Acoustic filtering circuitry includes a piezoelectric layer, a dielectric layer, a plurality of acoustic resonators, and a capacitor. The dielectric layer is over a surface of the piezoelectric layer. The plurality of acoustic resonators each includes a transducer on the surface of the piezoelectric layer such that the transducer is between the piezoelectric layer and the dielectric layer. The capacitor includes a first plate on the surface of the piezoelectric layer such that the first plate is between the piezoelectric layer and the dielectric layer and a second plate over the first plate such that the second plate and the first plate are separated by at least a portion of the dielectric layer.

In one embodiment, a bonded quartz wafer package includes a first quartz wafer including at least one quartz-based device, a second quartz wafer disposed above the first quartz wafer, and a liquid crystal polymer (LCP) bonding layer disposed in between the first and second quartz wafers that bonds the first and second quartz wafers together.

A surface acoustic wave resonator includes first and second surface acoustic wave resonator connected in series, and a third surface acoustic wave resonator connected in series with the second surface acoustic wave resonator. Each of the first to third surface acoustic wave resonators includes a pair of comb-shaped electrodes in which electrode fingers of one of the comb-shaped electrodes and electrode fingers of the other one of the comb-shaped electrodes are alternately arranged. The second surface acoustic wave resonator has a lower ratio of a width of the electrode fingers to a pitch between the electrode fingers than the first and third surface acoustic wave resonators.

A package structure of an air gap type semiconductor device includes a carrier; a semiconductor chip; and a bonding layer disposed between the carrier and the semiconductor chip. A first cavity is formed in the bonding layer and enclosed by the semiconductor chip and the carrier to at least aligned with a portion of an active region of the semiconductor chip. An encapsulation layer and the bonding layer are on a same side of the carrier to encapsulate the semiconductor chip and an exposed region of the bonding layer. At least one portion of the encapsulation layer is formed between the semiconductor chip and the carrier along a direction perpendicular to a lateral surface of the carrier. Interconnection structures formed on a side of the carrier different from a side with the bonding layer. Each interconnection structure is electrically connected to a corresponding input/output electrode of the semiconductor chip.

A method of making an acoustic wave sensor includes the steps of providing a piezoelectric substrate layer and printing on the substrate layer a sensor layer comprising a first interdigitated acoustic wave transducer, a sensing film, and positioned on an opposing side of the sensing film from the first interdigitated acoustic wave transducer at least one selected from the group consisting of a second interdigitated acoustic wave transducer and a Bragg reflector. An insulation layer can be printed. An antenna can be printed in an antenna layer, and the insulation layer can be interposed between the antenna layer and the sensor layer. An electrical connection can be printed between the antenna and the first interdigitated acoustic wave transducer. An acoustic wave sensor is also disclosed.

The present application describes embodiments of a radio-frequency identification (RFID) sensor based on a combinationof a surface acoustic wave (SAW) transducer and two-dimensional electron gas (2DEG) or two-dimensional hole gas (2DHG)conducting structure, and its use in chemical detection and (bio)molecular diagnostics. The SAW RFID sensor chip contains apiezoelectric substrate, on which a multilayer heterojunction structure is deposited. The heterojunction structure comprises atleast two layers, a buffer layer and a barrier layer, wherein both layers are grown from III-V single-crystalline or polycrystallinesemiconductor materials, such as Ga N/Al Ga N. Interdigitated transducers (IDTs) transducing SAWs are installed on top of thebarrier layer. A 2DEG or 2DHG conducting channel is formed at the interface between the buffer and barrier layers and provideselectron or hole current in the system between the non-ohmic (capacitively-coupled) source and drain contacts connected to theformed channel.

The present application describes embodiments of a zero-power radio-frequency identification (RFID) sensor chip based on a combination of a surface acoustic wave (SAW) transducer and two-dimensional electron gas (2DEG) or two-dimensional holegas (2DHG) conducting structure, and its use as an ultrasensitive microphone for material and structure sensing. The SAW RFID sensor contains a piezoelectric substrate, on which a multilayer heterojunction structure is deposited. The heterojunction structure comprises at least two layers, a buffer layer and a barrier layer, wherein both layers are grown from III-V single-crystalline or polycrystalline semiconductor materials, such as Ga N/Al Ga N. Interdigitated transducers (IDTs) transducing SAWs are installed on top of the barrier layer. A conducting channel comprising a two-dimensional electron gas (2DEG), in case of two-layers configuration, or a two-dimensional hole gas (2DHG), in case of three-layers configuration, is formed at the interface between the buffer and barrier layers and provides electron or hole current in the system between the non-ohmic (capacitively-coupled) source and drain contacts connected to the formed channel.

A package that includes an integrated device, an integrated passive device and a void. The integrated device is configured as a filter. The integrated device includes a substrate comprising a piezoelectric material, and at least one metal layer coupled to a first surface of the first substrate. The integrated passive device is coupled to the integrated device. The integrated passive device is configured as a cap for the integrated device. The void is located between the integrated device and the integrated passive device.

The invention relates to an RF filter with reduced insertion loss. The filter (F) includes a first bandpass filter (BPF1) having a passband, a circuit unit (SE) having an undesired excitation at a critical frequency (f.sub.s) and a reflector (R) that reflects RF signals of this frequency before the circuit unit is undesirably excited and the power is lost as a result.

For a reactance filter constructed from serial and parallel resonators, in order to improve the linearity, it is proposed to connect a capacitor in series or in parallel either with a parallel resonator or a cascade of parallel resonators or with a series resonator or a cascade of series resonators.