摘要:
An acoustic wave device comprising a piezoelectric layer on an omnidirectional acoustic mirror and excitation and/or reception means on a surface of said piezoelectric layer, capable of exciting waves in a band gap of the acoustic mirror.
摘要:
A piezoelectric resonator element includes: a base in a predetermined length, the base being made of a piezoelectric material; a plurality of resonating arms extending from a first end of the base; a joining part connected to a second end apart from the first end of the base by a predetermined distance; a connecting part connected to the joining part and extending in a width direction of the piezoelectric resonator element; a supporting arm connected to the connecting part and extending in a same direction as the resonating arm at an outer side of the plurality of resonating arms. A ratio L3/h is 40% or less where h is a length dimension from the first end of the base to the second end opposite to the resonating arms of the piezoelectric resonator element, and L3 is a width dimension of the connecting part connecting the supporting arm to the base through the joining part.
摘要:
A dual mode piezoelectric filter includes a piezoelectric material layer composed of a piezoelectric thin film of the high-cut type formed on a substrate, a first electrode and a second electrode formed on one of the major surfaces of the piezoelectric material layer with a gap provided therebetween, a third electrode formed on the other major surface of the piezoelectric material layer opposite to the first electrode, the second electrode, and the gap, and an interelectrode mass load element formed in the gap or at a position opposite to the gap on a surface of the piezoelectric material layer. The relationships (p1×h1)≦(pa×ha) and (p2×h2)≦(pa×ha) are satisfied, where h1 is the thickness and p1 is the density of the first electrode, h2 is the thickness and p2 is the density of the second electrode, and ha is the thickness and pa is the density of the interelectrode mass load element. A filter characteristic with a smooth passband and low losses is obtained.
摘要:
A method for manufacturing a quartz oscillator having a stable temperature drift characteristic attributed to the quartz oscillating piece and a quartz oscillator are disclosed.The method comprises a quartz crystal etching step S1 of processing a quartz oscillating piece into a predetermined shape by etching, an electrode membrane forming step S2 of forming an electrode on the quartz oscillating piece, a quartz crystal mounting step S3 of mounting the quartz oscillating piece in an oscillator package, a leakage oscillation adjusting step S4 of driving the mounted quartz oscillating piece, detecting the leakage oscillation, and removing a part of the quartz oscillating piece depending on the detected leakage oscillation, and a re-etching step S6 of re-etching the quartz oscillating piece subjected to the removal.
摘要:
A technique capable of integrally forming SMR type acoustic wave filters corresponding to multiple bands on the same chip at low cost is provided. In SMR type acoustic wave filters including multiple bandpass filters corresponding to multiple bands formed over the same die (substrate), acoustic multilayer films are formed without or with a minimum number of masks and piezoelectric thin films having different thicknesses for respective bands are collectively formed. For example, after the acoustic multilayer films (low acoustic impedance layers and high acoustic impedance layers) are formed in a deep groove in a terrace paddy field shape over the die in a maskless manner, the piezoelectric thin films are c-axis-oriented and grown, and are polished by CMP method or the like to be adjusted in a thickness for respective bands, and therefore, the SMR type acoustic wave filters for multiple bands are formed over the same chip.
摘要:
An electronic component includes a substrate; a piezoelectric material layer supported directly or indirectly by the substrate; a first electrode arranged on a surface of the piezoelectric material layer on an opposite side of the substrate; and a second electrode arranged on a surface of the piezoelectric material layer on the substrate side. The piezoelectric material layer is sandwiched between the first electrode and the second electrode. The first electrode has a smaller surface area than the piezoelectric material layer. A portion where the piezoelectric material layer is exposed from the first electrode includes a portion that is thinner than a thickness of the piezoelectric material layer between the first electrode and the second electrode. Thus, it is possible to configure a resonator with a higher frequency than its ordinary resonance, and it is easy to achieve an adjustment of the resonance frequency of the resonator, as well as improving the yield of the component and enabling the configuration of an electronic component that includes a plurality of resonators of different frequencies.
摘要:
A piezoelectric component comprises at least two stacked crystal filters on a substrate. Each stacked crystal filter comprises a bottom electrode, a first piezoelectric layer arranged above the bottom electrode, a central electrode arranged above the first piezoelectric layer, a second piezoelectric layer arranged above the central electrode, and a top electrode arranged above the second piezoelectric layer. The bottom electrodes are directly connected to one another and the central electrodes are directly connected to one another.
摘要:
The present invention is a method for adjusting the resonant frequency of a mechanical resonator whose frequency is dependent on the overall resonator thickness. Alternating selective etching is used to remove distinct adjustment layers from a top electrode. One of the electrodes is structured with a plurality of stacked adjustment layers, each of which has distinct etching properties from any adjacent adjustment layers. Also as part of the same invention is a resonator structure in which at least one electrode has a plurality of stacked layers of a material having different etching properties from any adjacent adjustment layers, and each layer has a thickness corresponding to a calculated frequency increment in the resonant frequency of the resonator.
摘要:
An object of the present invention is to provide an inexpensive thin film piezoelectric bulk acoustic wave resonator that allows fine-tuning of a resonant frequency. Another object is to provide an inexpensive filter with dramatically improved frequency characteristics, using thin film piezoelectric bulk acoustic wave resonators that can be formed on one substrate. A thin film piezoelectric bulk acoustic wave resonator of the present invention has a laminated structure including a piezoelectric thin film, and a first metal electrode film and a second metal electrode film between which part of the piezoelectric thin film is sandwiched; the first metal electrode film has a plurality of holes formed on an electrode plane opposite to the second metal electrode film and having a depth equivalent to at least the thickness of the first metal electrode film; and if a combined thickness of top and bottom electrode layers and the piezoelectric thin film is ht, the covering ratio σ of the electrode plane of the first metal electrode film satisfies a condition 0
摘要:
A manufacturing method for an electronic component includes a process of forming a lower electrode and a dummy electrode, which are electrically connected to each other, on a substrate, and a process of forming a piezoelectric thin film on the dummy electrode and the lower electrode while a predetermined bias potential is applied to the lower electrode via the dummy electrode. In this method, the piezoelectric thin film is formed on the lower electrode by stabilizing the potential of the lower electrode, thereby decreasing the surface roughness of the piezoelectric thin film. It is thus possible to manufacture an electronic component that exhibits excellent piezoelectric characteristics, in which the electromechanical coupling coefficient and the quality factor of a resonator are increased.