Patent application number | Description | Published |
20080211344 | BOUNDARY ACOUSTIC WAVE DEVICE - A dielectric substance is laminated on one surface of a piezoelectric substance, and an IDT and reflectors are disposed as electrodes at a boundary between the piezoelectric substance and the dielectric substance, and the thickness of the electrodes is determined so that the acoustic velocity of the Stoneley wave is decreased less than that of a slow transverse wave propagating through the dielectric substance and that of a slow transverse wave propagating through the piezoelectric substance, thereby forming a boundary acoustic wave device. | 09-04-2008 |
20080258846 | ELASTIC WAVE FILTER - An elastic wave filter of a resonator type includes at least one IDT electrode arranged so as to contact the piezoelectric substance. The elastic wave filter is arranged such that an elastic wave in a main propagation mode for obtaining target frequency characteristics and an elastic wave in a sub-propagation mode propagate, the elastic wave being capable of propagating simultaneously with the elastic wave in the main propagation mode, an electromechanical coefficient K | 10-23-2008 |
20080290968 | BOUNDARY ACOUSTIC WAVE DEVICE AND METHOD FOR MANUFACTURING THE SAME - A boundary acoustic wave device includes a first medium, a second medium, and an IDT electrode disposed at an interface between the first medium and the second medium, the IDT electrode having an Au layer defining a main electrode layer, wherein a Ni layer is laminated so as to contact at least one surface of the Au layer, and a portion of Ni defining the Ni layer is diffused from the Ni layer side surface of the Au layer toward the inside of the Au layer. | 11-27-2008 |
20090066189 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes a first medium, a second medium, a third medium, and a fourth medium that are laminated in that order and, an electrode including an IDT electrode disposed at an interface between the first medium and the second medium, the temperature coefficient of delay time TCD of a boundary acoustic wave has a positive value, the fourth medium or the second medium has a positive temperature coefficient of sound velocity TCV, the first medium has a negative temperature coefficient of sound velocity TCV, and the sound velocity of transverse wave of the third medium is set to be less than the sound velocity of transverse wave of the fourth medium and/or the second medium. | 03-12-2009 |
20090115287 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device efficiently traps the vibrational energy of boundary acoustic waves and exhibits a high electromechanical coupling coefficient, and is consequently not affected by higher-order modes. The boundary acoustic wave device includes a first medium having piezoelectric characteristics, a non-electroconductive second medium, and a third medium through which slow transverse waves propagate at a lower acoustic velocity than slow transverse waves propagating through the first and second media. The first medium, the third medium, and the second medium are stacked in that order. An IDT is disposed between the first medium and the third medium. The IDT includes a metal layer made of a metal having a density ρ in the range of about 3000 kg/m | 05-07-2009 |
20090152993 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes a stacked structure including a second medium, an IDT electrode, and a first medium, the stacked structure including the first medium having a temperature coefficient of group delay time TCD that is positive. The IDT electrode is stacked on the first medium. The second medium is stacked on the first medium so as to cover the IDT electrode and has a temperature coefficient of group delay time TCD that is negative. A third medium having an acoustic velocity of a transverse wave that is less than an acoustic velocity of a transverse wave of the second medium is arranged at least on a top surface of the IDT electrode. | 06-18-2009 |
20090174285 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes an IDT electrode disposed at the boundary between a first medium and a second medium, the IDT electrode having electrode fingers, in which a third medium is arranged between the electrode fingers of the IDT electrode, the third medium having an acoustic impedance Z | 07-09-2009 |
20090200894 | BOUNDARY ACOUSTIC WAVE DEVICE MANUFACTURING METHOD AND BOUNDARY ACOUSTIC WAVE DEVICE - A method for manufacturing a boundary acoustic wave device includes the steps of preparing a laminated structure in which an IDT electrode is disposed at an interface between first and second solid media and reforming the first medium and/or the second medium by externally providing the laminated structure with energy capable of reaching the inside of the first medium and/or the second medium and thus adjusting a frequency of the boundary acoustic wave device. The above provides a boundary acoustic wave device manufacturing method that enables frequency adjustment to be readily performed with high accuracy. | 08-13-2009 |
20090236935 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes an IDT electrode between a piezoelectric layer and a dielectric layer. A low thermal expansion medium layer made of a material having a linear thermal expansion coefficient less than that of the piezoelectric layer is laminated on a surface of the piezoelectric layer opposite to the boundary. Acoustic velocities of transversal waves in a boundary acoustic wave propagation direction at the piezoelectric layer, the dielectric layer, and the low thermal expansion medium layer satisfy Expression (1), and when λ represents a wavelength of the IDT electrode, (an acoustic velocity of a transverse wave at the dielectric layer)/λ satisfies Expression (2) as follows: | 09-24-2009 |
20090265904 | METHOD FOR MANUFACTURING BOUNDARY ACOUSTIC WAVE DEVICE - A method for manufacturing a boundary acoustic wave device prevents formation of discontinuous portions in a dielectric film without a significant decrease in the thickness of an IDT when the dielectric film is formed by deposition and without deterioration of electrical characteristics. The method includes the steps of forming an IDT on a piezoelectric substrate, forming a lower dielectric film so as to cover the IDT, conducting a planarizing step so as to smooth the rough surface of the lower dielectric film, and forming an upper dielectric film so as to cover the lower dielectric film of which the rough surface is smoothed. | 10-29-2009 |
20090295507 | ACOUSTIC WAVE ELEMENT - An acoustic wave element includes an IDT electrode in contact with a piezoelectric material and including a plurality of electrode fingers, which include first and second electrode fingers that adjoin each other in an acoustic wave propagation direction and that connect to different potentials and a first dummy electrode finger facing the first electrode finger via a gap located on an outer side in an electrode finger length direction of the first electrode finger. At an area near the gap, first protrusions are provided in at least one of the first electrode finger and the first dummy electrode finger, the first protrusion protruding in the acoustic wave propagation direction from at least one of side edges of the at least one of the first electrode finger and the first dummy electrode finger. The acoustic wave element has greatly improved resonance characteristics of a resonance frequency and prevents short-circuit failure between electrode fingers and degradation in insulation properties. | 12-03-2009 |
20100088868 | METHOD FOR MANUFACTURING COMPOSITE PIEZOELECTRIC SUBSTRATE - A method for manufacturing a composite piezoelectric substrate is capable of forming an ultra-thin piezoelectric film having a uniform thickness by efficiently using a piezoelectric material. A piezoelectric substrate and a supporting substrate are prepared, ions are implanted from a surface of the piezoelectric substrate to form a defective layer in a region at a predetermined depth from the surface of the piezoelectric substrate, impurities that are adhered to at least one of the surface of the piezoelectric substrate in which the defective layer is formed and a surface of the supporting substrate are removed to directly expose the constituent atoms of the surfaces and to activate the surfaces, the supporting substrate is bonded to the surface of the piezoelectric substrate to form a bonded substrate body, the bonded substrate body is separated at the defective layer formed in the piezoelectric substrate so that a separation layer between the surface of the piezoelectric substrate and the defective layer is separated from the piezoelectric substrate and bonded to the supporting substrate to form a composite piezoelectric substrate, and the surface of the separation layer of the composite piezoelectric substrate is smoothed. | 04-15-2010 |
20100108248 | METHOD FOR PRODUCING PIEZOELECTRIC COMPOSITE SUBSTRATE - A method for producing a piezoelectric composite substrate having a single-crystal thin film of a piezoelectric material includes an ion-implantation step and a separation step. In the ion-implantation step, He | 05-06-2010 |
20100112233 | METHOD FOR MANUFACTURING PIEZOELECTRIC DEVICE - A lower electrode and an adhesive layer made of an insulator are formed on a back surface on the ion implantation layer side of a piezoelectric single crystal substrate. A supporting substrate in which sacrificial layers made of a conductive material have been formed is bonded to the surface of the adhesive layer. By heating the composite body including the piezoelectric single crystal substrate, the lower electrode, the adhesive layer, and the supporting substrate, a layer of the piezoelectric single crystal substrate is detached to form a piezoelectric thin film. A liquid polarizing upper electrode is formed on a detaching interface of the piezoelectric thin film. A pulsed electric field is applied using the polarizing upper electrode and the sacrificial layers as counter electrodes. Consequently, the piezoelectric thin film is polarized. | 05-06-2010 |
20100175236 | METHOD FOR MANUFACTURING PIEZOELECTRIC DEVICE - In a method for manufacturing a piezoelectric device, an ion implantation layer is formed at a desired depth from one principal surface of a piezoelectric single crystal substrate by implanting hydrogen ions into the piezoelectric single crystal substrate under desired conditions. The piezoelectric single crystal substrate in which the ion implantation layer has been formed is bonded to a supporting substrate, and THG laser light is irradiated from the supporting substrate side. Since the optical absorptance of the piezoelectric single crystal substrate to the THG laser light is higher than that of the supporting substrate, the irradiated light is absorbed primarily at the bonding surface side of the piezoelectric single crystal with the supporting substrate and heat is locally generated. With the generated heat, a piezoelectric thin film is detached from the piezoelectric single crystal substrate using the ion implantation layer as a detaching interface, and a piezoelectric composite substrate including a piezoelectric thin film and the supporting substrate is formed. | 07-15-2010 |
20120056506 | BOUNDARY ACOUSTIC WAVE DEVICE - A boundary acoustic wave device includes a first medium, a second medium laminated on the first medium, and an IDT electrode arranged at an interface between the first medium and the second medium. The boundary acoustic wave device further includes a reformed portion disposed in at least one of the first medium and the second medium, reformed by externally provided energy, and having frequency characteristics different from frequency characteristics exhibited when the boundary acoustic wave device includes only at least one of the first medium and the second medium. | 03-08-2012 |
20140173862 | METHOD FOR MANUFACTURING COMPOSITE PIEZOELECTRIC SUBSTRATE - In a method for manufacturing a composite piezoelectric substrate, a piezoelectric substrate and a supporting substrate are prepared, ions are implanted from a surface of the piezoelectric substrate to form a defective layer at a predetermined depth, impurities adhered to the surface of the piezoelectric substrate in which the defective layer is formed and/or a surface of the supporting substrate are removed to directly expose the constituent atoms of the surfaces and activate the surfaces, the supporting substrate is bonded to the piezoelectric substrate to form a bonded substrate body, the bonded substrate body is separated at the defective layer so that a separation layer between the surface of the piezoelectric substrate and the defective layer is separated from the piezoelectric substrate and bonded to the supporting substrate to form a composite piezoelectric substrate, and the surface of the separation layer of the composite piezoelectric substrate is smoothed. | 06-26-2014 |