Kyocera Corporation

Kazuhiro Otsuka

Tsuyoshi Nakai

Kiyohiro Iioka

Daisuke Makibuchi

Hiroyuki Tanaka

Yoshifumi Yamagata

Akira Oikawa

Mitsutaka Shimada

Masafumi Hisataka

Michihiko Kuwahata

Masaru Yamano

Motoki Ito

Junya Nishii

Atsuomi Fukuura

Ikuo Obara

A SAW device () has a substrate () configured to propagate acoustic waves; an IDT electrode () on a first main surface () of a substrate (); and an electrode pad () on the first main surface () electrically connected to the IDT electrode (). The SAW device () also has a terminal with a pillar-shape (column part ()) setted up on the electrode pad (); a third conductive layer () extending from a side surface of the column part (); and a cover () forming a vibration space (S) above the IDT electrode () and covering the side surface of the column part (), and the third conductive layer ().

Acoustic wave device and method for manufacturing same

An acoustic wave device according to one embodiment of the present invention has a base with a vibrating body, a sealing member which is joined to the base in a frame-shaped region surrounding the vibrating body and faces the vibrating body with a space therebetween, and an intermediate layer between the frame-shaped region of the sealing member and the base. The frame-shaped region has a recess and at least a portion of the intermediate layer is located inside the recess.

Acoustic wave device

A surface acoustic wave device includes front stage and rear stage surface acoustic wave elements, a signal wiring connecting between the front stage and rear stage surface acoustic wave elements, a reference potential wiring connected with the rear stage surface acoustic wave element and a capacitor made of an insulator interposed between the signal wiring and the reference potential wiring. A surface acoustic wave device includes a front stage surface acoustic wave resonator, a rear stage surface acoustic wave element, a signal wiring connecting between the front stage surface acoustic wave resonator and the rear stage surface acoustic wave element, a reference potential wiring connected with the rear stage surface acoustic wave element and a capacitor made of an insulator interposed between the signal wiring and the reference potential wiring. A communication device includes the surface acoustic wave device described above, a receiver circuit or a transmitter circuit.

Surface acoustic wave device and communication device

A surface acoustic wave elementcomprises a piezoelectric substrate, IDT electrodesof an odd number not less than three formed along a propagation direction of surface acoustic waves that propagates on the piezoelectric substrate, wherein IDT electrodesof the odd number of IDT electrodesdisposed on both sides of an IDT electrodethat is located at the center are connected to first and second reference potential terminals, respectively, and the first and second reference potential terminalsandare formed asymmetrically with respect to a virtual central axis A that passes through the center of the IDT electrodelocated at the center and provided in a direction perpendicular to the propagation direction.

Surface acoustic wave element, surface acoustic wave device and communication device including the same

A surface acoustic wave device is disclosed, which comprises a surface acoustic wave element including a lithium tantalate piezoelectric substratewith one principal surface thereof formed with an IDT electrode, a connector electrodeand a periphery sealing electrode, and a base substrateformed with an electrodefor connection to the element connected to the connector electrodethrough a solder bump componentand a periphery sealing conductor filmjoined to the periphery sealing electrodethorough a solder sealing component. For the solder bump componentand the solder sealing component, a Sn&#x2014;Sb based or Sn&#x2014;Ag based lead-free solder containing 90% or more Sn is used, and the thermal expansion coefficient of the base substrateis set in the range of 9-20 pm/&#xb0; C. The joining is accomplished with high stability resisting thermal stress due to a difference in thermal expansion coefficient, so that a surface acoustic wave device that can maintain stable connection for a long duration of time can be provided.

Method for manufacturing surface acoustic wave device

A plurality of IDT electrodestoeach having a large number of electrode fingers extending in a direction perpendicular to a propagation direction of a surface acoustic wave propagating on a piezoelectric substrateare arranged on the piezoelectric substratealong the propagation direction, and each of the two adjacent IDT electrodes out of the plurality of IDT electrodestocomprises a variable pitch section and a fixed pitch section. The electrode finger pitch in the variable pitch section gradually decreases toward the boundary between the two adjacent IDT electrodes, and the minimum electrode finger pitch portion in the two variable pitch sections is on one side spaced apart from the boundary. There can be provided a surface acoustic wave apparatus having a large pass bandwidth, having a low insertion loss, and having improved flatness in a pass band.

Surface acoustic wave resonator, surface acoustic wave device, and communications equipment

A surface acoustic wave device is disclosed, which comprises a surface acoustic wave element including a lithium tantalate piezoelectric substratewith one principal surface thereof formed with an IDT electrodea connector electrodeand a periphery sealing electrodeand a base substrateformed with an electrodefor connection to the element connected to the connector electrodethrough a solder bump componentand a periphery sealing conductor filmjoined to the periphery sealing electrodethorough a solder sealing componentFor the solder bump componentand the solder sealing componenta Sn&#x2014;Sb based or Sn&#x2014;Ag based lead-free solder containing 90% or more Sn is used, and the thermal expansion coefficient of the base substrateis set in the range of 9&#x2013;20 pm/&#xb0; C. The joining is accomplished with high stability resisting thermal stress due to a difference in thermal expansion coefficient, so that a surface acoustic wave device that can maintain stable connection for a long duration of time can be provided.

Surface acoustic wave device and method for manufacturing same

IDT electrodes are arranged on a piezoelectric substrate along a propagation direction of a surface acoustic wave whereas reflectors are each interposed between a respective pair of IDT electrodes, the reflectors each including four or more electrode fingers extended perpendicularly to the propagation direction. An electrode-finger pitch 'a' of the reflector is progressively decreased from the opposite ends of the reflector toward the center thereof. Frequencies allowed to pass through a pass band may be controlled by varying the electrode-finger pitch. Thus is provided a surface acoustic wave device featuring a wide-band transmission performance.

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Kyoto, Japan

Kazuhiro Otsuka