Abstract: An oscillation circuit includes a cross-coupled circuit having a first active element and a second active element which are differentially connected to each other. The oscillation circuit oscillates in a resonance frequency of a resonator connected between the first active element and the second active element.

Abstract: An oscillator circuit includes a first terminal, a second terminal, a resonator that is connected to the first terminal and the second terminal, a first capacitor that is connected to the first terminal and a ground line supplying the ground electric potential, a second capacitor that is connected to the second terminal and the ground line, m inverters, where m is an odd number equal to or larger than three, which are connected in series between the first terminal and the second terminal, and a third capacitor that is connected to an input terminal of the n-th (where n is an integer satisfying 1?n<m) inverter, counted from an input side of the inverter array and an output terminal of the (n+1)-th inverter.

Abstract: A method for manufacturing a surface acoustic wave element having an interdigital transducer (IDT) electrode formed on a semiconductor substrate includes a) forming an insulation layer on a surface of an active side of the semiconductor substrate, b) forming a base layer on a whole surface of the insulation layer, c) planarizing a surface of the base layer, d) forming a piezoelectric member on a planarized surface of the base layer, e) forming the IDT electrode on a surface of the piezoelectric member, and f) forming a bank being higher than a height from the surface of the base layer to the surface of the IDT electrode on a peripheral of the surface of the base layer so as to surround the piezoelectric member.

Abstract: A method of manufacturing a surface acoustic wave device formed in one chip and including over a semiconductor substrate at least an IC region and a surface acoustic wave element region that are horizontally disposed, the method including: forming in the IC region over the semiconductor substrate a semiconductor element layer that includes a semiconductor element and an insulation layer covering the semiconductor element and being deposited also in the surface acoustic wave element region; forming over the semiconductor element layer a wire layer that includes a plurality of wires coupled to the semiconductor element and a wire insulating film deposited over the plurality of wires to provide insulation among the wires, the wire insulating film being deposited also over the insulation layer in the surface acoustic wave element region; forming an interlayer insulating film having a flattened surface on the wire insulating film in the IC region and the surface acoustic wave element region; forming a piezoelectri

Abstract: A surface acoustic wave oscillator includes: a cross-coupled circuit including first and second active elements differentially connected to first and second output terminals; first and second surface acoustic wave elements having different resonance frequencies and connected to the cross-coupled circuit in parallel; a first variable capacitance circuit including a first variable capacitance element and changing the resonance frequency of the first surface acoustic wave element; and a second variable capacitance circuit including a second variable capacitance element and changing the resonance frequency of the second surface acoustic wave element, wherein the first surface acoustic wave element is connected to the first variable capacitance circuit, the second surface acoustic wave element is connected to the second variable capacitance circuit, and oscillating outputs from combining outputs of the first and second surface acoustic wave elements are outputted by the cross-coupled circuit.

Abstract: A method for manufacturing a surface acoustic wave element having an interdigital transducer (IDT) electrode formed on a semiconductor substrate includes a) forming an insulation layer on a surface of an active side of the semiconductor substrate, b) forming a base layer on a whole surface of the insulation layer, c) planarizing a surface of the base layer, d) forming a piezoelectric member on a planarized surface of the base layer, e) forming the IDT electrode on a surface of the piezoelectric member, and f) forming a bank being higher than a height from the surface of the base layer to the surface of the IDT electrode on a peripheral of the surface of the base layer so as to surround the piezoelectric member.

Abstract: A method of manufacturing a surface acoustic wave device formed in one chip and including over a semiconductor substrate at least an IC region and a surface acoustic wave element region that are horizontally disposed, the method including: forming in the IC region over the semiconductor substrate a semiconductor element layer that includes a semiconductor element and an insulation layer covering the semiconductor element and being deposited also in the surface acoustic wave element region; forming over the semiconductor element layer a wire layer that includes a plurality of wires coupled to the semiconductor element and a wire insulating film deposited over the plurality of wires to provide insulation among the wires, the wire insulating film being deposited also over the insulation layer in the surface acoustic wave element region; forming an interlayer insulating film having a flattened surface on the wire insulating film in the IC region and the surface acoustic wave element region; forming a piezoelectri

Abstract: A high-frequency module is provided that includes a reception portion that processes a reception signal received by a reception antenna, and a transmission portion that processes a transmission signal to be supplied to a transmission antenna. The reception portion includes a demultiplexer circuit that divides a reception signal received at the reception antenna to two reception lines having different frequency bands from each other. The transmission portion includes power amplifier circuits and a demultiplexer circuit. The high-frequency module is configured so that the demultiplexer circuit and the like included in the reception portion, as well as the power amplifier circuits and the demultiplexer circuit included in the transmission portion, are provided inside a multi-layer substrate.

Abstract: A high-frequency composite component is provided by placing an antenna on a multi-layer wiring board, placing a multiplexer/demultiplexer circuit, first and second matching circuits, and first and second balanced-to-unbalanced transformer circuits inside the board respectively, and providing first to fourth input and output terminals on the side surface of the board. The antenna is connected to the multiplexer/demultiplexer circuit via a first unbalanced line path, and the multiplexer/demultiplexer is connected to the first and second matching circuits via second and third unbalanced line paths, respectively. The first and second matching circuits are connected to the first and second balanced-to-unbalanced transformer circuits, respectively, via fourth and fifth unbalanced line paths, respectively.