Abstract: A surface acoustic wave device has high power withstanding performance and is able to effectively suppress an undesirable spurious response. The surface acoustic wave device includes an LiNbO3 substrate having Euler angles (0°±5°, ?±5°, 0°±10°), an electrode that is disposed on the LiNbO3 substrate and that has an IDT electrode made mainly from Cu, a first silicon oxide film that is disposed in an area other than an area in which the electrode is disposed to have a thickness equal to that of the electrode, and a second silicon oxide film that is disposed so as to cover the electrode and the first silicon oxide film, wherein the surface acoustic wave device utilizes an SH wave, wherein a duty D of the IDT electrode is less than or equal to about 0.49, and ? of the Euler angles (0°±5°, ?±5°, 0°±10°) is set to fall within a range that satisfies the following inequality: ?10×D+92.5?100×C???37.5×D2?57.75×D+104.075+5710×C2?1105.7×C+45.

Abstract: A surface acoustic wave device has a duty that is greater than about 0.5, attenuation outside the pass band is increased, and an undesirable spurious response is effectively suppressed. The surface acoustic wave device includes an LiNbO3 substrate having Euler angles (0°±5°, ?±5°, 0°±10°), an electrode that is provided on the LiNbO3 substrate and that includes an IDT electrode primarily made of Cu, a first silicon oxide film that is provided in an area other than an area in which the electrode is arranged so as to have a thickness substantially equal to that of the electrode, and a second silicon oxide film that is arranged so as to cover the electrode and the first silicon oxide film, wherein the surface acoustic wave device utilizes an SH wave, wherein a duty D of the IDT electrode 3 is at least about 0.52, and ? of the Euler angles (0°±5, ?+5°, 0°±10°) is set so as to fall within a range that satisfies the following Inequality (1A) or (1B): (1) When 0.52?D?0.6, ?10×D+92.5?100×C???37.5×D2?57.75×D+104.

Abstract: A surface acoustic wave device utilizing a Rayleigh wave includes a LiNbO3 substrate having Euler angles of (0°±5°, ?±5°, 0°±10°), an electrode which is disposed on the LiNbO3 substrate and which includes an IDT electrode primarily including Cu, a first silicon oxide film disposed in a region other than the region in which the electrode is disposed, the first silicon oxide film having a film thickness substantially equal to the thickness of the electrode, and a second silicon oxide film arranged to cover the electrode and the first silicon oxide film, wherein the film thickness of the electrode is within the range of about 0.12? to about 0.18?, where ? represents the wavelength of a surface acoustic wave, and ? of the above-described Euler angles of (0°±5°, ?±5°, 0°±10°) is in the range satisfying the following Formula (1): ?=32.01?351.92×exp(?Tcu/0.0187)??Formula (1) where Tcu is a value of Cu electrode film thickness normalized with the wavelength ?.

Abstract: A surface acoustic wave device utilizing a Rayleigh wave includes a LiNbO3 substrate having Euler angles of (0°±5°, 0±5°, 0°±10°), an electrode which is disposed on the LiNbO3 substrate and which includes an IDT electrode primarily including Au, a first silicon oxide film disposed in a region other than the region in which the above-described electrode is disposed, the first silicon oxide film having a film thickness substantially equal to the thickness of the above-described electrode, and a second silicon oxide film arranged to cover the electrode and the first silicon oxide film, wherein the film thickness of the electrode is in the range of about 0.062? to about 0.14?, where ? represents the wavelength of a surface acoustic wave, and ? of the above-described Euler angles of (0°±5°, 0±5°, 0°±10°) is in the range satisfying the following Formula (1): ?=31.72?206.92×exp (?1×TAu/0.0138) ??Formula (1) where TAu is a value of Au electrode film thickness normalized with the wavelength ?.

Abstract: In an acoustic wave resonator, an IDT electrode is provided on a piezoelectric substrate. The IDT electrode is apodization-weighted such that a plurality of maximum values of cross widths are provided in acoustic wave propagation directions. Alternatively, in apodization weighting, weighting is applied such that at least one of a pair of envelopes located at outer side portions of the IDT electrode in directions substantially perpendicular to acoustic wave propagation directions includes a plurality of angled envelope portions angled from a central portion of the IDT electrode toward an outer side portion of the IDT electrode in a direction substantially perpendicular to the acoustic wave propagation directions.

Abstract: A surface acoustic wave device includes a LiNbO3 substrate having Euler angles (0°±5°, ?, 0°±10°), electrodes that are disposed on the LiNbO3 substrate, are primarily composed of Cu, and include an IDT electrode, a first silicon oxide film having substantially the same thickness as the electrodes and disposed in an area other than an area on which the electrodes including the IDT electrode are disposed, and a second silicon oxide film disposed on the electrodes and the first silicon oxide film, wherein the Euler angle ? and the normalized thickness H of the second silicon oxide film are selected to satisfy the formula 1 or 2: ?50×H2?3.5×H+38.275?{?}?10H+35 (wherein H<0.25)??Formula 1 ?50×H2?3.5×H+38.275?{?}?37.5 (wherein H>0.25)??Formula 2.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, at least one interdigital transducer (IDT) electrode provided on the piezoelectric substrate, and an insulator layer to improve a temperature characteristic arranged so as to cover the IDT electrode. When a surface of the insulator layer is classified into a first surface region under which the IDT electrode is positioned and a second surface region under which no IDT electrode is positioned, the surface of the insulator layer in at least one portion of the second surface region is higher than the surface of the insulator layer from the piezoelectric substrate in at least one portion of the first surface region by at least about 0.001?, where the wavelength of an acoustic wave is ?.

Abstract: In a manufacturing method for a SAW apparatus a first insulating layer is formed on the entire surface of a piezoelectric LiTaO3 substrate. By using a resist pattern used for forming an IDT electrode, the first insulating layer in which the IDT electrode is to be formed is removed. An electrode film made of a metal having a density higher than Al or an alloy primarily including such a metal is disposed in the area in which the first insulating layer is removed so as to form the IDT electrode. The resist pattern remaining on the first insulating layer is removed. A second insulating layer is formed to cover the first insulating layer and the IDT electrode.

Abstract: In a manufacturing method for a SAW apparatus a first insulating layer is formed on the entire surface of a piezoelectric LiTaO3 substrate. By using a resist pattern used for forming an IDT electrode, the first insulating layer in which the IDT electrode is to be formed is removed. An electrode film made of a metal having a density higher than Al or an alloy primarily including such a metal is disposed in the area in which the first insulating layer is removed so as to form the IDT electrode. The resist pattern remaining on the first insulating layer is removed. A second insulating layer is formed to cover the first insulating layer and the IDT electrode.

Abstract: A surface acoustic wave device includes a piezoelectric substrate made of LiTaO3 or LiNbO3 having an electromechanical coefficient of about 15% or more, at least one electrode which is disposed on the piezoelectric substrate and which is a laminate film having a metal layer defining a primary metal layer primarily composed of a metal having a density higher than that of Al or an alloy of the metal and a metal layer which is laminated on the primary metal layer and which is composed of another metal, and a first SiO2 layer which is disposed in a remaining area other than that at which the at least one electrode is located and which has a thickness approximately equivalent to that of the electrode. In the surface acoustic wave device described above, the density of the electrode is at least about 1.5 times that of the first SiO2 layer.

Abstract: In a surface acoustic wave device, electrode films constituting at least one IDT are disposed on a piezoelectric substrate, and an SiO2 film is arranged on the piezoelectric substrate so as to cover the electrode films. The film-thickness of the electrode films is in the range of about 1% to about 3% of the wavelength of an excited surface acoustic wave.

Abstract: A surface acoustic wave device includes a piezoelectric substrate made of LiNbO3 having an electromechanical coupling coefficient k whose square is at least about 0.025, at least one electrode that is made of a metal whose density is greater than that of Al or an alloy primarily including the metal or that is composed of laminated films made of a metal whose density is greater than that of Al or an alloy primarily including the metal and another metal, the electrode being disposed on the piezoelectric substrate, a first insulating layer disposed in a region other than a region where the at least one electrode is disposed, the thickness of the first insulating layer being substantially equal to that of the electrode, and a second insulating layer covering the electrode and the first insulating layer. The density of the electrode is at least about 1.5 times greater than that of the first insulating layer.

Abstract: A surface acoustic wave device includes a piezoelectric substrate made of LiTaO3 or LiNbO3 having an electromechanical coefficient of about 15% or more, at least one electrode which is disposed on the piezoelectric substrate and which is a laminate film having a metal layer defining a primary metal layer primarily composed of a metal having a density higher than that of Al or an alloy of the metal and a metal layer which is laminated on the primary metal layer and which is composed of another metal, and a first SiO2 layer which is disposed in a remaining area other than that at which the at least one electrode is located and which has a thickness approximately equivalent to that of the electrode. In the surface acoustic wave device described above, the density of the electrode is at least about 1.5 times that of the first SiO2 layer.

Abstract: An optical pickup has a first compatible objective and a second compatible objective, the first objective having a diffractive lens structure capable of recording and playback to and from CD and HD DVD, the second objective having a diffractive lens structure capable of recording and playback to and from both DVD and BD. The first objective has the diffractive lens structure that meets the condition of 0.75?(?1×m1)/(?3×m3)?0.99, where m1 and m3 are diffraction orders of diffracted lights used to read and write CD and HD DVD. The second objective has the diffractive lens structure that meets the condition of 0.75?(?4×m4)/(?2×m2)?0.99, where m2 and m4 are diffraction orders of diffracted lights used to read and write DVD and BD.

Abstract: In a manufacturing method for a SAW apparatus a first insulating layer is formed on the entire surface of a piezoelectric LiTaO3 substrate. By using a resist pattern used for forming an IDT electrode, the first insulating layer in which the IDT electrode is to be formed is removed. An electrode film made of a metal having a density higher than Al or an alloy primarily including such a metal is disposed in the area in which the first insulating layer is removed so as to form the IDT electrode. The resist pattern remaining on the first insulating layer is removed. A second insulating layer is formed to cover the first insulating layer and the IDT electrode.

Abstract: In a manufacturing method for a SAW apparatus a first insulating layer is formed on the entire surface of a piezoelectric LiTaO3 substrate. By using a resist pattern used for forming an IDT electrode, the first insulating layer in which the IDT electrode is to be formed is removed. An electrode film made of a metal having a density higher than Al or an alloy primarily including such a metal is disposed in the area in which the first insulating layer is removed so as to form the IDT electrode. The resist pattern remaining on the first insulating layer is removed. A second insulating layer is formed to cover the first insulating layer and the IDT electrode.

Abstract: In a surface acoustic wave device, electrode films constituting at least one IDT are disposed on a piezoelectric substrate, and an SiO2 film is arranged on the piezoelectric substrate so as to cover the electrode films. The film-thickness of the electrode films is in the range of about 1% to about 3% of the wavelength of an excited surface acoustic wave.

Abstract: In a manufacturing method for a SAW apparatus a first insulating layer is formed on the entire surface of a piezoelectric LiTaO3 substrate. By using a resist pattern used for forming an IDT electrode, the first insulating layer in which the IDT electrode is to be formed is removed. An electrode film made of a metal having a density higher than Al or an alloy primarily including such a metal is disposed in the area in which the first insulating layer is removed so as to form the IDT electrode. The resist pattern remaining on the first insulating layer is removed. A second insulating layer is formed to cover the first insulating layer and the IDT electrode.

Abstract: A surface acoustic wave device includes a piezoelectric substrate and interdigital electrodes disposed on the piezoelectric substrate, wherein each of the interdigital electrodes includes a main electrode layer made of Cu or an alloy that has Cu as its main component. The surface acoustic wave device also includes a tightly adhering layer which is disposed between the main electrode layer and the piezoelectric substrate and whose main component is NiCr, or a tightly adhering layer whose main component is Ti and whose film thickness is within a range of about 18 nm to about 60 nm.

Abstract: A surface acoustic wave device includes a piezoelectric substrate made of LiNbO3 having an electromechanical coupling coefficient k whose square is at least about 0.025, at least one electrode that is made of a metal whose density is greater than that of Al or an alloy primarily including the metal or that is composed of laminated films made of a metal whose density is greater than that of Al or an alloy primarily including the metal and another metal, the electrode being disposed on the piezoelectric substrate, a first insulating layer disposed in a region other than a region where the at least one electrode is disposed, the thickness of the first insulating layer being substantially equal to that of the electrode, and a second insulating layer covering the electrode and the first insulating layer. The density of the electrode is at least about 1.5 times greater than that of the first insulating layer.