Abstract: A SAW device has an IDT which is provided in the principal surface of a quartz crystal substrate having Euler angles (?1.5°???1.5°, 117°???142°, |?|?90°×n (where n=0, 1, 2, 3)) and excites a Rayleigh wave (wavelength: ?) in a stopband upper end mode. Inter-electrode-finger grooves are recessed between the electrode fingers of the IDT. The depth G of the inter-electrode-finger grooves is 0.01??G?0.07?, and an electrode finger thickness H and an IDT line occupancy ? satisfy a predetermined relationship. Thus, a frequency-temperature characteristic constantly has an inflection point between a maximum value and a minimum value in an operation temperature range, thereby suppressing a fluctuation in an inflection-point temperature due to a manufacturing variation in the IDT line occupancy ?.

Abstract: A SAW device has an IDT which is provided on the principal surface of a quartz crystal substrate having Euler angles (?1.5°???1.5°, 117°???142°, 42.79?|?|?49.57°) and excites a SAW in a stopband upper end mode, and a pair of reflectors which are arranged on both sides of the IDT. Inter-electrode-finger grooves are recessed between the electrode fingers of the IDT, and inter-conductor-strip grooves are recessed between the conductor strips of the reflectors. A first direction (X? axis) perpendicular to the electrode fingers and the conductor strips intersects the electrical axis (X axis) of the quartz crystal substrate at an angle ?. At least a part of the IDT and the reflectors are arranged in a second direction intersecting the first direction at an angle ? of 1.0°???2.75°. An excellent frequency-temperature characteristic and a high Q value in an operation temperature range are realized simultaneously.

Abstract: A SAW device has an IDT which is provided on the principal surface of a quartz crystal sustrate having Euler angles (?1.5°???1.5°, 117°???42°, ?) and excites a SAW in a stopband upper end mode. Inter-electrode-finger grooves 8 are recessed between the electrode fingers of the IDT. When the Euler angle ? is 42.79°?|?|?49.57°, the thickness H of the electrode fingers of the IDT is set to be within 0.055 ?m?H?0.335 ?m, preferably, 0.080 ?m?H?0.335 ?m. When the Euler angle ? is |?|?90°×n (where n=0, 1, 2, 3), and the thickness H of the electrode fingers is set to 0.05 ?m?H?0.20 ?m.

Abstract: A SAW device 11 has an IDT which is provided on the principal surface of a quartz crystal substrate 12 having Euler angles (?1.5°???1.5°, 117°???142°, 42.79°?|?|?49.47°) and excites a SAW in a stopband upper end mode, and a pair of reflectors which are arranged on both sides of the IDT. Inter-electrode-finger grooves are recessed between the electrode fingers of the IDT, and inter-conductor-strip grooves are recessed between the conductor strips of the reflectors. The wavelength ? of the SAW and the depth G of the inter-electrode-finger grooves satisfy 0.01??G. An IDT line occupancy ? and the depth G of the inter-electrode-finger grooves satisfy a predetermined relational expression. The IDT line occupancy ? and a reflector line occupancy ?r satisfy the relationship ?<?r. Therefore, an excellent frequency-temperature characteristic and a high Q value in an operation temperature range are realized simultaneously.

Abstract: A surface acoustic wave resonator has a quartz crystal substrate having Euler angles of (?=0°, 110°???150°, 88°???92°) and an IDT having a plurality of electrode fingers disposed on the quartz crystal substrate, and using a surface acoustic wave as an excitation wave, a plurality of grooves arranged in a propagation direction of the surface acoustic wave to form stripes is disposed on the quartz crystal substrate, and the electrode fingers are disposed one of between the grooves and inside the grooves.

Abstract: A surface acoustic wave resonator includes: an IDT which is disposed on a quartz substrate with Euler angles of (?1°???1°, 117°???142°, 42.79°?|?|?49.57°, which is made of Al or alloy including Al as a main component and which excites a surface acoustic wave in an upper mode of a stop band; and an inter-electrode-finger groove which is formed by recessing the quartz substrate between electrode fingers which form the IDT. Here, the following expression is satisfied: 0.01??G??(1), where ? represents a wavelength of the surface acoustic wave and G represents a depth of the inter-electrode-finger groove. The depth G of the inter-electrode-finger groove and a line occupancy ? of the IDT satisfy the following expression: - 2.5 × G ? + 0.675 ? ? ? - 2.5 × G ? + 0.775 ( 5 ) and a number of pairs N of the electrode fingers in the IDT is in the range of the following expression: 160?N?220??(19).

Abstract: A surface acoustic wave device includes: a quartz substrate with Euler angles of (?, ?, ?); and an IDT which excites a surface acoustic wave in an upper mode of a stop band; wherein, the Euler angle ? is ?60°???60°, and the Euler angle ? determines the ranges of the Euler angles ? and ?.

Abstract: A surface acoustic wave resonator includes a piezoelectric substrate and an interdigital transducer (IDT) that includes electrode fingers exciting a surface acoustic wave on the piezoelectric substrate, a first region at a center of the IDT, and a second region and a third region at opposite sides of the IDT. In the IDT, a line occupation rate at which an electromechanical coupling coefficient becomes a maximum is different from the line occupation rate at which reflection of the surface acoustic wave becomes a maximum.

Abstract: A surface acoustic wave (SAW) resonator and a SAW oscillator and an electronic apparatus including the resonator are to be provided. A SAW resonator includes: an IDT exciting a SAW using a quartz crystal substrate of Euler angles (?1.5°???1/5°, 117°???142°, 42.79°?|?|?49.57°; one pair of reflection units arranged so as allow the IDT to be disposed therebetween; and grooves acquired by depressing the quartz crystal substrate located between electrode fingers. When a wavelength of the SAW is ?, and a depth of the grooves is G, “0.01??G” is satisfied.

Abstract: It is possible to reduce the size of a surface acoustic wave resonator by enhancing the Q value. In a surface acoustic wave resonator in which an IDT having electrode fingers for exciting surface acoustic waves is formed on a crystal substrate, a line occupying ratio is defined as a value obtained by dividing the width of one electrode finger by the distance between the center lines of the gaps between one electrode finger and the electrode fingers adjacent to both sides thereof, and the IDT includes a region formed by gradually changing the line occupying ratio from the center to both edges so that the frequency gradually becomes lower from the center to both edges than the frequency at the center of the IDT.

Abstract: It is possible to reduce the size of a surface acoustic wave (SAW) resonator by enhancing a Q value. In a SAW resonator in which an IDT having electrode fingers for exciting SAW is disposed on a crystal substrate, the IDT includes a first region disposed at the center of the IDT and a second region and a third region disposed on both sides of the first region. A frequency is fixed in the first region and a portion in which a frequency gradually decreases as it approaches an edge of the IDT is disposed in the second region and the third region. When the frequency of the first region is Fa, the frequency at an edge of the second region is FbM, and the frequency at an edge of the third region is FcN, the variations in frequency are in the ranges of 0.9815<FbM/Fa<0.9953 and 0.9815<FcN/Fa<0.9953, respectively.

Abstract: In a surface acoustic wave resonator in which an IDT having electrode fingers for exciting surface acoustic waves is formed on a crystal substrate, the line occupying ratio causing the maximum electromechanical coupling coefficient and the line occupying ratio causing the maximum reflection of the surface acoustic waves in the IDT are different from each other, the center of the IDT has the line occupying ratio causing an increase in electromechanical coupling coefficient in comparison with the edges of the IDT, and the edges of the IDT have the line occupying ratio causing an increase in reflection of the surface acoustic waves in comparison with the center of the IDT.

Abstract: A SAW resonator which, using a quartz crystal substrate with Euler angles (?1.5°???1.5°, 117°???142°, and 42.79°?|105|?49.57°, includes an IDT which excites a stop band upper end mode SAW, and grooves hollowed out of the substrate positioned between electrode fingers configuring the IDT, wherein, when the wavelength of the SAW is ? and the depth of the inter-electrode finger grooves is G, ? and G satisfy the relationship of 0.01??G and wherein, when the line occupation rate of the IDT is ?, the groove depth G and line occupation rate ? satisfy the relationships of ?2.0000×G/?+0.7200????2.5000×G/?+0.7775 provided that 0.0100??G?0.0500?, ?3.5898×G/?+0.7995????2.5000+G/?+0.7775 provided that 0.0500?<G?0.0695?.

Abstract: A surface acoustic wave resonator includes: an IDT which is disposed on a quartz crystal substrate with an Euler angle of (?1.5°???1.5°, 117°???142°, 41.9°?|?|?49.57°) and which excites a surface acoustic wave in an upper mode of a stop band; and an inter-electrode-finger groove formed by recessing the quartz crystal substrate between electrode fingers of the IDT, wherein the following expression: 0.01??G where ? represents a wavelength of the surface acoustic wave and G represents a depth of the inter-electrode-finger groove, is satisfied and when a line occupancy of the IDT is ?, the depth of the inter-electrode-finger groove G and the line occupancy ? are set to satisfy the following expression: ?2.5×G/?+0.675????2.5×G/?+0.775.

Abstract: A surface acoustic wave resonator includes a piezoelectric substrate and an interdigital transducer (IDT) that includes electrode fingers exciting a surface acoustic wave on the piezoelectric substrate, a first region at a center of the IDT, and a second region and a third region at opposite sides of the IDT. In the IDT, a line occupation rate at which an electromechanical coupling coefficient becomes a maximum is different from the line occupation rate at which reflection of the surface acoustic wave becomes a maximum.

Abstract: The present invention aims to provide a surface acoustic wave (SAW) device including at least two interdigital transducer (IDT) electrodes placed with a predetermined space therebetween on a piezoelectric substrate with improved passband characteristics without increasing the device size. The device includes IDT electrodes 2 and 3 placed with a predetermined space therebetween on a main surface of a piezoelectric substrate 1 and satisfies the formula: 0<(W/D)*fo/109?0.6, where fo is a center frequency measured in Hz, W is the interdigitated length of the IDT electrodes 2 and 3 measured in mm, and D is the distance between the IDT electrodes 2 and 3 measured in mm.