An acoustic wave resonator includes: a piezoelectric substrate; a pair of comb-shaped electrodes that is located on the piezoelectric substrate and excites an acoustic wave, each of the pair of comb-shaped electrodes including a plurality of electrode fingers; and a polycrystalline substrate that is located at an opposite side of the piezoelectric substrate from a surface on which the pair of comb-shaped electrodes is located, an average particle size of the polycrystalline substrate being equal to or less than 66 times an average pitch of the plurality of electrode fingers.

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.

A sensor system includes a sensor stack, a differential amplifier, an analog-to-digital converter, and a processor. The sensor stack includes a piezoelectric material having a first side opposing a second side, a first electrode connected to the first side, and a second electrode connected to the second side. The differential amplifier is coupled to the first and second electrodes and is configured to generate a differential output indicative of vibrations sensed by the piezoelectric material. The analog-to-differential converter is configured to digitize the differential output. The processor is configured to identify a type of biological vibration included in the digitized differential output.

A processing device forms, in an object to be processed, a modified spot constituting a modified region. The processing device includes a first irradiation unit configured to irradiate the object with first light to temporarily increase absorptivity in a partial region of the object as compared with the absorptivity before irradiation of the first light, and a second irradiation unit configured to irradiate the partial region with second light in an absorptivity increase period in which the absorptivity of the partial region is temporarily increased.

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.

An ultrasound system, probe and method are provided. The ultrasound system includes a transducer with piezoelectric transducer elements polarized in a poling direction. A bipolar transmit circuit is configured to generate a transmit signal having first and second polarity segments. The first and second polarity segments have corresponding first and second peak amplitudes. A bias generator is configured to generate a bias signal in a direction of the poling direction. The bias signal is combined with the transmit signal to form a biased transmit signal that is shifted in the direction of the poling direction and still includes both of positive and negative voltages over a transmit cycle.

High performance single crystal silicon cells and arrays thereof are manufactured using a rapid process flow. Tunneling junctions formed in the process provide performance benefits, such as higher efficiency and a lower power temperature coefficient. The process generates a large array of interconnected high performance cells smaller than typical cells without requiring additional process steps, and simplifies integration of these coupons into the final product. The cells can have different shapes, sizes, and orientations, enabling the array to be flexible in any desired direction. Higher efficiencies and lower hot spotting under shading is achieved by connecting small low current, high voltage cells in dense series and parallel configurations. Low current cells also require much less metallization than typical solar cells and arrays.

A transducer comprising a transducer element including a plate with a through-hole and a collar projecting from the plate and defining an interior cavity in communication with the through-hole. A piezoelectric bender includes at least first and second wafer layers stacked together. The bender is coupled to a peripheral end face of the collar. The first and/or second piezoelectric wafer layers bend at a resonant frequency and generate ultrasonic waves that flow through the collar interior cavity and the plate through-hole and create an in-air pressure pattern and acoustic field at a location spaced from the transducer. A plurality of transducers may be made by providing a monolithic transducer element structure including a plurality of the transducer elements formed thereon, coupling either a plurality of benders or a monolithic bender to the plurality of transducer elements, and then cutting the monolithic transducer element structure to define a plurality of individual transducers.

Systems and techniques are provided for piezoelectric transducer array fabrication. A sheet of piezoelectric material may be diced into pieces of piezoelectric material. A sheet of elastic layer material may be spin coated with adhesive. The pieces of piezoelectric material may be placed onto the sheet of elastic layer material. Pressure may be applied to the pieces of piezoelectric material and the sheet of elastic layer material. The adhesive may be cured. Transduction elements may be cut from the pieces of piezoelectric material and the sheet of elastic layer material. Electronics may be mounted on a PCB mounting board. Adhesive may be applied onto the PCB mounting board. The transduction elements may be mounted on the PCB mounting board. A spacer may be mounted on the PCB mounting board. Adhesive may be applied onto the spacer and the transduction elements. Diaphragms may be mounted on the spacer.

A method for making ultrasound transducers and ultrasound probes includes providing a piezoelectric layer having a first surface and a second surface, where the second surface is on an opposite side of the piezoelectric layer from the first surface. The method includes fabricating a plurality of conductive through vias extending from the first surface to the second surface of the piezoelectric layer, where fabricating the plurality of conductive through vias comprises cutting a plurality of trenches through the piezoelectric layer and filling each of the plurality of trenches with a conductive material. The method includes cutting the piezoelectric layer into a plurality of transducer units after fabricating the plurality of conductive through vias and cutting each of the transducer units into a plurality of transducer elements.