Patent application number | Description | Published |
20110133600 | ELASTIC WAVE DEVICE - An elastic wave device has a low temperature coefficient of frequency (TCF), a low insertion loss, a high electromechanical coupling coefficient (k | 06-09-2011 |
20110241481 | SURFACE ACOUSTIC WAVE DEVICE - A surface acoustic wave device has a large electromechanical coupling coefficient, a low insertion loss, and high resistance to static electricity. In the surface acoustic wave device, a piezoelectric substance includes a plurality of grooves. Each electrode finger of an IDT electrode includes a first electrode layer disposed in the grooves and a second electrode layer disposed on the first electrode layer and located at a position higher than the upper opening of the grooves. In a surface acoustic wave device, the one-half power of the product of the cube of the average density (ρ | 10-06-2011 |
20120133246 | BOUNDARY ACOUSTIC WAVE DEVICE - Regarding a boundary acoustic wave device in which at least a part of an IDT electrode is embedded in a groove disposed in a piezoelectric substrate, the acoustic velocity is increased. A boundary acoustic wave device is provided with a piezoelectric substrate, a first dielectric layer, and an IDT electrode. The surface of the piezoelectric substrate is provided with a groove. The IDT electrode is disposed at the boundary between the piezoelectric substrate and the first dielectric layer in such a way that at least a part thereof is located in the groove. In the inside of the groove, the groove angle γ, which is the size of an angle formed by an upper end portion of the inside surface of the groove with the surface of the piezoelectric substrate, is less than 90 degrees. | 05-31-2012 |
20130069481 | SURFACE ACOUSTIC WAVE DEVICE - A surface acoustic wave device includes a piezoelectric substrate including a groove located in a surface thereof, an IDT electrode, and a dielectric film. The IDT electrode includes a first electrode layer located in the groove and a second electrode layer located outside the groove. The dielectric film is arranged on the piezoelectric substrate so as to cover the IDT electrode. The second electrode layer is tapered toward a side opposite to the piezoelectric substrate. | 03-21-2013 |
20130088121 | BOUNDARY ACOUSTIC WAVE DEVICE - Regarding a boundary acoustic wave device in which at least a part of an IDT electrode is embedded in a groove disposed in a piezoelectric substrate, the acoustic velocity is increased. A boundary acoustic wave device is provided with a piezoelectric substrate, a first dielectric layer, and an IDT electrode. The surface of the piezoelectric substrate is provided with a groove. The IDT electrode is disposed at the boundary between the piezoelectric substrate and the first dielectric layer in such a way that at least a part thereof is located in the groove. In the inside of the groove, the groove angle γ, which is the size of an angle formed by an upper end portion of the inside surface of the groove with the surface of the piezoelectric substrate, is less than 90 degrees. | 04-11-2013 |
20130300253 | SURFACE ACOUSTIC WAVE DEVICE - A surface acoustic wave device includes a piezoelectric substrate made of lithium niobate and including grooves in a surface thereof. Each groove includes a finger of an IDT electrode made of copper. The IDT electrode includes a first electrode layer embedded in the grooves and a second electrode layer sticking out of the surface of the piezoelectric substrate. A normalized electrode thickness of the first electrode layer is about 1.0% to about 12.0% inclusive, and the normalized electrode thickness of the second electrode layer is about 1.0% to about 9.0% inclusive. The normalized electrode thickness of the entire IDT electrode is about 6.0% to about 13.0% inclusive. | 11-14-2013 |
20130342285 | VARIABLE CAPACITANCE ELEMENT AND TUNABLE FILTER - A variable capacitance element includes a piezoelectric substrate, a buffer layer located on the piezoelectric substrate with an orientation, a dielectric layer located on the buffer layer and having a relative dielectric constant that varies in accordance with an applied voltage, and a first electrode and a second electrode arranged to apply an electric field to the dielectric layer. | 12-26-2013 |
20140152146 | ELASTIC WAVE DEVICE AND METHOD FOR MANUFACTURING THE SAME - An elastic wave device propagating plate waves includes a stack of an acoustic reflection layer, a piezoelectric layer, and IDT electrode on a supporting substrate. The piezoelectric layer is thinner than a period of fingers of the IDT electrode. The acoustic reflection layer includes low-acoustic-impedance layers and high-acoustic-impedance layers. The low-acoustic-impedance layers are made of SiO | 06-05-2014 |
20150061466 | ELASTIC WAVE DEVICE - An elastic wave device includes a piezoelectric substrate and an interdigital transducer electrode disposed in a piezoelectric vibrating portion of the piezoelectric substrate to pass through the piezoelectric substrate. | 03-05-2015 |