An interventional device (100, 200, 300) includes an elongate shaft (101) having a longitudinal axis A-A′, an ultrasound transducer (102), an adhesive layer (103), and a protective tube (104) formed from a protective tube (104) formed from a heat-shrink material. The ultrasound transducer (102) is disposed on the elongate shaft (101) such that the ultrasound transducer (102) has an axial extent L along the longitudinal axis A-A′, At least along the axial extent L of the adhesive layer (103) is disposed between the ultrasound transducer (102) and the protective tube (104) surrounds the ultrasound transducer (102) and the adhesive layer (103) is disposed between the ultrasound transducer (102) and the protective tube (104).

In one aspect, a microelectronic device comprises: a suspended lithium-based thin film; and one or more electrodes disposed on the suspended lithium-based thin film, wherein the one or more electrodes comprises one or more fingers, and a width of at least one outer finger of the one or more fingers is smaller than a width of at least one inner finger of the one or more fingers.

A piezoelectric element is obtained using a method including: preparing a first structure; preparing a second structure; disposing a first facing electrode layer of the first structure to face a first surface of a vibration plate substrate and bonding the first structure to the first surface of the vibration plate substrate; processing the vibration plate substrate into a vibration plate by polishing or etching a second surface of the vibration plate substrate to which the first structure is bonded; preparing a laminate structure by disposing a second facing electrode layer of the second structure to face an exposed surface of the vibration plate and bonding the second structure to the vibration plate; and removing at least a part of a first silicon substrate of the first structure and a second silicon substrate of the second structure from the laminate structure.

A bonded body includes a supporting substrate; a piezoelectric material substrate composed of a material selected from the group consisting of lithium niobate, lithium tantalate and lithium niobate-lithium tantalate; and a bonding layer bonding the supporting substrate and the piezoelectric material substrate and contacting a main surface of the piezoelectric material substrate. The bonding layer includes a void extending from the piezoelectric material substrate toward the supporting substrate. A ratio (t2/t1) of a width t2 at an end of the void on a side of the supporting substrate with respect to a width t1 at an end of the void on a side of the piezoelectric material substrate is 0.8 or lower.

The present disclosure provides a resonator and its fabrication method. The method includes providing a first substrate; forming a piezoelectric stacked layer-structure on the first substrate; forming a sacrificial layer covering the piezoelectric stacked layer-structure on a working region; providing a second substrate; forming an adhesive layer on the second substrate; attaching a second back surface of the adhesive layer to the sacrificial layer and the piezoelectric stacked layer-structure exposed by the sacrificial layer, where the adhesive layer covers sidewalls of the sacrificial layer and is filled between the second substrate and the piezoelectric stacked layer-structure; removing the first substrate to expose a first front surface of the piezoelectric stacked layer-structure; forming release holes passing through the piezoelectric stacked layer-structure, or forming release holes passing through the second substrate; and removing the sacrificial layer through the release holes to form a cavity.

An electronic device includes a first substrate and a second substrate. A side wall joins the first substrate to the second substrate. The side wall includes a first alloy layer of a first metal and a second metal bonded directly to an upper surface of the first substrate and a second alloy layer of the first metal and a third metal disposed on top of the first alloy layer and bonded directly to a lower surface of the second substrate, the second metal and the third metal being different from each other and from the first metal. An electronic circuit is disposed on the lower surface of the second substrate within a cavity defined by the lower surface of the first substrate, the upper surface of the second substrate, and the side wall.

A method for manufacturing a substrate for a radiofrequency filter by joining a piezoelectric layer to a carrier substrate via an electrically insulating layer, wherein the method comprises depositing the electrically insulating layer by spin coating an oxide belonging to the family of SOGs (spin-on glasses) on the surface of the piezoelectric layer to be joined to the carrier substrate, followed by an anneal for densifying the electrically insulating layer before joining the piezoelectric layer to the carrier substrate via the electrically insulating layer.

A vibration detection element (10) includes substrates (1 to 3), a support member (22), a support member (32), and an oscillator (4). The substrates (1 to 3) have a space portion (SP) having a bottom surface (21A) and a bottom surface (31A) opposed to the bottom surface (21A). The support member (22) protrudes from the bottom surface (21A) toward the bottom surface (31A) of the space portion (SP). The support member (32) protrudes from the bottom surface (31A) toward the bottom surface (21A) of the space portion. The oscillator (4) is disposed in contact with the support member (22) or the support member (32) and capable of vibrating in the space portion (SP) and has a thickness less than 10 μm. The support members (22, 32) each include multiple supports which prevent the oscillator (4) from contacting the bottom surface (21A) or the bottom surface (31A).

The present disclosure provides methods to integrate piezoelectric micromachined ultrasonic transducer (pMUT) arrays with an application-specific integrated circuit (ASIC) using thermocompression or eutectic/solder bonding. In an aspect, the present disclosure provides a device comprising a first substrate and a second substrate, the first substrate comprising a pMUT array and the second substrate comprising an electrical circuit, wherein the first substrate and the second substrate are bonded together using thermocompression, wherein any set of individual PMUTs of PMUT array is addressable. In another aspect, the present disclosure provides a device comprising a first substrate and a second substrate, the first substrate comprising a pMUT array and the second substrate comprising an electrical circuit, wherein the first substrate and the second substrate are bonded together using eutectic or solder bonding, wherein any set of individual PMUTs of the PMUT array is addressable.

The present invention relates to a heterostructure, in particular, a piezoelectric structure, comprising a cover layer, in particular, a layer of piezoelectric material, the material of the cover layer having a first coefficient of thermal expansion, assembled to a support substrate, the support substrate having a second coefficient of thermal expansion substantially different from the first coefficient of thermal expansion, at an interface wherein the cover layer comprises at least a recess extending from the interface into the cover layer, and its method of fabrication.