Skyworks Filter Solutions Japan Co., Ltd.

Mitsunori Miyanari

Hiroyuki Nakamura

Toru Yamaji

Hidekazu Nakanishi

Yosuke Hamaoka

Tomohiro Iwasaki

Masahiro Yasumi

Shoji Okamoto

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

Methods and apparatus for reducing electric loss in an elastic wave element. In one example such a method includes forming an IDT electrode on a piezoelectric body, and forming the connection wiring on the piezoelectric body and electrically connecting the connection wiring to the IDT electrode. Forming the connection wiring includes sequentially forming a lower connection wiring on an upper surface of the piezoelectric body and forming an upper connection wiring over the lower connection wiring. The method further includes forming a reinforcement electrode over the connection wiring that divides the upper connection wiring into first and second upper connection wirings electrically connected to one another by the reinforcement electrode. The reinforcement electrode is formed abutting an upper surface of the lower connection wiring between the first and second upper connection wirings and electrically connected to the lower connection wiring and to the first and second upper connection wirings.

Methods of reducing electric loss in elastic wave elements

An elastic wave resonator including a pair of comb-shaped electrodes and a pair of reflector electrodes formed on a piezoelectric substrate. In one example, the pair of comb-shaped electrodes includes first and second overlapping regions in which electrode fingers of the comb-shaped electrodes interdigitate, the second overlapping region being provided on both outside edges of the first overlapping region in an overlapping width direction, an overlapping width of the first overlapping region being greater than an overlapping width of the second overlapping region, the pair of comb-shaped electrodes being configured to excite a first elastic wave in the first overlapping region and to excite a second elastic wave in the second overlapping region, a frequency of the first elastic wave being higher than a frequency of the second elastic wave.

Elastic wave resonators and filters

An elastic wave device including a substrate, an interdigital transducer (IDT) electrode provided on an upper surface of the substrate, a first wiring electrode provided on the upper surface of the substrate and connected to the IDT electrode, a dielectric film that does not cover a first region of the first wiring electrode but covers a second region of the first wiring electrode above the substrate, the first wiring electrode including a cutout in the second region, and a second wiring electrode that covers an upper surface of the first wiring electrode in the first region and an upper surface of the dielectric film in the second region above the substrate.

Acoustic wave devices having improved connection reliability

An elastic wave resonator including comb-shaped electrodes and reflector electrodes formed on a piezoelectric substrate. In one example, an overlapping portion between the comb-shaped electrodes includes a first overlapping region and second overlapping regions. The second overlapping regions can be provided on both outside edges of the first overlapping region. In one example, the overlapping width of the first overlapping region is greater than the overlapping width of the second overlapping region, and the electrode finger pitch in the second overlapping region is greater than the electrode finger pitch in the first overlapping region.

Elastic wave resonators, and elastic wave filters, antenna duplexers, modules and communication devices using same

Acoustic wave devices, and antenna duplexers, modules, and communication devices using same

Methods and apparatus for reducing electric loss in an elastic wave element. In one example, the elastic wave element includes a piezoelectric body having a upper surface, an interdigital transducer (IDT) electrode disposed on the piezoelectric body, a connection wiring disposed on the piezoelectric body and electrically connected to the IDT electrode, the connection wiring having a lower connection wiring and an upper connection wiring provided above the lower connection wiring, and a reinforcement electrode provided above the connection wiring, the reinforcement electrode being in contact with and electrically connected to the lower connection wiring.

Elastic wave element with a reinforcement electrode and ladder filter using same

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.

Growing community of inventors

Osaka-fu, Japan

Mitsunori Miyanari