| Patent application number | Description | Published |
|---|
| 20080315973 | SURFACE ACOUSTIC WAVE FILTER, BOUNDARY ACOUSTIC WAVE FILTER, AND ANTENNA DUPLEXER USING SAME - A surface acoustic wave filter includes a piezoelectric substrate including lithium niobate, a series resonator including a first interdigital transducer electrode provided on the piezoelectric substrate, and a parallel resonator including a second interdigital transducer electrode provided on the piezoelectric substrate and being electrically connected to the series resonator. An apodized weighting factor of the first interdigital transducer electrode is smaller than an apodized weighting factor of the second interdigital transducer electrode. This surface acoustic wave filter has a small loss. | 12-25-2008 |
| 20090267447 | ACOUSTIC WAVE DEVICE - An acoustic wave device includes a piezoelectric substrate having a surface adapted to allow leaky surface wave to propagate thereon, an interdigital electrode provided on a portion of the surface of the piezoelectric substrate, and a dielectric layer provided on the surface of the piezoelectric substrate to cover the interdigital electrode. The piezoelectric substrate is made of lithium niobate. The dielectric layer is made of tantalum pentoxide. The piezoelectric substrate is made of a rotated Y-cut substrate having a cut angle which is not smaller than 2.5 degrees and is not larger than 22.5 degrees. A ratio H/λ of a film thickness H of the dielectric layer to a wavelength λ of a center frequency of the leaky surface wave ranges from 0.034 to 0.126. This acoustic wave device works in a wide band width. | 10-29-2009 |
| 20090267449 | ELASTIC WAVE DEVICE AND FILTER AND ELECTRONIC EQUIPMENT USING THE DEVICE - The elastic wave device of the present invention has an piezoelectric substrate; a first dielectric layer disposed on the piezoelectric substrate; a second dielectric layer disposed on the first dielectric layer; and an acoustical layer on the second dielectric layer. Determining each film thickness of the first and the second dielectric layers provides advantageous effects. That is, energy of an SH wave as a main wave is confined in the boundary between the piezoelectric substrate and the first dielectric layer, and at the same time, an SV wave is suppressed as an unwanted wave. The device allows the SV wave—whose displacement distribution is similar to that of Stoneley wave—to have displacement distribution on the upper surface of the second dielectric layer and to be suppressed by the acoustical layer disposed on the second dielectric layer. | 10-29-2009 |
| 20100060102 | ACOUSTIC WAVE DEVICE AND ELECTRONIC EQUIPMENT USING THE SAME - An acoustic wave device has: a piezoelectric body; an interdigital electrode that is arranged on the piezoelectric body and excites an acoustic wave; and a dielectric layer that is arranged on the piezoelectric body so as to cover the interdigital electrode. The dielectric layer includes a composition changing portion made up of a medium where propagation velocity of a transverse wave continuously increases upward. With this configuration, it is possible to shift a spurious radiation by a high-order mode that propagates inside the dielectric layer to a higher frequency, so as to reduce an influence of the spurious radiation by the high-order mode. | 03-11-2010 |
| 20100060103 | SURFACE ACOUSTIC WAVE RESONATOR - A surface acoustic wave resonator of the present invention includes a piezoelectric substrate ( | 03-11-2010 |
| 20100127597 | ACOUSTIC BOUNDARY WAVE DEVICE AND ELECTRONIC APPARATUS USING THE SAME - 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. | 05-27-2010 |
| 20100164646 | SURFACE ACOUSTIC WAVE DEVICE, SURFACE ACOUSTIC WAVE FILTER AND ANTENNA DUPLEXER USING THE SAME, AND ELECTRONIC EQUIPMENT USING THE SAME - A surface acoustic wave device includes a substrate including lithium niobate; a IDT being provided on an upper surface of the substrate and including a plurality of electrode fingers; and a protective film covering the IDT and having an uneven shape on an upper surface thereof. When a pitch width of one pitch of the IDT is p, a width of one of the electrode fingers is p | 07-01-2010 |
| 20100219718 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes a first medium layer made of piezoelectric material, a second medium layer provided on the first medium layer, a third medium layer provided on the second medium layer, and an electrode provided at an interface between the second and third medium layers. The electrode drives the third medium layer to generate a transverse wave. A propagation speed of the transverse wave in the third medium layer is lower than a propagation speed of the transverse wave in the first medium layer. A propagation speed of the transverse wave in the second medium layer is lower than the propagation speed of the transverse wave in the first medium layer. This boundary acoustic wave device has a large electro-mechanical coupling coefficient. | 09-02-2010 |
| 20100219905 | SURFACE ACOUSTIC WAVE RESONATOR, AND SURFACE ACOUSTIC WAVE FILTER AND ANTENNA DUPLEXER IN WHICH THE SURFACE ACOUSTIC WAVE RESONATOR IS USED - The present invention provides a surface acoustic wave resonator capable of improving the leak of a surface acoustic wave in the transverse direction and reducing the spurious and having superior characteristics. In a surface acoustic wave filter according to the present invention, an interdigital transducer electrode and reflector electrodes are formed on a piezoelectric substrate, and a SiO | 09-02-2010 |
| 20100231089 | SURFACE ACOUSTIC WAVE DEVICE AND MANUFACTURING METHOD OF THE SAME SURFACE ACOUSTIC WAVE DEVICE - A surface acoustic wave device includes a piezoelectric element, an IDT electrode formed on the piezoelectric element for exciting a principal wave, a reflection film formed on the piezoelectric element having a higher reflectivity than the reflectivity of the piezoelectric element in a visible light wavelength region, and a light permeable dielectric layer formed on the piezoelectric element, at least a part of the IDT electrode, and the reflection film. Accordingly, when measuring the film thickness of the light permeable dielectric layer by light interference method, the reflected light from the reflection film having a higher reflectivity than the reflectivity of the piezoelectric element in a visible light wavelength region can be utilized, so that the film thickness can be measured more accurately. | 09-16-2010 |
| 20110109196 | PLATE WAVE ELEMENT AND ELECTRONIC EQUIPMENT USING SAME - A plate wave element includes a piezoelectric body, a comb-shaped electrode disposed on an upper surface of the piezoelectric body, and a medium layer disposed on the upper surface of the piezoelectric body so as to cover the comb-shaped electrode. The comb-shaped electrode excites a Lamb wave as a main wave. The medium layer has a frequency temperature characteristic opposite to that of the piezoelectric body. The plate wave element has a preferable frequency temperature characteristic. | 05-12-2011 |
| 20110133858 | ELASTIC WAVE ELEMENT AND ELECTRONIC DEVICE USING THE SAME - An elastic wave device includes a piezoelectric substrate, an IDT electrode disposed on a piezoelectric device, a first dielectric layer disposed on the piezoelectric substrate such that it covers the IDT electrode, and a second dielectric layer disposed over the first dielectric layer. The second dielectric layer propagates transverse waves faster than that on the first dielectric layer. When a film thickness of the second dielectric layer is greater than a wave length of a major wave excited by the IDT electrode, a cut angle of the piezoelectric substrate in indication of Euler angles (φ, θ, Φ) is set to φ≠0°, θ≠0°, and Φ≠0°. This suppresses deterioration of device characteristics. | 06-09-2011 |
| 20110156837 | ACOUSTIC WAVE DEVICE, AND FILTER AND DUPLEXER USING THE SAME - 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. | 06-30-2011 |
