Murata Manufacturing Co., Ltd.

Murata Manufacturingco., Ltd.

Takuo Hada

Hideya Horiuchi

Kansho Yamamoto

Michio Kadota

Katsumi Fujimoto

Toshimaro Yoneda

Takeshi Nakao

Shinsuke Ikeuchi

Yoichi Mochida

Kenjiro Okaguchi

Osamu Nakagawara

Takao Mouri

Shunsuke Kitamura

A piezoelectric transformer that includes a vibration portion assembly having an output electrode, an output-side intermediate electrode, an input-side intermediate electrode, and an input electrode. The vibration portion assembly includes n vibration portions. The input electrode includes one to n input electrode pieces. The output electrode includes one to n output electrode pieces. Wiring lines are arranged such that voltages of opposite phases can be respectively applied to a first input electrode piece group of the input electrode pieces corresponding to odd-numbered vibration portions, and a second input electrode piece group of the input electrode pieces corresponding to even-numbered vibration portions. The second output electrode piece and the first output-side intermediate electrode piece are superposed with each other in the thickness direction. The first output electrode piece is not superposed with either of the first and second output-side intermediate electrode pieces in the thickness direction.

Piezoelectric transformer

A piezoelectric transformer that includes a base and an upper layer supported by the base. The upper layer includes a first piezoelectric layer that includes the portion of the upper layer that is interposed between an output electrode and an intermediate electrode, and a second piezoelectric layer that is superposed with the first piezoelectric layer and includes the portion of the upper layer interposed between the intermediate electrode and an input electrode in at least n vibration portions. Moreover, the input electrode includes multiple input electrode pieces and the output electrode includes multiple output electrode pieces. In addition, wiring lines are routed such that voltages of opposite phases can be respectively applied to a first input electrode piece group and a second input electrode piece group with the potential of the intermediate electrode serving as a reference.

A piezoelectric device that includes a base member having an opening therein and an upper layer supported by the base member. The upper layer includes a vibration portion at a location corresponding to the opening in the base member. The vibration portion includes a lower electrode, an intermediate electrode and an upper electrode that are spaced apart from one another in a thickness direction of the piezoelectric device. The upper layer includes a first piezoelectric layer disposed so as to be at least partially sandwiched between the lower electrode and the intermediate electrode, and a second piezoelectric layer disposed so as to overlap with the first piezoelectric layer and so as to be at least partially sandwiched between the intermediate electrode and the upper electrode. The first piezoelectric layer and the second piezoelectric layer are different in relative permittivity in the thickness direction of the piezoelectric device.

Piezoelectric device, piezoelectric transformer, and method of manufacturing piezoelectric device

A method for manufacturing a piezoelectric device that includes a substrate and a vibration portion that can include a membrane or a beam that is directly or indirectly supported by the substrate and arranged above the substrate. Moreover, the vibration portion includes a piezoelectric layer and the method includes forming the vibration portion and adjusting a resonance frequency of the vibration portion by locally subjecting a region including the vibration portion to heat treatment.

Method for manufacturing a piezoelectric device

A method for manufacturing a piezoelectric device that includes a substrate, a piezoelectric layer directly or indirectly supported by the substrate and arranged above the substrate, a heater, and a heater electrode for driving the heater. Moreover, the method includes forming the piezoelectric layer, the heater, and the heater electrode and subjecting the piezoelectric device to heat treatment with heat generated from the heater by driving the heater by feeding electric power to the heater electrode.

An electroacoustic transducer includes an ultrasonic element that includes a diaphragm and a support frame, a case body that accommodates the ultrasonic element, and fixing portions that join the support frame portion to a bottom plate portion of the case body. First and second main surfaces of the diaphragm face top and bottom plate portions of the case body, respectively, and a sound hole is provided in the case body. The fixing portions are partially provided along the circumferential direction of the support frame such that a space between the second main surface and the bottom plate portion communicates with a space around the ultrasonic element, and an acoustic path connecting the first main surface and the second main surface and the sound hole is provided in the case body. The fixing portions are defined by a die bonding agent including spherical spacers.

Electroacoustic transducer

A vibrator in a vibrating gyroscope includes a circular annular portion, a rectangular annular portion, and joining portions. The rectangular annular portion is disposed adjacent to an outer side of the circular annular portion. The joining portions join the circular annular portion and the rectangular annular portion. The rectangular annular portion includes linear beam portions. The joining portions join the circular annular portion and the center portions of the beam portions to each other.

Vibrator and vibrating gyroscope

A weight member includes two sides opposite to each other in an X-axis direction when looked at in a plan view. A vibrating beam includes one end portion connected at one location to a fixation member and the other end portion connected at one location to one of the two sides of the weight member in the X-axis direction when looked at in a plan view. The vibrating beam supports the weight member to be displaceable in the X-axis direction. A holding beam includes one end portion connected at one location to the fixation member and the other end portion connected at one location to the other of the two sides of the weight member opposing to each other in the X-axis direction when looked at in a plan view. The holding beam supports the weight member to be displaceable in the X-axis direction. A driver is disposed on the vibrating beam and vibrates the vibrating beam. A detector is disposed on the vibrating beam and configured to output a detection signal changes according to deformation of the vibrating beam.

Acceleration sensor

An acceleration sensor includes a fixation member, a weight member including a plate with two opposing sides parallel or substantially parallel to an X-direction and two opposing sides parallel to a Y-axis direction in a plan view, the weight member including a cutout extending in a direction about 45&#xb0; relative to the X and Y axis directions, a vibrating beam linearly extending in the direction about 45&#xb0; relative to the X and Y axis directions in the plan view, and one end portion is connected to the fixation member and the other end portion is connected to the weight member, the vibrating beam is partly arranged within the cutout and supporting the weight member to be displaceable in a Z-axis direction, a driver disposed on the vibrating beam and vibrating the vibrating beam, and a detector disposed on the vibrating beam and outputting a detection signal that is changed depending on deformation of the vibrating beam.

A vibrator includes first and second circular or substantially circular arc-shaped beam portions, a base end-side weight portion, and a base end-side weight portion joining portion. The end portions of the first and second circular or substantially circular arc-shaped beam portions in an X-axis positive direction face each other across a distance in a Y-axis direction, and the end portions thereof in an X-axis negative direction are joined to each other. The base end-side weight portion is disposed between the first and second circular or substantially circular arc-shaped beam portions. The base end-side weight portion joining portion extends from a joining portion between the first circular or substantially circular arc-shaped beam portion and the second circular or substantially circular arc-shaped beam portion in the X-axis positive direction, and joined to the base end-side weight portion.

A sensor for detecting a substance in liquid includes a sensing circuit including a sensing surface acoustic wave (SAW) element in which a reaction film to react with a substance in liquid, a reference circuit including a reference SAW element including an IDT and not including a reaction film, a first signal source driving the sensing circuit, a second signal source driving the reference circuit and being independent of the first signal source, and a differential circuit arranged to output a differential output between an output of the sensing circuit and an output of the reference circuit. The frequency of a first frequency signal output from the first signal source is different from the frequency of a second frequency signal output from the second signal source, thereby making a driving frequency for the sensing SAW element and a driving frequency for the reference SAW element substantially the same as or different from one another.

Sensor for detecting substance in liquid

A sensor for detecting a substance in liquid includes a sensing oscillation circuit and a reference oscillation circuit. The sensing oscillation circuit includes a sensing SAW element in which a reaction film arranged so as to cover at least one IDT and to react with a substance in liquid is disposed and a first amplifier circuit. The reference oscillation circuit includes a reference SAW element and a second amplifier circuit. The reference SAW element includes at least one IDT and no reaction film. The oscillation frequency of the sensing oscillation circuit and the oscillation frequency of the reference oscillation circuit are separated by at least about 200&#xd7;k(ppm), where k(%) is the electromechanical coupling coefficient of a piezoelectric substrate used in each of the sensing SAW element and the reference SAW element.

A surface acoustic wave device includes a piezoelectric substrate made of LiNbOhaving 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.

Surface acoustic wave device

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.

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Nagaokakyo, Japan

Takuo Hada