at least one embodiment provides a method for manufacturing ultrasound probes comprising a machining process, the method including depoling a piezoelectric element as a material for the ultrasonic probes before the machining process.

In manufacturing method of a cylindrical piezoelectric element, a cylindrical piezoelectric material is formed by molding a piezoelectric material into a cylindrical shape and subjecting the molded piezoelectric material to calcination. A reference electrode is provided on an inner circumferential surface of the cylindrical piezoelectric material. Drive electrodes are provided in a circumferential direction so that the drive electrodes are extending in an axial direction from one end to the other end on an outer circumferential surface. A polarization electrode is provided at a part of the circumferential surface in the vicinity of the one end. A predetermined voltage is applied between the polarization electrode and the reference electrode. The polarization electrode is removed from the cylindrical piezoelectric material.

A method for transferring a piezoelectric layer from a donor substrate onto a support substrate comprises the steps of: a) providing a predetermined splitting area in a piezoelectric donor substrate, b) attaching the piezoelectric donor substrate to a support substrate to form an assembly, and c) detaching the piezoelectric layer from the piezoelectric donor substrate comprising applying an electric field. By using the electric field, the detachment step can be carried out at low temperatures. A detachment chamber for carrying out at least a portion of such a method includes one or two chucks comprising first and/or second electrodes for applying an electric field to a piezoelectric layer.

A method of manufacturing a substrate for an acoustic wave device includes: a substrate joining step of joining a piezoelectric material layer to a surface on one side of a support substrate; a grinding step of grinding the piezoelectric material layer; a removal amount map forming step of measuring in-plane thickness of the piezoelectric material layer by an optical thickness meter, and calculating a removal amount for the piezoelectric material layer for adjusting thickness variability of the piezoelectric material layer to or below a threshold on the basis of each coordinate in the plane, to form a removal amount map; a laser processing step of applying a pulsed laser beam of such a wavelength as to be absorbed in the piezoelectric material layer, to selectively remove the piezoelectric material layer, based on the removal amount map; and a polishing step of polishing the surface of the piezoelectric material 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 vibration element includes a piezoelectric piece having a main surface; an excitation electrode disposed on the main surface of the piezoelectric piece; and a connection electrode disposed on the main surface of the piezoelectric piece and electrically connected to the excitation electrode, wherein when the main surface of the piezoelectric piece is viewed in a plan, the piezoelectric piece has a through-hole in an area between the excitation electrode and the connection electrode, and wherein an internal wall of the through-hole located closer to the excitation electrode has at least four slopes.

A method for producing a plurality of piezoelectric multilayer components is disclosed. In an embodiment, a method for producing a plurality of piezoelectric multilayer components includes grinding the piezoelectric multilayer components without an addition of an abrasive by rubbing the piezoelectric multilayer components against one another so that a material abrasion of the piezoelectric multilayer components is carried out.

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.

A composite wafer has an oxide single-crystal film transferred onto a support wafer, the film being a lithium tantalate or lithium niobate film, and the composite wafer being unlikely to have cracking or peeling caused in the lamination interface between the film and the support wafer. More specifically, a method of producing the composite wafer, includes steps of: implanting hydrogen atom ions or molecule ions from a surface of the oxide wafer to form an ion-implanted layer inside thereof; subjecting at least one of the surface of the oxide wafer and a surface of the support wafer to surface activation treatment; bonding the surfaces together to obtain a laminate; heat-treating the laminate at 90 C. or higher at which cracking is not caused; and applying ultrasonic vibration to the heat-treated laminate to split along the ion-implanted layer to obtain the composite wafer.