Abstract: A stacked piezoelectric device, which is inexpensive and excellent in electric transmission efficiency and little deterioration of strength of an internal electrode layer, is provided by having an internal electrode layer containing not less than 50 percent by weight of Cu element, and not more than 5 percent of a pore occurrence expressed by (B/A)×100 (%) wherein A is an area of an interface between the internal electrode layer and the piezoelectric layer and B is a sum of areas of pores which appear in the interface and have a diameter of not less than 0.1 micrometers. Preferably, a surface roughness Ra of the interface of the piezoelectric layer contacting the internal electrode layer is not more than 0.5 C (?m) wherein C is a thickness of the internal electrode layer in micrometers. The piezoelectric material constituting the piezoelectric layer preferably comprises PZT which is a Pb(Zr,Ti)O3-based oxide having a perovskite structure.

Abstract: A surface acoustic wave device including an electrode formed from an electrode material represented by the composition formula MxVy wherein M is aluminum or an aluminum-copper alloy, V is vanadium, x+y=100 and 0.10?y<0.2. The device is excellent in durability against applying electric power and diminished in internal resistance.

Abstract: It is an object of the present invention to provide a piezoelectric actuator which uses strontium ruthenate as the material of the bottom electrode, and which uses PMN-PT as the material of the piezoelectric layer. This piezoelectric actuator comprises a base layer (31, 20) of SiO2 or Si ((100) orientation or (110) orientation), a buffer layer (41) constituted by strontium ruthenate (SRO), and a piezoelectric layer (44) constituted by a relaxor dielectric (PMN-PT) with a rhombohedral or quasi-cubic crystal structure oriented in the (001) direction at room temperature.

Abstract: A conjugated polymer actuator having attached electrodes is described wherein direct electrical stimulation induces changes in the dimensions and mechanical properties thereof without the need for electrolytes or counter electrodes.

Abstract: In accordance with the invention, a piezoelectrically actuated relay that switches and latches by means of a solid slug and liquid metal is disclosed. The relay operates by means of a longitudinal displacement of a piezoelectric element in extension mode displacing a liquid metal drop and causing it to wet between at least one contact pad on the piezoelectric element or substrate and at least one other fixed pad to close the switch contact. This motion of the piezoelectric element is rapid and causes the imparted momentum of the solid slug and liquid metal drop to overcome the surface tension forces that would hold the bulk of the liquid metal drop in contact with the contact pad or pads near the actuating piezoelectric element. The switch latches by means of surface tension and the liquid metal wetting to the contact pads.

Abstract: The invention relates to bulk acoustic wave filters including at least two bulk acoustic wave resonators. Each of these resonators includes at least one first electrode, a piezoelectric layer, and a second electrode. At least two of the bulk acoustic wave resonators have effective resonator surfaces which differ in their surface form and/or surface content. The inventive design of the bulk acoustic wave resonators enables optimal suppression of interference modes without influencing the impedance level of the filter.

Abstract: A piezoelectric filter includes a piezoelectric thin film disposed on a silicon substrate, and a plurality of piezoelectric resonators each having electrodes facing each other with the piezoelectric thin film sandwiched therebetween, and each of the plurality of piezoelectric resonators has a filtering function. The electrode material of one of the piezoelectric resonators is different from the electrode material of the other piezoelectric resonators. For example, the former electrode material has a higher stiffness than the latter electrode material. The piezoelectric filter achieves high-Q resonance and improves the attenuation characteristic.

Abstract: The laminated piezoelectric element having a thickness of 100 ?m or less of the present invention comprises a laminate which comprises a plurality of piezoelectric ceramic layers 1, and electrodes 2,3 provided the surface and the inside of the laminate, wherein the electrode 2 comprises a silver-palladium alloy containing 71 to 99.9% by volume of silver and 0.1 to 29% by volume of palladium.

Abstract: A resonator formed by the steps of defining an active single-crystal silicon layer delimited by a buried insulator layer, depositing a silicon-germanium layer by a selective epitaxy method so that the silicon-germanium layer grows above the active single-crystal silicon area, depositing by a non-selective epitaxy method a silicon layer and etching it according to a desired contour, and removing the silicon-germanium by a selective etching with respect to the silicon and to the insulator.

Abstract: A SAW device includes a piezoelectric substrate, and an electrode having a first metal film which is formed over the piezoelectric substrate and is made with a first material, and second metal films which are formed over side walls of the first metal film and are made with a second material which is different from the first material.

Abstract: A surface acoustic wave device includes a piezoelectric plate and at least one interdigital electrode provided on the piezoelectric plate. The interdigital electrode includes a first metallic thin film and a second metallic thin film laminated on the first metallic thin film and containing tantalum as a principal component, and at least a portion of the tantalum of the second metallic thin film is &agr;-tantalum.

Abstract: An electronic element includes a substrate with electrode pads provided thereon. Intermediate electrodes include base electrodes on the bottom surface of the intermediate electrodes, and the bottom surface of the intermediate electrodes are disposed on the electrode pads. Bump electrodes are provided on the intermediate electrodes and include a metal having a melting point of about 450° C. or more. Further, the base electrodes include a metallic material that can reduce orientation of the intermediate electrodes.

Abstract: A form-adaptable electrode structure in layer construction includes at least two conductor layers, between which an insulating layer is disposed, the conductor layers having first and second electrode strips arranged in each case in parallel, and the electrode strips of the first conductor layer being arranged at an angle with respect to the electrode strips of the second conductor layer, so that a net-like structure is formed, and the first electrode strips of the first conductor layer being conductively interconnected with the first electrode strips of the second conductor layer, and the second electrode strips of the first conductor layer being conductively interconnected with the second electrode strips of the second conductor layer via the insulating layer at intersections of the net-like structure.

Abstract: To provide a stacked piezoelectric device which is inexpensive and excellent in bonding strength between a piezoelectric layer and an internal electrode layer, the piezoelectric device comprises piezoelectric layers and internal electrode layers containing not less than 50 percent by weight of Cu stacked alternately. Between the internal electrode layer and the piezoelectric layer, there is a diffusion region formed by mutual diffusion of components of the internal electrode layer and the piezoelectric layer to the other layer and comprising at least one component of the piezoelectric material and Cu. The diffusion region occupies not less than 90 percent of area of interface between the internal electrode layer and the piezoelectric layer, and a thickness of the diffusion region is not more than 10 percent of a thickness of the internal electrode layer.

Abstract: A stator includes first and second piezoelectric elements, a flexible aluminum-based connective arrangement and upper and lower aluminum-based metal blocks. The flexible aluminum-based connective arrangement includes first to fourth aluminum-based electrodes, which apply a voltage to the piezoelectric elements to generate a vibration. Each aluminum-based electrode is made of one of aluminum and an aluminum alloy and directly contacts a corresponding one of axial ends of the piezoelectric elements. Each aluminum-based metal block is made of one of aluminum and an aluminum alloy. The piezoelectric elements and the aluminum-based electrodes are interposed between the aluminum-based metal blocks.

Abstract: A laminated piezoelectric actuator includes piezoelectric plates, and inner electrode layers composed of an electrode material. The piezoelectric plates and the inner electrode layers are laminated alternately. The electrode material includes a metallic component, and an electrically conductive oxide. When the electrically conductive oxide, in which the oxygen ions works as carriers, is added to the electrode material, oxygen is supplied into the operating piezoelectric plates from the inner electrode layers. As a result, the piezoelectric plates are inhibited from degrading.

Abstract: The invention relates to a microbeam oscillator. Tuning of the oscillator is carried out by addition or subtraction of material to an oscillator member in order to change the mass of the oscillator member.

Abstract: In accordance with the invention, a piezoelectrically actuated relay that switches and latches by means of a liquid metal is disclosed. The relay operates by means of a plurality of shear mode piezoelectric elements used to cause a pressure differential in a pair of fluid chambers. Differential pressure is created in the chambers by contracting and expanding the chambers due to action by the piezoelectric elements. The differential pressure causes the liquid metal drop to overcome the surface tension forces that would hold the bulk of the liquid metal drop in contact with the contact pad or pads near the actuating piezoelectric element. The switch latches by means of surface tension and the liquid metal wetting to the contact pads.

Abstract: Disclosed is a piezoelectric resonator that has a piezoelectric plate that has formed thereon a pair of main electrodes and has formed thereon a second electrode surrounding the peripheral edge of the main electrode with a gap being provided between the second electrode and a peripheral edge of the main electrode. The material of the main electrode and the material of the second electrode are differentiated from each other. As the material of the second electrode there is used a material the density of that is lower than the material of the main electrode. With this construction, there is obtained means for suppressing the occurrence of spurious due to an inharmonic mode generating in the high frequency piezoelectric resonator.

Abstract: The laminated piezoelectric element having a thickness of 100 &mgr;m or less of the present invention comprises a laminate which comprises a plurality of piezoelectric ceramic layers 1, and electrodes 2,3 provided the surface and the inside of the laminate, wherein the electrode 2 comprises a silver-palladium alloy containing 71 to 99.9% by volume of silver and 0.1 to 29% by volume of palladium.

Abstract: A method of bonding a piezoelectric element and an electrode, including the steps of forming a first coating of a material selected from the group consisting of Au, Al, Zn, Cu, and Sn on a bonding surface of the piezoelectric element, and forming a second coating of a material selected from the group consisting of Au, Al, Zn, Cu, and Sn on a bonding surface of the electrode. The combination of the materials of the first and second coatings is preferably Au/Au, Au/Al, Zn/Cu, or Sn/Cu. The method further includes the step of bringing the first and second coatings into close contact with each other and heating them under pressure to form a metallic bond or intermetallic compound between the first and second coatings, thereby bonding the piezoelectric element and the electrode.

Abstract: The invention discloses a stacked piezoelectric element comprising a plurality of piezoelectric layers and electrode layers stacked alternately in which the electrode layers are electrically connected by a penetrating electrode formed in a conductive hole formed in a direction of the thickness of the piezoelectric layers, and in which the penetrating electrode formed in a piezoelectric layer of a first layer is so positioned as to overlap with the penetrating electrode formed in a piezoelectric layer of a first layer in the direction of thickness.

Abstract: The present invention provides a piezoelectric thin film element with superior piezoelectric properties in which the condition of the crystal of the piezoelectric thin film is appropriately controlled, and a manufacturing method thereof, as well as a inkjet recording head, inkjet printer, or other liquid ejecting apparatus employing the same. The piezoelectric thin film element 40 comprises a top electrode 44, a bottom electrode 42, and a piezoelectric thin film 43 formed between the top electrode 44 and the bottom electrode 42, wherein the piezoelectric thin film 43 is structured so as to comprise a first layer 431 located nearest to the bottom electrode and second layers (433-436) that are located nearer to the top electrode than the first layer and that each have a thickness greater than that of the first layer 431.

Abstract: An integrally fired, laminated electromechanical transducing element, fabricated using an inexpensive electrode material and having the electrode characteristic at least equivalent to that of the Ag—Pd electrode, is disclosed. Especially, in the integrally fired, laminated electromechanical transducing element according to the invention, (A) the rigidity of the internal electrode layers is low and the internal stress generated at the time of expansion or contraction of the ceramic layers is small, (B) the antimigration characteristic is superior, (C) the charge loss is small, the heat conductivity is high and the heat radiation characteristic is superior, and/or (D) the bonding strength between the ceramic layers and the electrode layers is high.

Abstract: A surface acoustic wave device includes a surface acoustic wave element and an electronic component package for supporting the surface acoustic wave element. The surface acoustic wave element includes a piezoelectric substrate that has interdigital electrodes and electrode pads thereon. The electrode pads input and output electrical signals to and from the respective interdigital electrodes. The electronic component package has electrode pattern sections for inputting and outputting electrical signals. The surface acoustic wave device further includes metal bump connections for electrically connecting between the electrode pads and the respective electrode pattern sections. The electrode pads include aluminum as the major component and copper as a minor component, the copper content being at least about 3.5 percent by weight. To connect the electrode pads to the respective electrode pattern sections, the metal bump connections are formed by a flip chip process using ultrasonic waves.

Abstract: An inexpensive surface acoustic wave apparatus uses a flip chip bonding technique and is capable of reducing an ohmic loss by reducing an electrode electrical resistance and also operates at a high-frequency range. A surface acoustic wave apparatus has a surface acoustic wave element bonded to a package by using a bonding flip chip technique. In the surface acoustic wave element, on a piezoelectric substrate, an IDT electrode, bus bar electrodes, reflector electrodes, relay electrodes, and electrode pads are disposed. Conductive films are disposed on the electrode pads and define a first metallic film, and the conductive films are also disposed on at least any of the bus bar electrodes and the relay electrodes to define a second metallic film.

Abstract: A pump apparatus, which comprises: (a) a tubular portion comprising an electroactive polymer actuator that expands and contracts an inner volume of the tubular portion based upon received control signals; and (b) a control unit electrically coupled to the electroactive polymer actuator and sending control signals to the actuator. The pump apparatus can further include at least one valve that is in fluid communication with the inner volume of the tubular portion. The pump apparatus can be used, for example, as a heart-lung bypass pump apparatus. Also disclosed herein is a method of providing circulatory support for a patent.

Abstract: An apparatus having both a resonator and an inductor fabricated on a single substrate and a method of fabricating the apparatus are disclosed. The apparatus includes a resonator and an inductor that is connected to the resonator. Both the resonator and the inductor are fabricated over their respective cavities to produce a high Q-factor filter circuit.

Abstract: A piezoelectric ceramic body includes a multiplicity of insulating layers, arranged one on top of the other, made of a piezoactive ceramic material, the insulating layers being separated from each other at least in areas by internal electrodes, of which at least one has a silver-containing material at least in areas. The material of the silver-containing internal electrode furthermore has a component reducing or inhibiting the diffusion of silver from the internal electrodes into an insulating layer, in particular a ceramic component on the basis of a PZT ceramic.

Abstract: There is disclosed a piezoelectric/electrostrictive film type device which has a flexural displacement and durability equal to or more than those of a prior art piezoelectric/electrostrictive film type device and which has a remarkably high resonance frequency and which is superior in high-speed response. The piezoelectric/electrostrictive film type device comprises: a substrate formed of ceramic; and a piezoelectric/electrostrictive operation portion including a lower electrode, piezoelectric/electrostrictive layer, and upper electrode which are successively stacked on the substrate and including a projecting end of the piezoelectric/electrostrictive layer with which an upper surface of the lower electrode and a lower surface of the upper electrode are coated, and a projecting portion of the piezoelectric/electrostrictive layer is a connecting material constituted of a hybrid material in which inorganic particles are scattered in a matrix of a polymer compound, and is connected to the substrate.

Abstract: A monolithic piezoelectric transformer includes a drive portion and a power generation portion. The drive portion includes a plurality of polarized piezoelectric ceramic layers and a plurality of internal electrodes that are alternately layered on each other. The drive portion is provided with external input electrodes connected to the internal electrodes. The power generation portion includes a piezoelectric ceramic member and an output electrode. The internal electrodes are formed of a fired metal containing at least one of silver and palladium and at least one of rhodium and iridium.

Abstract: Various piezoelectric transducers are provided. In one form, a polymer film or thin ceramic piezoelectric transducer is formed of various piezoelectric (active) and dielectric (inactive) layers in which the piezoelectric effect may be attenuated locally at any given point on the surface of the transducer, by use of printed circuit patterns, preferably made by photolithography. This provides a practical realization of a distributed piezoelectric transducer with a bi-dimensional polarization profile that varies smoothly over the surface of the piezoelectric structure. Flexibility of the fabrication procedure provides a way to optimize the design of a distributed piezoelectric transducer for applications such as active vibration control. In another form, a segmented piezoelectric transducer includes a set of active elements such as piezofilms, electronics and flexible printed circuits and connected with external electronic circuitry.

Abstract: A system and method for preventing operational and manufacturing imperfections in piezoelectric micro-actuators by physically and electrically isolating conductive layers of the piezoelectric material.

Abstract: A piezoelectric filter includes a piezoelectric thin film disposed on a silicon substrate, and a plurality of piezoelectric resonators each having electrodes facing each other with the piezoelectric thin film sandwiched therebetween, and each of the plurality of piezoelectric resonators has a filtering function. The electrode material of one of the piezoelectric resonators is different from the electrode material of the other piezoelectric resonators. For example, the former electrode material has a higher stiffness than the latter electrode material. The piezoelectric filter achieves high-Q resonance and improves the attenuation characteristic.

Abstract: A process for fabricating a ceramic electroactive transducer of a predetermined shape is disclosed. The process comprises the steps of providing a suitably shaped core having an outer surface, attaching a first conductor to the outer surface of the core, coating an inner conductive electrode on the the outer surface of the core such that the inner conductive electrode is in electrical communication with the first conductor, coating a ceramic layer onto the inner electrode, thereafter sintering the ceramic layer, coating an outer electrode onto the sintered ceramic layer to produce an outer electrode that is not in electrical communication with the first conductor, and then poling the sintered ceramic layer across the inner electrode and the outer electrode to produce the ceramic electrode.

Abstract: A surface acoustic wave device includes a piezoelectric substrate made of a LiNO3 or LiTaO3 single crystal, and an electrode having power endurance. After a damaged layer formed on a surface of the piezoelectric substrate is removed, an under-electrode layer including at least one of Ti and Cr as a main component is formed by a vacuum deposition process at a temperature of about 100° C. or less, and an Al electrode layer including Al or an Al main component is then formed on the under-electrode layer. The Al electrode layer has a twin crystal structure in which the Al crystal is oriented in a desired direction such that the (111) crystal plane of Al substantially coincides with the Z crystal direction of the piezoelectric substrate.

Abstract: A surface acoustic wave device includes a piezoelectric substrate, and at least one interdigital transducer disposed thereon which is made of a metal or an alloy that is heavier than Al. The acoustic velocity distribution of surface acoustic waves in the extending direction of electrode fingers of the at least one interdigital transducer is not greater than about 276 ppm, thereby effectively suppressing considerable ripples, which are noticeably found in the group delay time characteristic in particular, within the bandpass area.

Abstract: A laminated piezoelectric actuator includes piezoelectric plates, and inner electrode layers composed of an electrode material. The piezoelectric plates and the inner electrode layers are laminated alternately. The electrode material includes a metallic component, and an electrically conductive oxide. When the electrically conductive oxide, in which the oxygen ions works as carriers, is added to the electrode material, oxygen is supplied into the operating piezoelectric plates from the inner electrode layers. As a result, the piezoelectric plates are inhibited from degrading.

Abstract: A method for forming a piezoelectric/electrostrictive actuator in which a piezoelectric/electrostrictive file is formed on a vibrating plate or lower electrode by applying a layer of a ceramic paste theron and baking the paste layer at a low temperature in a range below 300° C. to form the film to its final thickness all in one step.

Abstract: A surface acoustic wave device has superior electrical power resistance that is obtained by improving stress migration resistance of electrodes. In order to form at least one electrode, for example, on a &thgr; rotation Y-cut (&thgr;=36° to 42°) LiTaO3 piezoelectric substrate, an underlying electrode layer including Ti or Cr as a primary component is formed, and an Al electrode layer including Al as a primary component is then formed on this underlying electrode layer. The Al electrode layer is an oriented film grown by epitaxial growth and is also a polycrystalline thin film having a twin structure in which a diffraction pattern observed in an X-ray diffraction pole figure has a plurality of symmetry centers.

Abstract: An elastic wave element including a piezoelectric member, at least one electrode which is formed on the piezoelectric member, a corrosion-resistant layer which is formed on a surface of the electrode, a hydrophilic film which is formed on the corrosion-resistant layer and a dielectric film which is formed on the hydrophilic film, in which the corrosion-resistant layer is made is made of a compound of a material of the electrode and the hydrophilic film is made of a material having higher hydrophilic nature than that of the dielectric film such that the corrosion-resistant layer, the hydrophilic film and the dielectric film prevent erosion of the electrode by atmospheric water content.

Abstract: The present invention relates to electroactive polymers that are pre-strained to improve conversion from electrical to mechanical energy. When a voltage is applied to electrodes contacting a pre-strained polymer, the polymer deflects. This deflection may be used to do mechanical work. The pre-strain improves the mechanical response of an electroactive polymer. The present invention also relates to actuators including an electroactive polymer and mechanical coupling to convert deflection of the polymer into mechanical work. The present invention further relates to compliant electrodes that conform to the shape of a polymer. The present invention provides methods for fabricating electromechanical devices including one or more electroactive polymers.

Abstract: A SAW device is highly moisture-resistant, and thus, does not deteriorate in electrical properties. Plural SAW elements each having IDT electrodes mainly composed of aluminum are formed on a piezoelectric substrate. Then, the piezoelectric substrate is soaked in a solution containing phosphorous-ion, washed in water, and dried after being taken out of the solution. The piezoelectric substrate is then divided by dicing into each SAW element after the element is measured in frequency characteristics and sorted. Then, the SAW element is mounted to a package and electrically connected with a wire. Then, a lid closes an opening of the package.

Abstract: A piezoelectric actuator has a plurality of disks made of piezoelectric material, arranged to form a stack in a stack direction, a plurality of flat inside electrodes arranged in alternation with the disks made of piezoelectric material, and at least two outside electrodes applied to the outside of the stack along the stack direction, the inside electrodes each being connected in alternation to one of the outside electrodes by a contact zone. The outside electrodes are applied to the outside of the stack in the form of a coating of an elastic, electrically conductive polymer material.

Abstract: A bending transducer has a piezoelectret carried on a substrate of electrically insulating material. An electrically conductive coating, such as a foil, a grid foil, a grid mesh, or mutually parallel strips, connects the inner electrode of the piezoelectret to the substrate and forms electrical contact with the inner electrode at a number of points. The bending transducer is particularly suited for driving a drafting, weaving or knitting machine in the textile industry.

Abstract: A piezoelectric element includes a plurality of piezoelectric layers which contain a bismuth layer compound as the main component of the piezoelectric ceramic composition. The piezoelectric layers are provided with electrodes containing Pd as a main component so that the piezoelectric layers vibrate. At least one of the electrodes and the piezoelectric ceramic composition contains Ag.

Abstract: The present invention relates to improved devices, systems and methods that convert between electrical and mechanical energy. An electroactive polymer transducer converts between electrical and mechanical energy. An active area is a portion of an electroactive polymer transducer. The active area comprises a portion of an electroactive polymer and at least two electrodes that provide or receive electrical energy to or from the portion. The present invention relates to transducers and devices comprising multiple active areas that are in electrically communication. More specifically, the present invention relates to master/slave arrangements for multiple active areas disposed on one or more electroactive polymers. In a master/slave arrangement, a first active area deflects (a ‘master’), and a second active area reacts (a ‘slave’).

Abstract: A method of bonding a piezoelectric element and an electrode, including the steps of forming a first coating of a material selected from the group consisting of Au, Al, Zn, Cu, and Sn on a bonding surface of the piezoelectric element, and forming a second coating of a material selected from the group consisting of Au, Al, Zn, Cu, and Sn on a bonding surface of the electrode. The combination of the materials of the first and second coatings is preferably Au/Au, Au/Al, Zn/Cu, or Sn/Cu. The method further includes the step of bringing the first and second coatings into close contact with each other and heating them under pressure to form a metallic bond or intermetallic compound between the first and second coatings, thereby bonding the piezoelectric element and the electrode.

Abstract: A surface acoustic wave device includes a substrate and electrode disposed on the substrate. The electrode has a specific resistance &rgr; of up to about 1 &OHgr;·cm and is made of a ZnO film with a low resistance having an impurity doping. A piezoelectric film having a specific resistance &rgr; of at least about 106 &OHgr;·cm and a lattice constant within approximately ±20% of that of ZnO is disposed on the electrode. An interdigital electrode is disposed on the piezoelectric film.

Abstract: The invention relates to an array of ultrasound transducers which each comprise a substrate (1), a membrane (2), a first electrode (4), a piezoelectric layer (5), and a second electrode (6), wherein the substrate (1) comprises at least one opening (3) which adjoins the membrane (2) at one side, while the piezoelectric layer (5) has a high piezoelectric coupling coefficient k and is textured. The invention further relates to an ultrasound transducer and to a method of manufacturing an array of ultrasound transducers.