A process for fabricating a substrate for a radiofrequency device by joining a piezoelectric layer to a carrier substrate by way of an electrically insulating layer, the piezoelectric layer having a rough surface at its interface with the electrically insulating layer, the process being characterized in that it comprises the following steps: providing a piezoelectric substrate having a rough surface for reflecting a radiofrequency wave, depositing a dielectric layer on the rough surface of the piezoelectric substrate, providing a carrier substrate, depositing a photo-polymerizable adhesive layer on the carrier substrate, bonding the piezoelectric substrate to the carrier substrate by way of the dielectric layer and of the adhesive layer, in order to form an assembled substrate, irradiating the assembled substrate with a light flux in order to polymerize the adhesive layer, the adhesive layer and the dielectric layer together forming the electrically insulating layer.

A bonding layer 3 is formed over a piezoelectric material substrate, and the bonding layer is made of one or more materials selected from the group consisting of silicon nitride, aluminum nitride, alumina, tantalum pentoxide, mullite, niobium pentoxide and titanium oxide. A neutralized beam is irradiated onto a surface of the bonding layer and a surface of a supporting body to activate the surface of the bonding layer and the surface of the supporting body. The surface of the bonding layer and the surface of the supporting body are bonded by direct bonding.

An electronic device, such as a filter, includes a first substrate having a bottom surface and a top surface, a first side wall of a certain height being formed along a periphery of the bottom surface to surround an electronic circuit disposed on the bottom surface, an external electrode formed on the top surface, the external electrode being connected to the electronic circuit by a via communicating with the bottom surface and a second substrate. The second substrate has a second side wall of a certain height formed along a periphery of a top surface, the second side wall being aligned and bonded with the first side wall to internally form a cavity defined between the bottom surface of the first substrate, the top surface of the second substrate, the first side wall, and the second side wall.

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 disclosure provides methods to integrate pMUT arrays with an ASIC using solid liquid interdiffusion (SLID). In an aspect, the present disclosure provides a device comprising a first substrate and a second substrate, the first substrate comprising a pMUT device and the second substrate comprising an electrical circuit, wherein the first substrate and the second substrate are bonded together using a conductive bonding pillar, which conductive bonding pillar comprises one or more intermetallic compounds. In another aspect, the present disclosure provides a device comprising a first substrate and a second substrate, the first substrate comprising a pMUT device and the second substrate comprising an electrical circuit, wherein the first substrate and the second substrate are bonded together using a conductive bonding pillar, wherein the bonding is performed at a temperature less than the melting point of the conductive bonding pillar after the bonding.

A sleep monitor includes a layered sensor that includes at least one substrate layer that includes multiple laterally adjacent substrates. The substrate layer may be formed by interdigitating fingers of a first sheet with fingers of a second sheet. Combining multiple substrates in a single layer of a layered sensor may allow multiple materials and/or sensing mechanisms to be combined together in a single layer.

Provided is a nano-scale single crystal thin film. The nano-scale single crystal thin film comprises a nano-scale single crystal thin film layer, a first transition layer, an isolation layer, a second transition layer, and a substrate layer. The first transition layer is located between the nano-scale single crystal thin film layer and the isolation layer, while the second transition layer is located between the isolation layer and the substrate layer. The first transition layer comprises a certain concentration of the H element.

A method for fabricating an array of front ends for an array of packaged electronic components that each comprise:

an electrical element packaged within a package comprising
a front part of a package comprising an inner section with a cavity therein opposite the resonator defined by the raised frame and an outer section sealing said cavity; and
a back part of the package comprising a back cavity in an inner back section, and an outer back section sealing the cavity, said back package further comprising a first and a second via through the back end around said at least one back cavity for coupling to front and back electrodes of the electronic component; the vias terminating in external contact pads that are coupleable in a flip chip configuration to a circuit board; the method comprising the stages of: i. Obtaining a carrier substrate having an active membrane layer attached thereto by its rear surface, with a front electrode on the front surface of the active membrane layer; ii. Obtaining an inner front end section; iii. Attaching the inner front end section to the exposed front surface of the front electrode; iv. Detaching the carrier substrate from the rear surface of the active membrane layer; v. Optionally thinning the inner front section; vi. Processing the rear surface by removing material to create an array of at least one island of active membrane on at least one island of front electrode; vii. Creating an array of at least one front cavity by selectively removing at least outer layer of the inner front end section, such that there is one cavity opposite each island of membrane on the front side of the front electrode on the opposite side to the island of active membrane; viii. Applying an outer front end section to the inner front end section and bonding the outer front end section to an outer surface of the inner front end section such that the outer front end section spans across and seals the at least one cavity of the array of front cavities.

A method for transferring a piezoelectric layer onto a support substrate comprises:providing a donor substrate including a heterostructure comprising a piezoelectric substrate bonded to a handling substrate, and a polymerized adhesive layer at the interface between the piezoelectric substrate and the handling substrate,forming a weakened zone in the piezoelectric substrate, so as to delimit the piezoelectric layer to be transferred,providing the support substrate,forming a dielectric layer on a main face of the support substrate and/or of the piezoelectric substrate,bonding the donor substrate to the support substrate, the dielectric layer being at the bonding interface, andfracturing and separating the donor substrate along the weakened zone at a temperature below or equal to 300 C.

In an acoustic wave device including a piezoelectric material substrate and supporting body bonded with each other through a bonding layer, it is an object to provide the acoustic wave device having the structure for further improving the propagation loss and temperature characteristics of frequency of an acoustic wave. An acoustic wave device includes a piezoelectric material substrate, an electrode on the piezoelectric material substrate, a supporting body, and a bonding layer for bonding the piezoelectric material substrate and the supporting body. The bonding layer is composed of quartz crystal.