Panasonic Corporation

Skyworks Filter Solutions Japan Co., Ltd.

Panasonic Intellectual Property Management Co., Ltd.

Shoji Okamoto

Hiroyuki Nakamura

Masahiro Yasumi

Hidekazu Nakanishi

Tomohiro Iwasaki

Yosuke Hamaoka

Toru Yamaji

Mitsunori Miyanari

Takashi Inoue

Toru Jibu

Hiroki Kamiguchi

Michihiko Hayashi

Rei Goto

Takahiro Sato

Satoshi Ohuchi

Shun-ichi Seki

Hidehito Shimizu

Yuuki Nakamura

A surface acoustic wave device comprises a substrate and an interdigital transducer (IDT) electrode disposed on the substrate. The IDT electrode includes a lower electrode layer having a lower surface in contact with an upper surface of the substrate and an upper electrode layer having a lower surface defining a base in contact with an upper surface of the lower electrode layer. Side surfaces of the lower electrode layer are substantially perpendicular to the upper surface of the substrate. Side surfaces of the upper electrode layer are disposed at an acute angle relative to the upper surface of the substrate.

Acoustic wave device including multi-layer interdigital transducer electrodes

An acoustic wave device comprises an IDT electrode disposed above an upper surface of a piezoelectric substrate and includes a plurality of electrode fingers configured to excite a main acoustic wave. A first dielectric film made of an oxide is disposed above the upper surface of the piezoelectric substrate and covers the plurality of electrode fingers. A second dielectric film made of non-oxide is disposed between the first dielectric film and each of the plurality of electrode fingers. A third dielectric film is disposed between the piezoelectric substrate and the plurality of electrode fingers. A speed of a transverse wave propagating through the third dielectric film is greater than a speed of the main acoustic wave propagating through the piezoelectric substrate. The third dielectric film contacts the first dielectric film between adjacent electrode fingers of the plurality of electrode fingers.

Acoustic wave device including multiple dielectric films

An acoustic wave device includes a piezoelectric substrate, an IDT electrode including plural electrode fingers disposed above an upper surface of the piezoelectric substrate, a first dielectric film made of oxide disposed above the upper surface of the substrate for covering the electrode fingers, and a second dielectric film made of non-oxide disposed on upper surfaces of the electrode fingers and between the first dielectric film and each of the electrode fingers. The first dielectric film contacts the upper surface of the piezoelectric substrate at a position between electrode fingers out of the plural electrode fingers adjacent to each other. The acoustic wave device prevents the electrode fingers of the IDT electrode from corrosion.

Acoustic wave device and electronic apparatus including same

An acoustic wave device includes an interdigital transducer (IDT) electrode and a separate electrode facing the IDT electrode. The IDT electrode includes first and second comb-shaped electrode facing each other. The first comb-shaped electrode includes a first bus bar, first interdigitated electrode fingers, and first dummy electrode fingers. The second comb-shaped electrode includes a second bus bar second interdigitated electrode fingers interdigitated with the first interdigitated electrode fingers, second dummy electrode fingers facing the first interdigitated electrode fingers, weighted parts, and a non-weighted part. The weighted parts have electrodes at spaces between the second interdigitated electrode fingers and the second dummy electrode fingers. In the non-weighted part, there is no electrode at a space out of the spaces which is closest to the separate electrode in the non-interdigitated region. This acoustic wave device prevents short circuits between the IDT electrode and the separate electrode, and provides excellent characteristics of suppressing unwanted waves.

Acoustic wave device and acoustic wave filter

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 device includes a piezoelectric substrate, an interdigital transducer (IDT) electrode, a reflector electrode, and a dummy electrode. The IDT electrode includes electrode fingers extending in a predetermined direction. The reflector electrode faces the IDT electrode across a gap. The dummy electrode is situated on a straight line extending in the predetermined direction through the gap. At least one of the distance between the dummy electrode and the IDT electrode and the distance between the dummy electrode and the reflector electrode is larger than the distance between the IDT electrode and the reflector electrode. This acoustic wave device prevents a short circuit between the IDT electrode and the reflector electrode, thereby avoiding a decrease in its yield.

Acoustic wave device

A SAW filter includes a piezoelectric body, an IDT electrode on the piezoelectric body, and signal wiring electrically connected to the IDT electrode. The signal wiring has a thickness not less than a skin depth specified based on the frequency of a signal passing through the signal wiring and the electrical conductivity of the signal wiring. As a result, the signal wiring has low propagation loss of the signal passing through it, so that the SAW filter has excellent transmission characteristics.

Surface acoustic wave filter and duplexer using the same

An electronic component is disclosed, and this component includes an element with an electrode section which is formed of upper electrode (), lower electrode (), piezoelectric unit () placed between upper electrode () and lower electrode (), and adhesive layer () layered between upper electrode () and piezoelectric unit (). Piezoelectric unit () includes piezoelectric layer () made of piezoelectric material containing lead, and adhesive layer () includes a tungsten layer made of tungsten-based material. Piezoelectric layer () and the tungsten layer are layered together. The structure discussed above allows preventing a piezoelectric constant from lowering and a base-point voltage from varying. The lowering and the varying have been caused by a temperature-rise.

Electronic component and method for manufacturing the same

An upper adhesion layerformed between a piezoelectricity layerand an upper electrode layerso as to abut on the piezoelectricity layerand the upper electrode layeris included. The upper adhesion layerincludes a first tungsten layermade of tungsten in which an &#x3b1; phase and a &#x3b2; phase coexist and a second tungsten layermade of &#x3b1;-phase tungsten. The first tungsten layeris configured so as to abut on the piezoelectricity layer. It is possible to obtain a piezoelectric device which is capable of improving the adhesion property of both the piezoelectricity layer and the electrode layer and reducing a basic point voltage fluctuation at the time of high-temperature operation so as to improve reliability.

Piezoelectric device and its manufacturing method

An acoustic boundary wave device includes a piezoelectric body, an IDT layer formed on the piezoelectric body, a pad electrode layer formed on the piezoelectric body and connected to the IDT layer, a first dielectric layer formed on the piezoelectric body and covering at least a part of the IDT electrode layer, and a second dielectric layer formed on the piezoelectric body, covering the first dielectric layer, and having an opening through which at least a part of a top face of the pad electrode layer is exposed. The metal forming lateral faces of the pad electrode layer diffuses more readily into the first dielectric layer than into the second dielectric layer. The second dielectric layer covers the lateral faces of the pad electrode layer and prevents the first dielectric layer from touching the lateral faces of the pad electrode layer.

Growing community of inventors

Osaka, Japan

Shoji Okamoto