Abstract: A temperature compensated pair of resonators. The temperature compensated pair of resonators comprises a first resonator configured to resonate at a first frequency and having a first frequency temperature coefficient and a second resonator configured to resonate at a second frequency and having a second frequency temperature coefficient. The second frequency is greater than the first frequency; the second frequency temperature coefficient is less than the first frequency temperature coefficient; and the first and the second resonators are fabricated on a common substrate.

Abstract: A micromachined structure, comprises a substrate and a cavity in the substrate. The micromachined structure comprises a membrane layer disposed over the substrate and spanning the cavity.

Abstract: An electrical resonator comprises a substrate comprising a cavity. The electrical resonator comprises a resonator stack suspended over the cavity. The resonator stack comprises a first electrode; a second electrode; a piezoelectric layer; and a temperature compensating layer comprising borosilicate glass (BSG).

Abstract: A flextensional transducer that can be stored at room temperature and activated and operated at an elevated temperature in excess of 200° C.

Abstract: An ultrasonic transducer (101, 102, 103) includes: a front member (1, 1a) having a front side on which an ultrasonic radiating surface (11) is provided and a back side which is opposite to the front side; a side member (2, 2a); a backing member (3, 3a); and a piezoelectric ceramic body (4), which are provided axially integrally, wherein one end side of the side member (2, 2a) is fitted to the back side of the front member (1, 1a), one end side of the backing member (3, 3a) is fitted to another end side of the side member (2, 2a), and the piezoelectric ceramic body (4) is interposed between the front member (1, 1a) and the backing member (3, 3a).

Abstract: A piezoelectric pressure sensor includes—an outer housing separated by an annular gap from an inner housing, which inner housing is attached to the outer housing on the pressure side. At least one piezoelectric measuring element is positioned between a diaphragm placed on the pressure side of the inner housing and a base part of the inner housing. The inner housing is provided with a massive cylindrical wall throughout whose wall thickness essentially corresponds to the thickness of the adjacent outer housing. In the annular gap between the outer housing and the inner housing a heat-transfer liquid is contained, or in the space between the base part of the inner housing and an interior shoulder of the pressure sensor a heat-transfer spring or bellows is located.

Abstract: Micro-electromechanical devices include a temperature-compensation capacitor and a thin-film bulk acoustic resonator having a first terminal electrically coupled to an electrode of the temperature-compensation capacitor. The temperature-compensation capacitor includes a bimorph beam having a first electrode thereon and a second electrode extending opposite the first electrode. This bimorph beam is configured to yield an increase in spacing between the first and second electrodes in response to an increase in temperature of the micro-electromechanical device. This increase in spacing between the first and second electrodes leads to a decrease in capacitance of the temperature-compensation capacitor. Advantageously, this decrease in capacitance can be used to counteract a negative temperature coefficient of frequency associated with the thin-film bulk acoustic resonator, and thereby render the resonant frequency of the micro-electromechanical device more stable in response to temperature fluctuations.

Abstract: Methods that create an array of BAW resonators by patterning a mass load layer to control the resonant frequency of the resonators and resonators formed thereby, are disclosed. Patterning the surface of a mass load layer and introducing apertures with dimensions smaller than the acoustic wavelength, or dimpling the mass load layer, modifies the acoustic path length of the resonator, thereby changing the resonant frequency of the device. Patterns of variable density allow for further tuning the resonators and for individualized tuning of a resonator in an array of resonators. Patterning a reflowable material for the mass load layer, thereby providing a variable pattern density and distribution followed by elevating the temperature of the mass load layer above its melting point causes the material to liquefy and fill into the apertures to redistribute the mass load layer, thereby, upon subsequent cooling, providing resonators with a predetermined desired resonant frequency.

Abstract: A piezoactuator for injecting fuel with a predetermined fuel pressure has an at least laterally narrowing casing around the internal space of the actuator which has a first temperature- and/or pressure-dependent volume change, a piezo stack located in the internal space which has a second temperature- and/or pressure-dependent volume change, a transmission element which is located between the piezo stack and the casing for transmitting the fuel pressure on the outside of the casing onto the piezo stack, wherein the transmission element has a passivating liquid which has a third temperature- and/or pressure-dependent volume change as well as several preformed bodies which have a fourth temperature- and/or pressure-dependent volume change; wherein the relation between the passivating liquid and the preformed bodies is set that the first volume change of the casing basically corresponds to an overall internal space volume change which has at least the second, third, and fourth volume change.

Abstract: New thermoelectric materials and devices are disclosed for application to high efficiency thermoelectric power generation. New functional materials based on oxides, rare-earth-oxides, rare-earth-nitrides, rare-earth phosphides, copper-rare-earth oxides, silicon-rare-earth-oxides, germanium-rare-earth-oxides and bismuth rare-earth-oxides are disclosed. Addition of nitrogen and phosphorus are disclosed to optimize the oxide material properties for thermoelectric conversion efficiency. New devices based on bulk and multilayer thermoelectric materials are described. New devices based on bulk and multilayer thermoelectric materials using combinations of at least one of thermoelectric and pyroelectric and ferroelectric materials are described. Thermoelectric devices based on vertical pillar and planar architectures are disclosed. The advantage of the planar thermoelectric effect allows utility for large area applications and is scalable for large scale power generation plants.

Abstract: In a composite substrate 10, the piezoelectric substrate 12 which is capable of transmitting an elastic wave and a support substrate 14 which a smaller thermal expansion coefficient than the piezoelectric substrate 12 are bonded to each other. The in-plane maximum thermal strain amount which is the largest thermal strain amount in the plane of the composite substrate 10 has a minimum value and a maximum value when the piezoelectric substrate 12 and the support substrate 14 are relatively rotated 0° to 360°, and the piezoelectric substrate 12 and the support substrate 14 are bonded to each other so that the in-plane maximum thermal strain amount has the minimum value or a value in the vicinity thereof.

Abstract: Thermal expansion matching for an acoustic telemetry system. An acoustic telemetry system includes at least one electromagnetically active element and a biasing device which reduces a compressive force in the element in response to increased temperature. A method of utilizing an acoustic telemetry system in an elevated temperature environment includes the steps of: applying a compressive force to at least one electromagnetically active element of the telemetry system; and reducing the compressive force as the temperature of the environment increases.

Abstract: A boundary acoustic wave device includes a first medium, a second medium, a third medium, and a fourth medium that are laminated in that order and, an electrode including an IDT electrode disposed at an interface between the first medium and the second medium, the temperature coefficient of delay time TCD of a boundary acoustic wave has a positive value, the fourth medium or the second medium has a positive temperature coefficient of sound velocity TCV, the first medium has a negative temperature coefficient of sound velocity TCV, and the sound velocity of transverse wave of the third medium is set to be less than the sound velocity of transverse wave of the fourth medium and/or the second medium.

Abstract: In an actuator unit for an injection system of an internal combustion engine, the difference in the longitudinal extension when a change of temperature of the piezoelectric actuator element occurs affecting the actuator unit is equalized compared to the actuator housing due to different thermal expansion coefficient values in that a fastening element is arranged on the actuator housing. The fastening element is made of a different material than the actuator housing and thus affects a force acting counter to the change of length of the actuator housing.

Abstract: A component has a substrate and a compensation layer. A lower face of the substrate is mechanically firmly connected to the compensation layer. The lower face of the substrate and the upper face of the compensation layer have a topography.

Abstract: The present invention provides a fuel injector, comprising a housing having a sealable injector seat; a fuel injector pin disposed within the housing proximate to the injector seat such that the injector seat may be sealed and unsealed by displacing the fuel injector pin; a resilient element biasing the fuel injector pin in an unsealed direction; a piezoelectric actuator disposed within the housing proximal to the fuel injector pin configured to actuate to force the injector pin towards the injector seat to seal the injector seat; and a thermal compensating unit disposed within the housing proximal to the actuator and configured to compensate for thermal expansion or contraction of a component of the fuel injector.

Abstract: A piezoelectric resonator storage case, includes a piezoelectric resonator stored therein, and a resonator container for storing a metal case. Here, the piezoelectric resonator includes: a piezoelectric resonator body having the metal case and a piezoelectric resonator element which is sealed in the metal case in an air tight manner; and two lead terminals protruding from a bottom of the piezoelectric resonator body.

Abstract: A technique that can make a heat radiation effect higher and makes even a transmission voltage of an ultrasonic diagnostic apparatus higher and then makes a diagnostic depth deeper is disclosed.

Abstract: A piezoelectric ceramic whose resonance frequency temperature characteristic can be easily adjusted is provided. It contains first and second parts (11 and 12) which can be alternately stacked layers. The first and second parts (11 and 12) are each composed of a compound having a bismuth layer structure, such as a complex oxide containing at least Sr, Bi, and Nb, and have degrees of c-axis orientation different from each other. Since the resonance frequency temperature characteristics change according to the degree of orientation, the first and second parts (11 and 12) having different degrees of orientation are appropriately combined so that the resonance frequency temperature characteristics of the piezoelectric ceramic (2) as a whole is easily adjusted.

Abstract: A substrate has a first thermal expansion coefficient and a piezoelectric thin film has a second thermal expansion coefficient. The piezoelectric thin film is mainly composed of a potassium sodium niobate (K,Na)NbO3 with a perovskite structure. A curvature radius of a warping of the substrate provided with the piezoelectric thin film due to difference between the first and the second thermal expansion coefficients is 10 m or more at room temperature. The piezoelectric thin film has a thickness of 0.2 ?m to 10 ?m. The piezoelectric thin film is oriented in one of plane orientations (001), (110), and (111).

Abstract: A fuel injector includes a piezoelectric actuator subassembly having a casing and a piezoelectric element disposed within the casing. The piezoelectric element has an operating temperature range and includes a thermally contractive material having a negative thermal expansion coefficient over a second temperature range overlapping with the operating temperature range. A preload control element is coupled with the piezoelectric element and includes a thermally expansive material having a positive thermal expansion coefficient over the second temperature range. The preload control element maintains a constant preload on the piezoelectric element over a wide temperature range to inhibit temperature induced variability in operation, and can axially lengthen in opposition to axial shortening of the piezoelectric element, responsive to a temperature increase.

Abstract: A substrate has a first thermal expansion coefficient and a piezoelectric thin film has a second thermal expansion coefficient. The piezoelectric thin film is mainly composed of a potassium sodium niobate (K,Na)NbO3 with a perovskite structure. A curvature radius of a warping of the substrate provided with the piezoelectric thin film due to difference between the first and the second thermal expansion coefficients is 10 m or more at room temperature.

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: A drive unit includes a control unit for controlling an ultrasonic actuator. The control unit performs switching between a normal operation mode in which the piezoelectric element unit vibrates at a frequency close to a resonance frequency of longitudinal vibration in the lengthwise direction of the piezoelectric element unit and a resonance frequency of bending vibration to let the ultrasonic actuator output a driving force and a heating mode in which the piezoelectric element unit vibrates at a frequency close to a resonance frequency of longitudinal vibration in the thickness direction of the piezoelectric element unit to heat the piezoelectric element.

Abstract: The piezoelectric actuator comprises: a supporting substrate; a thermal stress controlling layer which is formed on the supporting substrate; and a piezoelectric body which is formed as a film onto the thermal stress controlling layer on the supporting substrate at a higher temperature than room temperature, wherein the thermal stress controlling layer reduces a film stress induced by formation of the piezoelectric body.

Abstract: A quartz crystal resonator includes a quartz crystal resonator element having a main surface including an X axis (electrical axis) and a Z? axis of an inclination rotated at an angle (y) equal to or greater than 36.4 degrees and equal to or smaller than, 40.5 degrees from a Z axis (optical axis) around the X axis, a main vibrating portion vibrating at a predetermined resonance frequency (f) and a supporting portion integrally formed with the main vibrating portion in such a manner as to be formed peripherally to surround the main vibrating portion, and two covers having a thermal expansion coefficient equal to or greater than 6×10?6 per degrees centigrade and equal to or smaller than 10×10?6 per degrees centigrade and bonded to the supporting portion so as to sandwich the quartz crystal resonator element therebetween.

Abstract: A piezoelectric vibrating piece having a first and a second surface at an opposing side of the first surface is comprised of an piezoelectric piece having designated coefficient of thermal expansion; a first electrode film having bigger coefficient of thermal expansion than the designated coefficient of thermal expansion and formed on the first surface; and a second electrode film having smaller coefficient of thermal expansion than the designated coefficient of thermal expansion and formed on the second surface.

Abstract: The invention concerns an actuator which includes a linear piston (2) in an active material, and an inner sliding cylinder (7, 7?) which includes an outer cylinder (5, 5?) in which the said sliding cylinder ((7, 7?) is pre-stressed, with one cylinder being in an anisotropic material with a negative or approximately zero expansion coefficient along at least one axis and a positive or approximately zero expansion coefficient on at least one other axis, and the other cylinder having a positive thermal or approximately zero expansion coefficient.

Abstract: A piezo-electric substrate is mainly comprised of a base material and a film formed on one main surface of the base material. In the base material, the main surface on which the film is formed is a roughed main surface. The piezo-electric substrate is obtained by forming the film comprised of a material with a coefficient of linear expansion smaller than a coefficient of linear expansion of the base material on the roughened main surface using a thermal spraying method.

Abstract: An acoustic wave device includes a piezoelectric substrate, a first dielectric film provided on the piezoelectric substrate, electrodes that are provided on the first dielectric film and excite an acoustic wave, and a second dielectric film that is provided so as to cover the electrodes and is thicker than the electrodes.

Abstract: A micro-electro-mechanical transducer (such as a cMUT) is disclosed. The transducer has a base having a lower portion and an upper portion; a top plate disposed above the upper portion of the base forming a gap therebetween; and a spring-like structure disposed between the top plate and the lower portion of the base. The spring-like structure has a spring layer connected to the lower portion of the base and a spring-plate connector connecting the spring layer and a top plate. In an alternate embodiment, the spring-like has a vertical bendable connector connecting the top plate and the lower portion of the base. The spring-like structure transports the top plate vertically in a piston like manner to perform the function of the transducer. Fabrication methods to make the same are also disclosed.

Abstract: Thermal expansion matching for an acoustic telemetry system. An acoustic telemetry system includes at least one electromagnetically active element and a biasing device which reduces a compressive force in the element in response to increased temperature. A method of utilizing an acoustic telemetry system in an elevated temperature environment includes the steps of: applying a compressive force to at least one electromagnetically active element of the telemetry system; and reducing the compressive force as the temperature of the environment increases.

Abstract: An electronic component having thermal shock resistance and high reliability includes an element having a functional part and a first frame-shaped electrode surrounding the functional part, a substrate including a second frame-shaped electrode, and a solder sealing frame provided on the surface of at least one of the first frame-shaped electrode and the second frame-shaped electrode. In the electronic component device, the element and the substrate are bonded with the solder sealing frame, and the functional part provided on the element is hermetically sealed in a space formed between the element and the substrate.

Abstract: A boundary acoustic wave device includes a stacked structure including a second medium, an IDT electrode, and a first medium, the stacked structure including the first medium having a temperature coefficient of group delay time TCD that is positive. The IDT electrode is stacked on the first medium. The second medium is stacked on the first medium so as to cover the IDT electrode and has a temperature coefficient of group delay time TCD that is negative. A third medium having an acoustic velocity of a transverse wave that is less than an acoustic velocity of a transverse wave of the second medium is arranged at least on a top surface of the IDT electrode.

Abstract: An enclosure for enclosing piezoelectric elements of a piezoelectric actuator comprises a side wall that is shaped to define at least one strain compensation formation selected from a longitudinally-extensible part at which the side wall can be extended or contracted parallel to a longitudinal axis of the enclosure; and an inwardly-deflectable part at which the side wall can be deflected transversely to the longitudinal axis.

Abstract: A substrate has a first thermal expansion coefficient and a piezoelectric thin film has a second thermal expansion coefficient. The piezoelectric thin film is mainly composed of a potassium sodium niobate (K,Na)NbO3 with a perovskite structure. A curvature radius of a warping of the substrate provided with the piezoelectric thin film due to deference between the first and the second thermal expansion coefficients is 10 m or more at room temperature.

Abstract: A MEMS structure having a temperature-compensated resonating member is described. The MEMS structure comprises a stress inverter member coupled with a substrate. A resonating member is housed in the stress inverter member and is suspended above the substrate. The MEMS stress inverter member is used to alter the thermal coefficient of frequency of the resonating member by inducing a stress on the resonating member in response to a change in temperature.

Abstract: A boundary acoustic wave device includes a first medium, a second medium, a third medium, and a fourth medium that are laminated in that order and, an electrode including an IDT electrode disposed at an interface between the first medium and the second medium, the temperature coefficient of delay time TCD of a boundary acoustic wave has a positive value, the fourth medium or the second medium has a positive temperature coefficient of sound velocity TCV, the first medium has a negative temperature coefficient of sound velocity TCV, and the sound velocity of transverse wave of the third medium is set to be less than the sound velocity of transverse wave of the fourth medium and/or the second medium.

Abstract: A piezoelectric resonator includes a piezoelectric layer having a first resonance frequency temperature coefficient of a first sign, a first and a second electrode, the piezoelectric layer being arranged between the first and second electrodes, and a compensation layer arranged between the first electrode and the piezoelectric layer, of a compensation material having a second resonance frequency temperature coefficient of a second sign opposite to the first one, wherein the compensation material is provided with a modification material to increase a conductivity of the compensation layer in a direction of the first electrode and the piezoelectric layer.

Abstract: An acoustic boundary wave device includes a first medium having piezoelectricity, electrodes that are provided on the first medium and excite acoustic waves, a second medium made of a material different from the first medium and provided on the first medium so as to cover the electrodes, and a third medium that has a heat conductivity higher than that of the second medium and is provided so as to contact an upper surface of the second medium and at least a part of side surfaces of the second medium.

Abstract: New thermoelectric materials and devices are disclosed for application to high efficiency thermoelectric power generation. New functional materials based on oxides, rare-earth-oxides, rare-earth-nitrides, rare-earth phosphides, copper-rare-earth oxides, silicon-rare-earth-oxides, germanium-rare-earth-oxides and bismuth rare-earth-oxides are disclosed. Addition of nitrogen and phosphorus are disclosed to optimize the oxide material properties for thermoelectric conversion efficiency. New devices based on bulk and multilayer thermoelectric materials are described. New devices based on bulk and multilayer thermoelectric materials using combinations of at least one of thermoelectric and pyroelectric and ferroelectric materials are described. Thermoelectric devices based on vertical pillar and planar architectures are disclosed. The advantage of the planar thermoelectric effect allows utility for large area applications and is scalable for large scale power generation plants.

Abstract: An apparatus including a piezoelectric substrate having at least one transducer electrode structure. The structure having a metallization formed by one or more metals with a mean specific density that is at least 50% higher than that of aluminum. The structure having a compensation layer that is applied fully or partially over the metallization. The compensation layer is of a material having a temperature dependence of elastic constants that counteracts the temperature coefficient of frequency of the substrate. The compensation layer has a thickness that is less than 15% of an acoustic wavelength of a wave capable of propagation in the structure.

Abstract: A piezoelectric ceramic whose resonance frequency temperature characteristic can be easily adjusted is provided. It contains first and second parts (11 and 12) which can be alternately stacked layers. The first and second parts (11 and 12) are each composed of a compound having a bismuth layer structure, such as a complex oxide containing at least Sr, Bi, and Nb, and have degrees of c-axis orientation different from each other. Since the resonance frequency temperature characteristics change according to the degree of orientation, the first and second parts (11 and 12) having different degrees of orientation are appropriately combined so that the resonance frequency temperature characteristics of the piezoelectric ceramic (2) as a whole is easily adjusted.

Abstract: A piezoelectric actuator with piezoelectric elements, fastened between an actuator head and an actuator foot, and with a plastic sleeve surrounding at least the piezoelectric elements is proposed, which is set in a clamping ring on the actuator head and/or the actuator foot of the piezoelectric actuator. The respective clamping ring may be a metal part or a plastic part, which is equipped with clamping lugs suitable for setting the plastic sleeve and is thrust, pressed, or shrunk onto the respective actuator head and/or actuator foot of the steel piezoelectric actuator.

Abstract: The piezoelectric actuator comprises: a supporting substrate; a thermal stress controlling layer which is formed on the supporting substrate; and a piezoelectric body which is formed as a film onto the thermal stress controlling layer on the supporting substrate at a higher temperature than room temperature, wherein the thermal stress controlling layer reduces a film stress induced by formation of the piezoelectric body.

Abstract: An ultrasonic probe includes piezoelectric elements each including grooves parallel to each other and arrayed in a direction substantially parallel to the grooves, and a mixed member which is to fill the grooves and obtained by mixing in a nonconductive resin member a nonconductive granular substance with a coefficient of thermal expansion of not more than substantially 10?5 K?1.

Abstract: A piezoelectric vibrator has a laminated structure where silicon oxide films having substantially the same thickness are disposed at both faces of piezoelectric plate as dielectric films. Using the structure discussed above, because dielectric films are formed at the both faces of the piezoelectric plate a difference of internal stress, which is caused by a difference of stress relaxation in a long term and affects the piezoelectric plate or the dielectric film, becomes small. Therefore, a warp can be considerably small. As a result, a change, which is caused by the warp of the piezoelectric vibrator, in a resonance frequency of the piezoelectric vibrator can be small.

Abstract: An elastic boundary wave device includes an IDT including laminated conductor layers disposed between a first medium and a second medium, wherein a plane that divides the IDT in half in the thickness direction defines an interface, the energy of an elastic boundary wave present on the side of the first medium of the interface is denoted as E1, and the energy of an elastic boundary wave present on the side of the second medium of the interface is denoted as E2, and wherein if the IDT included only a conductor having the highest density among the laminated conductor layers of the IDT, when the energy of an elastic boundary wave present on the side of the first medium of the interface is denoted as E1? and the energy of an elastic boundary wave present on the side of the second medium of the interface is denoted as E2?, the energies of an elastic boundary wave would satisfy the relationship of E1/E2<E1?/E2? so that the sonic velocity of an elastic boundary wave in the IDT including the laminated conductor lay

Abstract: The temperature-compensated film bulk acoustic resonator (FBAR) device comprises an FBAR stack. The FBAR stack comprises an FBAR and a temperature-compensating element. The FBAR is characterized by a resonant frequency having a temperature coefficient, and comprises opposed planar electrodes and a piezoelectric element between the electrodes. The piezoelectric element has a temperature coefficient on which the temperature coefficient of the resonant frequency depends at least in part. The temperature-compensating element has a temperature coefficient opposite in sign to the temperature coefficient of the piezoelectric element.

Abstract: A restrained surface wave resonator with reduced or abated acceleration sensitivity is provided with a stiffening layer, adhesive layers and subsurface horizontal indentations on the substrate to achieve reduced acceleration sensitivity, increased structural rigidity, decreased sensitivity to in-plane deformations, a lightweight device and reduced deleterious effects from environmental shocks and vibration. The substrate of the restrained surface wave resonators features multiple subsurface horizontal indentations in one major substrate surface deposited on a stiffening layer to provide improved structural rigidity against flexure caused by normal acceleration based upon the diminished mass and reduced weight resulting from removal of portions of the substrate subsurface through micro-machining, and it also tends to improve excessive sensitivity to other flexural deformations. The present invention encompasses a restrained surface wave resonator device and a restrained surface wave resonator system.