Matsushita Electric Industrial Co., Ltd.

Panasonic Corporation

Shun-ichi Seki

Keiji Onishi

Kazuo Eda

Yutaka Taguchi

Osamu Kawasaki

Hiroyuki Nakamura

Hiroki Sato

Yoshihiro Bessho

Hidekazu Nakanishi

Hideki Iwaki

Tsukasa Shiraishi

Takashi Inoue

Toru Yamada

Akihiko Namba

Shoji Okamoto

Hiroki Kamiguchi

Tsutomu Igaki

Kazuo Ikeda

Tetsuyosi Ogura

Yosihiro Tomita

An acoustic wave device includes a piezoelectric substrate, an IDT electrode provided on the piezoelectric substrate, a dielectric layer provided so as to cover the IDT electrode, and a first stress relaxation layer provided on the dielectric layer. Furthermore, the acoustic wave device includes an extraction electrode connected to the IDT electrode and extracted onto the first stress relaxation layer, and a bump provided on the extraction electrode. An elastic modulus of the first stress relaxation layer is smaller than that of the dielectric layer.

Acoustic wave device, and filter and duplexer using the same

An acoustic wave element includes a piezoelectric body, first and second interdigital transducer (IDT) electrodes provided on an upper surface of the piezoelectric body, and a first dielectric layer provided on the upper surface of the piezoelectric body to cover the first and second IDT electrodes. The first dielectric layer has a first part directly above the first IDT electrode and a second part directly above the second IDT electrode. The height of an upper surface of the second part of the first dielectric layer is larger than the height of an upper surface of the first part of the first dielectric layer. This acoustic wave element has a preferable temperature characteristic and electromechanical coupling factor.

Elastic wave element and electronic apparatus using same

A Q-factor of a resonator at a high frequency is improved. An insertion loss of a filter using such a resonator and steepness of the filter are improved. A plurality of surface acoustic wave resonators including an interdigital transducer and reflecting electrodes provided on both sides thereof are connected in parallel on a piezoelectric substrate. Resonance frequencies of the surface acoustic wave resonators are rendered equal among all the resonators connected in parallel. In this way, the Q-factor of the resonance can be improved. A surface acoustic wave filter using such surface acoustic wave resonators is formed in order to improve the insertion loss and the steepness.

Surface acoustic wave resonator and surface acoustic wave filter using the same

A band elimination filter includes an input terminal and an output terminal. A capacitor is coupled between a first terminal connected to the input terminal and a second terminal connected to the output terminal. The first terminal is grounded only via a first grounding point. The second terminal is grounded only via a second grounding point. A first acoustic resonator is connected between the first terminal and the first grounding point and a second acoustic resonator is connected between the second terminal and the second grounding point.

Band elimination filter, filter device, antenna duplexer and communication apparatus

An antenna duplexer including: a transmission filter, a reception filter, phase-shift circuits of adjusting phase characteristics on a transmission side and a reception side; and a junction point of connecting an antenna, wherein (1) an absolute value &#x3b8;of a difference between a first phase at a predetermined frequency of a pass band of the first filter and a second phase at the predetermined frequency at the time when the reception filter side is viewed from the junction point and (2) an absolute value &#x3b8;of a difference between a third phase at a predetermined frequency of a pass band of the reception filter and a fourth phase at the predetermined frequency at the time when the transmission filter side is viewed from the junction point is included in a range of 100 degrees or more and 170 degrees or less.

Antenna duplexer, design method for antenna duplexer, production method for antenna duplexer, and communication apparatus using the same

The present invention provides a surface acoustic wave filter and others that reduce ripples in a reception frequency band while ensuring sufficient attenuation in a transmission frequency band. A surface acoustic wave filter includes a surface acoustic wave resonator that allows a reception frequency band to pass while attenuating a transmission frequency band, and a surface acoustic wave filter connected in series with the surface acoustic wave resonator to allow the reception frequency band to pass while attenuating the transmission frequency band. An inductor is connected to one end of the surface acoustic wave resonator, a connection point between the surface acoustic wave filter and the surface acoustic wave resonator, and/or the other end of the surface acoustic wave resonator.

Surface acoustic wave filter, and antenna duplexer and communication equipment using the same

A resonator ladder type surface acoustic wave filter, has an input electrical terminal, an output electrical terminal, and a grounding terminal being formed on a piezoelectric substrate, a series arm surface acoustic wave resonator and a parallel arm surface acoustic wave resonator, each constructed from an interdigital transducer for exciting a surface acoustic wave, being formed between said input electrical terminal and said output electrical terminal, and when the center frequency of said resonator ladder type surface acoustic wave filter is denoted by fc, and capacitance determined by the number of electrode finger pairs and electrode finger overlap width in said interdigital transducer of said parallel arm surface acoustic wave resonator is denoted by Cp (fc: center frequency [GHz], Cp: capacitance of the interdigital transducer of the parallel arm surface acoustic wave resonator), capacitance C of multiples of said parallel arm surface acoustic wave resonator, connected to the same node between said input electrical terminal and said output electrical terminal, always satisfies the relation

Resonator ladder type surface acoustic wave filter

The present invention relates to an electronic part used for mobile communications apparatuses and the like, and more particularly to an electronic part, such as an acoustic surface-wave device, a piezoelectric ceramic device or the like, which requires an oscillation space near the surface of the functional device chip thereof, and a method of production thereof. With this method, a space retainer for forming a sealed space at the functional portion of the chip can be hermetically sealed and have high moisture resistance, and the process of forming the space retainer can be carried out easily. The electronic part of the present invention comprises a functional device chip, a space retainer for forming a sealed space at the functional portion of the chip, a circuit substrate to which the chip is secured, electrode interconnection portions for establishing electric connection between the chip and the circuit substrate, and a sealing resin for covering and sealing at least the space retainer, wherein the space retainer comprises a support layer made of a synthetic resin film, provided with an opening enclosing the functional portion and joined onto the main surface, and a cover formed and joined onto the support layer so as to cover the functional portion and form a sealed space between the cover and the functional portion.

Electronic part and a method of production thereof

The filter circuit is a filter circuit having plural passbands including a first filter having a first passband, and a second filter having a second passband, with their inputs and outputs connected mutually so that these filters are connected in parallel. Inductor elements are connected in series to the terminal of the first filter to which the second filter is connected, and capacitor elements are connected in series to the terminal of the second filter to which the first filter is connected.

Filter circuit having plural passing bands

A surface acoustic wave device has a main substrate; a comb-like electrode formed on one of the main surfaces of said main substrate; and a supplementary substrate joined with the other main surface of said main substrate, wherein said supplementary substrate has a smaller thermal expansion coefficient and a larger thickness than said main substrate.

Surface acoustic wave devices and their manufacturing method

A compact, low height, low cost, and high reliability surface acoustic wave device, and its method of manufacture. The surface acoustic wave device consists of a substrate, a comb-electrode disposed on the main surface of the substrate, plural electrode pads disposed around the comb-electrode, protecting means covering the comb-electrode through a closed space produced by combining the comb-electrode and the electrode pads with the substrate by using substantially covalent bonding force acting between conductive bumps formed on the electrode bumps, a conductive adhesive layer disposed at least on the top of the conductive bumps, and a package adhered on the conductive bumps by means of the conductive adhesive, and insulation adhesive filled into the package contacting the conductive adhesive, the conductive bumps, and the protective means.

Method of manufacture of surface acoustic wave device

36.degree. -rotated Y-cut X-propagation lithium niobate substrate (LiNbO.sub.3) was used as a piezoelectric substrate to compose a surface acoustic wave filter and is connected with a dielectric filter in series. The dielectric filter having a sign of the frequency temperature characteristic which is opposite to that of the surface acoustic wave filter was used. Accordingly, a high frequency filter, comprising a surface acoustic filter and a dielectric filter connected in series, which can secure sufficient attenuation without an increase in the insertion loss within the band can be provided.

High frequency filter having saw and dielectric filters with different

A balanced-type surface acoustic wave filter is provided which can attain a balanced-type of high frequency circuit without connecting a balance-unbalanced conversion circuit. A substrate of tantalic acid lithium substrate with 36 degrees rotation, Y cut, and X propagation is used, and aluminium is used for electrode to form resonators. Then, two resonators in a serial arm and two resonators in a parallel arm are connected in the form of symmetry and lattice to form a balanced-type surface acoustic wave filter. In this configuration, antiresonance frequency in the serial arms and resonance frequency in the parallel arms are substantially equal to each other.

Balanced-type surface acoustic wave lattice filter

A compact, low height, low cost, and high reliability surface acoustic wave device, and its method of manufacture. The surface acoustic wave device consists of a substrate, a comb-electrode disposed on the main surface of the substrate, plural electrode pads disposed around the comb-electrode, protecting means covering the comb-electrode through a closed space produced by combining the comb-electrode and the electrode pads with the substrate by using substantially covalent bonding force acting between conductive bumps formed on the electrode bumps, a conductive adhesive layer disposed at least on the top of the conductive bumps, and a package adhered on the conductive bumps by means of the conductive adhesive, and insulation adhesive filled into the package contacting the conductive adhesive, the conductive bumps and the protective means.

Growing community of inventors

Hyogo, Japan

Shun-ichi Seki