Patent classifications
H03H9/02551
ACOUSTIC WAVE DEVICE
In an acoustic wave device, in a rotated Y-cut crystal substrate to which a rotational angle based on a particular Euler angle is added, a vibration mode located farther in a low phase velocity area than the principal vibration has an electromechanical coupling coefficient K.sup.2 lower than that of the principal vibration, and the primary and secondary temperature coefficients of the principal vibration are approximately zero. The acoustic wave device includes a crystal substrate cut from a quartz crystal boule cut by a rotational angle specified by a right-handed Euler angle (ϕ, θ, Ψ), and at least one comb-shape excitation electrode to excite the crystal substrate to make a plate waves. The crystal substrate is made by cutting the quartz crystal boule such that the rotational angle is within ranges of ϕ=0±2°, θ=17.5° to 19.5°, and Ψ=0±2°.
SURFACE ACOUSTIC WAVE RESONATOR, ITS MANUFACTURING METHOD, AND RADIO CIRCUIT
In a surface acoustic wave resonator according to an embodiment, a quartz-crystal substrate includes an AT-cut 0° X-propagation first quartz-crystal substrate and a Z-cut second quartz-crystal substrate bonded over the first quartz-crystal substrate. A propagation direction of a surface acoustic wave in the second quartz-crystal substrate is inclined from an X-axis of a crystal by 27 to 33°, 87 to 93°, or 147 to 153°, and a thickness of the second quartz-crystal substrate is 0.2 to 1.0 times a wavelength of the surface acoustic wave.
SURFACE ACOUSTIC WAVE FILTER AND MANUFACTURING METHOD THEREFOR
In a surface acoustic wave filter according to an embodiment, a thickness of a piezoelectric crystal substrate bonded over a support substrate made of an oxide crystal is 0.05 to 0.5 μm, and an odd-order harmonic is used.
RESONATOR
A resonator is provided that includes a piezoelectric layer having a first and second surfaces that oppose each other, an IDT electrode on the first surface of the piezoelectric layer, and a high acoustic velocity substrate on the second surface of the piezoelectric layer. The piezoelectric layer is made from a quartz crystal having cut-angles obtained by rotating a plane orthogonal to a crystal Y-axis about a crystal X-axis, in a propagation direction at 90°±10° to the crystal X-axis of the piezoelectric layer, an acoustic velocity in the high acoustic velocity substrate is higher than an acoustic velocity in the piezoelectric layer, and the IDT electrode includes a comb-shaped electrode including multiple electrode fingers aligned in the propagation direction.
COUPLING SURFACE ACOUSTIC WAVE RESONATORS TO A JOSEPHSON RING MODULATOR
A superconducting device that mixes surface acoustic waves and techniques for fabricating the same are provided. A superconducting device can comprise a first surface acoustic wave resonator comprising a first low-loss piezo-electric dielectric substrate. The superconducting device can also comprise a second surface acoustic wave resonator comprising a second low-loss piezo-electric dielectric substrate. Further, the superconducting device can comprise a Josephson ring modulator coupled to the first surface acoustic wave resonator and the second surface acoustic wave resonator. The Josephson ring modulator is a dispersive nonlinear three-wave mixing element.
GUIDED ACOUSTIC WAVE DEVICE
A guided acoustic wave device includes a substrate, a lithium tantalate layer on the substrate, and a transducer on the lithium tantalate film. The lithium tantalate has a crystalline orientation defined by (YXl)Θ°, where Θ is between 10° and 37°. The inventors discovered that limiting the crystalline orientation of the lithium tantalate in this manner provides significant increases in the electromechanical coupling coefficient of the acoustic wave device, thereby increasing bandwidth and improving performance.
SURFACE ACOUSTIC WAVE DEVICE WITH MULTI-LAYER PIEZOELECTRIC SUBSTRATE
A surface acoustic wave device is disclosed. the surface acoustic wave device can include a single crystal support layer, an intermediate single crystal layer positioned over the single crystal support layer, a lithium based piezoelectric layer positioned over the intermediate single crystal layer, and an interdigital transducer electrode positioned over the lithium based piezoelectric layer, the surface acoustic wave device configured to generate a surface acoustic wave. The single crystal layer can be a quartz layer, such as a z-propagation quartz layer. A thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the intermediate single crystal layer, and the thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the lithium based piezoelectric layer.
METHOD OF MANUFACTURING ACOUSTIC WAVE DEVICE WITH MULTI-LAYER PIEZOELECTRIC SUBSTRATE
A surface acoustic wave device is disclosed. The surface acoustic wave device can include a single crystal support layer, an intermediate single crystal layer positioned over the single crystal support layer, a lithium based piezoelectric layer positioned over the intermediate single crystal layer, and an interdigital transducer electrode positioned over the lithium based piezoelectric layer, the surface acoustic wave device configured to generate a surface acoustic wave. The single crystal layer can be a quartz layer, such as a z-propagation quartz layer. A thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the intermediate single crystal layer, and the thermal conductivity of the single crystal support layer is greater than a thermal conductivity of the lithium based piezoelectric layer.
SYSTEMS AND METHODS FOR MEASURING PROPERTIES USING BULK ACOUSTIC WAVES
A measuring system is disclosed. The measuring system includes a surface acoustic wave (SAW) device including a piezoelectric substrate and a first and second electrode disposed on a surface of the piezoelectric substrate, and a measuring device communicatively coupled to the first electrode via a first probe and the second electrode via a second probe and configured to apply an electrical signal to the first and second electrode to generate an incident bulk acoustic wave within the piezoelectric substrate, detect at least a first reflected bulk acoustic wave and a second reflected bulk acoustic wave at the first and second electrode, and calculate a thickness between a first interface corresponding to the first reflected bulk acoustic wave and a second interface corresponding to the second reflected bulk acoustic wave based on a time elapsed between detecting the first and second reflected bulk acoustic waves.
Guided acoustic wave device
A guided acoustic wave device includes a substrate, a lithium tantalate layer on the substrate, and a transducer on the lithium tantalate film. The lithium tantalate has a crystalline orientation defined by (YXl), where is between 10 and 37. The inventors discovered that limiting the crystalline orientation of the lithium tantalate in this manner provides significant increases in the electromechanical coupling coefficient of the acoustic wave device, thereby increasing bandwidth and improving performance.