Multilayer Patents (Class 310/364)
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Publication number: 20010045793Abstract: There is provided a film bulk acoustic wave device comprising: a silicon substrate 1, a dielectric film 21 including a silicon nitride 16 formed on the substrate 1 and a silicon oxide 2 on the silicon nitride 16, a bottom electrode 3 formed on the dielectric film 21, a piezoelectric film 17 formed on the bottom electrode 3, and a top electrode 5 formed on the piezoelectric film 17, wherein a via hole is formed in such a manner that the thickness direction of a part of the silicon substrate 1 which is opposite to a region including a part where the top electrode 5 exists is removed from the bottom surface of the silicon substrate 1 to a boundary surface with the silicon nitride 16.Type: ApplicationFiled: June 28, 2001Publication date: November 29, 2001Inventors: Koichiro Misu, Kenji Yoshida, Koji Ibata, Shusou Wadaka, Tsutomu Nagatsuka, Fusaoki Uchikawa, Akira Yamada, Chisako Maeda
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Patent number: 6316860Abstract: The surface acoustic wave device of the invention comprises a piezoelectric substrate made up of 64° rotated Y-cut lithium niobate (64LN) or 36° rotated Y-cut lithium tantalate (36LT) and an interdigital electrode formed thereon. The interdigital electrode comprises a titanium buffer metal film and an aluminum film formed thereon. On the 64LN substrate, both the titanium buffer metal film and the aluminum film are converted into a single-crystal film that manifests itself in a spot form alone upon selected-area electron diffraction. By forming the aluminum film on the 36LT substrate with the titanium buffer metal film located therebetween, it is possible to obtain a high-orientation, polycrystalline aluminum film oriented in the (111) direction. The aluminum film is made up of a single-crystal film or a high-orientation polycrystalline film oriented in the (111) direction, whereby migration of aluminum atoms is inhibited, resulting in a power-durability improvement.Type: GrantFiled: May 24, 1999Date of Patent: November 13, 2001Assignee: TDK CorporationInventors: Noritoshi Kimura, Masahiro Nakano, Katsuo Sato
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Patent number: 6307447Abstract: The present invention is a method for adjusting different resonant frequencies of a plurality of mechanical resonators formed on a common substrate, in a case where the resonant frequencies of the resonators are a function of each resonator thickness. According to this method the resonators are each formed with an etchable top electrode layer which includes a material having different etching properties as a topmost layer for each of the resonators having different resonant frequencies. By selectively etching these etchable layers one at a time in the presence of the others, one may adjust the resonant frequencies of each of the resonators without need to mask the resonators during the etching process. Associated with this method there is a resonator structure having a top electrode structure having a topmost layer having different etching characteristics for different resonators.Type: GrantFiled: November 1, 1999Date of Patent: October 23, 2001Assignee: Agere Systems Guardian Corp.Inventors: Bradley Paul Barber, Yiu-Huen Wong, Peter L. Gammel
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Publication number: 20010026114Abstract: In a multilayer piezoelectric actuator device having a laminated structure (3) of a plurality of piezoelectric elements (3a) and a plurality of internal electrodes (3b) alternately stacked, a pair of external electrodes (5) are connected alternately to said internal electrodes. Each of the external electrodes has an electrode layer (11) and a composite layer (13). The electrode layer is formed on a side surface of the laminated structure. The composite layer is formed on the electrode layer and made of a conductive resin including a conductive material. It is preferable that a carbon paper (7) is placed on the composite layer.Type: ApplicationFiled: March 26, 2001Publication date: October 4, 2001Applicant: Tokin Ceramics CorporationInventors: Fumio Takao, Hideaki Kosaka, Narumi Ogura, Kazunobu Matsukawa
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Patent number: 6297580Abstract: As the electrode material of a surface acoustic wave device, a laminated body laminating a second metal layer 5 on a first metal layer 4 is stacked up in two or more stages, and the first metal layer 4 is a metal of which coefficient of diffusion to Al is smaller than the coefficient of self diffusion of Al, and the second metal layer 5 is composed of an Al alloy of three elements or more containing at least one or more metals which forms solid solution with Al at ordinary temperature, and at least one or more metals forming segregation at the grain boundary of Al or an intermetallic compound with Al at ordinary temperature, and therefore the surface acoustic wave device excellent in electric power tolerance, compatible with the conventional pattern forming technology, stable thermally, and capable of preventing increase of insertion loss can be obtained.Type: GrantFiled: March 28, 2000Date of Patent: October 2, 2001Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Ryouichi Takayama, Mitsuhiro Furukawa, Yuji Murashima, Toru Sakuragawa, Koji Nomura
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Patent number: 6291931Abstract: An improved piezoelectric resonator having multiple layers of material within each electrode of the resonator. One layer of material within each electrode is selected and used to increase the effective coupling coefficient between the piezoelectric layer of material in the resonator and the electric fields resulting from the voltages applied to the electrodes. The second layer of material within each electrode is selected and used to decrease the electrical losses within the electrodes.Type: GrantFiled: November 23, 1999Date of Patent: September 18, 2001Assignee: TFR Technologies, Inc.Inventor: Kenneth Meade Lakin
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Patent number: 6259185Abstract: A surface acoustic wave device with electrodes having a metallization of a first layer of substantially pure titanium and a second layer of an alloy of aluminum and titanium. The titanium comprises about 0.1% to about 1.0% by weight of the alloy with aluminum substantially comprising the remainder of the alloy. The titanium of the first layer provides good adhesion and preferential Al(111) grain orientation for the second layer. The titanium of the second layer provides good mechanical strength for improved power handling while the aluminum maintains high electrode conductivity. Small grain structure in the metallization further improves mechanical strength.Type: GrantFiled: December 2, 1998Date of Patent: July 10, 2001Assignee: CTS CorporationInventor: Shouliang Lai
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Patent number: 6252337Abstract: A piezoelectric resonator which can be used as part of a piezoelectric component prevents self-welding of electrodes including silver provided on the surface of a piezoelectric substrate with silver coated terminals with abut with electrodes by forming high fusion point metals on the electrodes 3. The high fusion point metal is made by using Ni, Cr, W, Ti, Mo, Ni—Cu (monel) or their alloy. The thickness of the high fusion point metal is preferably less than about 1/10 of the thickness of the electrode 3 or less than 1 &mgr;m.Type: GrantFiled: July 1, 1996Date of Patent: June 26, 2001Assignee: Murata Manufacturing Co., Ltd.Inventor: Yasuhiro Tanaka
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Patent number: 6239536Abstract: A thin-film piezoelectric resonator and method of fabrication that includes a barrier layer of material between the underlying electrode and a layer of piezoelectric material. For example, in a resonator that uses zinc oxide for the layer of piezoelectric material, a barrier layer of aluminum nitride is deposited upon an underlying aluminum electrode to protect the aluminum electrode from oxidation or structural deformation during the subsequent deposition of the piezoelectric layer of zinc oxide. The barrier layer of aluminum nitride is deposited in a manner so as to provide a substrate having a substantial degree of uniformity of crystal orientation upon which the layer of piezoelectric material may then be deposited in a manner such that the piezoelectric layer will, itself, also have a substantial degree of uniformity in the orientations of its crystals.Type: GrantFiled: September 8, 1998Date of Patent: May 29, 2001Assignee: TFR Technologies, Inc.Inventor: Kenneth Meade Lakin
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Patent number: 6232701Abstract: A piezoelectric component in the form an actuator having a monolithic multi-layer stack is disclosed. The stack comprises a large active cross sectional area and simultaneously exhibits high arc-over resistance between neighboring electrodes of different polarity. For manufacture, only the surface of the stack via which an electrical contacting of the electrode layers ensues is ground after the sintering of a stack composed of piezo ceramic layers and electrode layers arranged on top of one another.Type: GrantFiled: December 22, 1999Date of Patent: May 15, 2001Assignees: Siemens Aktiengesellschaft, EPCOS AGInventors: Carsten Schuh, Karl Lubitz, Dieter Cramer
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Patent number: 6229250Abstract: By using a dual ion-beam sputtering apparatus, an aluminum thin-film is formed on a glass substrate made of an amorphous material. While radiating an ion beam for assisting the film formation from an ion source onto the glass substrate, the aluminum thin-film is formed by depositing the sputtering ions which are generated by radiating an ion beam onto an aluminum target.Type: GrantFiled: January 12, 2000Date of Patent: May 8, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Hidefumi Nakanishi, Atsushi Sakurai, Masato Kobayashi, Yukio Yoshino
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Patent number: 6221271Abstract: A piezoelectric sintered ceramic made of (a) 100 parts by weight of main components having a composition represented by the general formula: (Pb1−yMy)(ZrzTi1−z)O3, wherein M is at least one element selected from the group consisting of Sr, Ba and Ca, and y and z are numbers satisfying 0.01≦y≦0.10, and 0.51≦z≦0.56, respectively; (b) 0.05-1.0 parts by weight, as Fe2O3, of Fe; and (c) 10-1000 ppm of Ag.Type: GrantFiled: March 22, 1999Date of Patent: April 24, 2001Assignee: Hitachi Metals, Ltd.Inventors: Junichi Watanabe, Hiromi Kikuchi, Hideko Fukushima, Shigeru Jomura
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Patent number: 6196059Abstract: Disclosed is a piezoelectric resonator, a process for the fabrication thereof and its use as a sensor element, which implemented in a through-flow cell, is integratable in a measurement system for the determination of the concentration of a substance contained in a liquid and/or for the determination of the physical properties of the liquid. The piezoelectric resonator is designed plane and is provided on its surface with electric contact areas for an electrode and a counter electrode, which is connectable to a signal source as well as to a measurement device. For measuring, the piezoelectric resonator is brought into contact with the to-be-examined liquid on one side, with the resonator responding to the accumulation of the mass of the to-be-detected substance or to a change in the physical properties of the liquid by changing its resonance frequency and/or oscillation amplitude.Type: GrantFiled: August 11, 1998Date of Patent: March 6, 2001Assignee: Fraunhofer Gesellschaft zur Forderung der angewandten Forschung e.V.Inventors: Conrad Kösslinger, Erich Uttenthaler, Andreas Nitsch, Thomas Härle
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Patent number: 6188162Abstract: A megasonic transducer comprised of a stainless steel plate attached to a piezoelectric crystal by an indium attachment layer. To facilitate the attachment, a chromium layer and a silver layer are positioned between the stainless steel plate and the indium layer. Similarly, silver and chromium layers are positioned between the indium layer and the piezoelectric crystal.Type: GrantFiled: August 27, 1999Date of Patent: February 13, 2001Assignee: Product Systems IncorporatedInventor: Richard B. Vennerbeck
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Patent number: 6153967Abstract: An ultrasonic probe has strip-formed oscillators formed of a piezoelectric crystal material arranged in an array form. Metal layers are formed by a first layer of at least one of Ti, Ni and Cr, a second layer of at least one of Cu and Ni, and a third layer of at least one of Cu, Au, Pt, Ag and Pd. A backing material is fixed to the oscillators through the metal layers. With this structure, it is possible to manufacture an ultrasonic probe having a high sensitivity while maintaining a favorable dicing process, even while using a backing material having a low acoustic impedance and soft properties.Type: GrantFiled: September 24, 1998Date of Patent: November 28, 2000Assignee: Kabushiki Kaisha ToshibaInventors: Tsuyoshi Kobayashi, Shiroh Saitoh, Yohachi Yamashita, Senji Shimanuki, Kouichi Harada
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Patent number: 6147438Abstract: The present invention provides a piezoelectric film element with improved adhesion between a first protective film and a substrate. This invention also provides a method of manufacturing a piezoelectric film element, which makes it possible to selectively form, by a hydrothermal synthesis, a piezoelectric film with excellent piezoelectric properties in a specified area. This piezoelectric element comprises, over a substrate 12: a piezoelectric film; a common electrode and an individual electrode located to hold the piezoelectric film in between; a first protective film 14 which is formed over almost the entire surface of the substrate 12 and which protects the substrate 12 to avoid the formation of the piezoelectric film directly over the substrate 12; and a base film 16 which is formed over the first protective film 14 in the area for forming the piezoelectric film, and which functions as a base when the piezoelectric film is caused to grow to be formed.Type: GrantFiled: June 22, 1998Date of Patent: November 14, 2000Assignees: Seiko Epson Corporation, Ube Industries, Ltd.Inventors: Tsutomu Nishiwaki, Masami Murai, Kazuo Hashimoto, Toshihiko Anno
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Patent number: 6141844Abstract: A resonator device having an insulating substrate, a strip-shaped vibrating element which is mounted on said insulating substrate and is provided with driving electrodes formed on the main opposing surfaces of a piezoelectric substrate, and terminal electrodes which are provided on said insulating substrate so as to be electrically connected with said driving electrodes and to which driving signals are applied by an external signal source. At least the longitudinal side portions of said vibrating element are coated with a surface active agent. With such a constitution, fluctuations in resonant resistance which are due to the excitation level can be suppressed, thereby contributing to the stable operation of the device, reducing the number of producing steps, and raising the yield rate in production.Type: GrantFiled: February 13, 1998Date of Patent: November 7, 2000Assignee: Fujitsu LimitedInventors: Takashi Miyagawa, Masanori Yachi
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Patent number: 6080328Abstract: The present invention provides a method for producing a piezoelectric ceramic element in which evaporation of Pb contained in a piezoelectric material is prevented and which allows use of inexpensive metal as an electrode material without substantial deterioration of piezoelectric characteristics. The method includes the steps of (1) mixing at least oxides of Pb, Zr, Ti, Cr and Nb; (2) calcining the mixture; (3) crushing the calcined product and adding a Cu component in an amount of about 0.05-3.0 wt. % calculated as CuO; (4) adding a binder to the Cu-component-containing mixture; (5) molding the binder-containing mixture; (6) firing the molded product at 1100.degree. C. or less to produce a sintered product; and (7) forming electrodes on surfaces of the sintered product, the sintered product containing a primary component represented by the formula:Pb.sub.a [(Cr.sub.x Nb.sub.(1-x)).sub.y Zr.sub.(1-b-y) Ti.sub.b ]O.sub.3wherein 0.95.ltoreq.a.ltoreq.1.05; 0.40.ltoreq.b.ltoreq.0.55; 0.10.ltoreq.x.ltoreq.0.Type: GrantFiled: April 13, 1999Date of Patent: June 27, 2000Assignee: Murata ManufacturingInventor: Katsuhiro Horikawa
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Patent number: 6046530Abstract: A piezoelectric resonance component is constructed to allow for easy automatic assembly and eliminates a short-circuit between a ring terminal and a dot terminal while achieving excellent performance characteristics at a low material cost. In the piezoelectric resonance component, the piezoelectric resonator is contained in an outer case with a ring-shaped peripheral electrode and a dot-shaped center electrode in contact with one side of a sheet-shaped anisotropic conductor. A plurality of protrusions provided on arm portions of the ring terminal and a protrusion on the dot terminal are in pressure-contact with the other side of the anisotropic conductor. A dimension L1 of the anisotropic conductor in the direction in which the arm portions of the ring terminal are led out is shorter than a distance D1 from the edge of a lead portion of the ring terminal to the end of the arm portions, and the anisotropic conductor is biased toward an inner wall of the outer case.Type: GrantFiled: July 16, 1998Date of Patent: April 4, 2000Assignee: Murata Manufacturing Co., Ltd.Inventor: Hirofumi Funaki
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Patent number: 6025669Abstract: A piezoelectric resonator which can be used as part of a piezoelectric component prevents self-welding of electrodes provided on the surface of a piezoelectric and which include silver with silver coated terminals with which the electrodes abut by forming high fusion point metals on the electrodes. The high fusion point metals include Ni, Cr, W, Ti, Mo, Ni--Cu (monel) or their alloy. The thickness of the high fusion point metal is preferably less than about 1/10 of the thickness of the electrode or less than 1 .mu.m.Type: GrantFiled: March 3, 1998Date of Patent: February 15, 2000Assignee: Murata Manufacturing Co., Ltd.Inventor: Yasuhiro Tanaka
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Patent number: 5958285Abstract: Disclosed is a sintered piezoelectric ceramic which is resistant to the high voltage for polarization with no dielectric breakdown and has good moisture resistance. When a plurality of the ceramics are fired, they are prevented from being fused and combined together. The production costs of the ceramic are low. The sintered piezoelectric ceramic comprises particulate or agglomerate zirconia grains dispersed in piezoelectric ceramic grains, in which the mean grain size of the piezoelectric ceramic grains is smaller than that of the zirconia grains.Type: GrantFiled: June 26, 1998Date of Patent: September 28, 1999Assignee: Murata Mnufacturing Co., Ltd.Inventors: Koichi Kawano, Kazuya Kamada
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Patent number: 5909156Abstract: A surface acoustic wave device includes an electrode formed by a first film and a second film on a substrate, the first film including an Al film or a film formed by adding at least one other element to Al, and the second film including a metal whose coefficient of diffusion into Al is greater than a self diffusion coefficient of Al. The present invention contributes to improvement of the high-power durability of the electrodes.Type: GrantFiled: December 11, 1996Date of Patent: June 1, 1999Assignee: Fujitsu LimitedInventors: Tokihiro Nishihara, Hidema Uchishiba, Osamu Ikata, Yoshio Satoh
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Patent number: 5844349Abstract: An improved composite ultrasonic transducer, and elements therefor, which may be made autoclavable, and a method of making these elements. A number of planar precursors comprising strips of piezoelectric ceramic material separated from one another by a polymer material are stacked one above another with the ceramic strips aligned with one another, and with electrical conductors disposed between each of the planar precursors. These precursors are then bonded to one another, to form a bonded assembly. The bonded assembly is then slit along parallel lines perpendicular to the direction of elongation of the ceramic strips, subdividing the strips into individual ceramic members and also subdividing the planar conductors, forming ribbon-like conductors extending between opposite sides of the array. The saw kerfs are filled with a hardening polymer material. The ribbon-like conductors reaching the edges of the assembly are then connected electrically in parallel, reducing the capacitance of the individual emitters.Type: GrantFiled: February 11, 1997Date of Patent: December 1, 1998Assignee: Tetrad CorporationInventors: Clyde G. Oakley, Stephen J. Douglas
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Patent number: 5844347Abstract: A SAW device comprising an inter-digital electrode capable of withstanding application of excessive electric power, while preventing an increase of insertion loss. The SAW device has an inter-digital electrode formed by alternating layers of aluminum films and conductive films, where the conductive films have an elastic constant greater than that of the aluminum films.Type: GrantFiled: August 29, 1996Date of Patent: December 1, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Ryoichi Takayama, Keizaburo Kuramasu, Toshio Sugawa
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Patent number: 5828159Abstract: A resonator device having an insulating substrate, a strip-shaped vibrating element which is mounted on said insulating substrate and is provided with driving electrodes formed on the main opposing surfaces of a piezoelectric substrate, and terminal electrodes which are provided on said insulating substrate so as to be electrically connected with said driving electrodes and to which driving signals are applied by an external signal source. At least the longitudinal side portions of said vibrating element are coated with a surface active agent. With such a constitution, fluctuations in resonant resistance which are due to the excitation level can be suppressed, thereby contributing to the stable operation of the device, reducing the number of producing steps, and raising the yield rate in production.Type: GrantFiled: June 4, 1997Date of Patent: October 27, 1998Assignee: Fujitsu LimitedInventors: Takashi Miyagawa, Masanori Yachi
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Patent number: 5818151Abstract: An electrode for an electronic component includes a nickel-chrome alloy layer located on an surface of the electronic component, and a copper layer located on the nickel-chrome alloy layer. The electrode can be adapted to be used as a vibrating electrode of a piezoelectric device.Type: GrantFiled: February 13, 1996Date of Patent: October 6, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Hitto Takai, Shushi Saoshita
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Patent number: 5809626Abstract: To a ceramic green sheet for a substrate, in which holes for throughholes were formed, a ceramic connecting paste is printed so that a plurality of non-printed portions corresponding to a disposition pattern of a plurality of inner spaces are formed, and a connecting layer for dividing a space into sections is formed so that the connecting paste is not present in portions where the plurality of inner spaces are formed. Then, a thin ceramic green sheet for a diaphragm plate the thin diaphragm plate, is superposed on the connecting layer to obtain a laminate, and the laminate is fired to obtain a unitary multidiaphragm structure. The method provides a multidiaphragm structure free from exfoliation of a laminated layer caused between laminated green sheets and free from deformation of a diaphragm portion caused by punching or handling.Type: GrantFiled: February 19, 1997Date of Patent: September 22, 1998Assignee: NGK Insulators, Ltd.Inventors: Yukihisa Takeuchi, Tsutomu Nanataki, Nobuo Takahashi
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Patent number: 5773917Abstract: This invention relates to a surface acoustic wave device and a production process thereof. An electrode is formed by alternately laminating a film of an aluminum alloy containing at least copper added thereto and a copper film on a piezoelectric substrate. While the particle size of the multi-layered electrode materials is kept small, the occurrence of voids in the film is prevented and life time of the surface acoustic wave device is elongated.Type: GrantFiled: May 23, 1997Date of Patent: June 30, 1998Assignee: Fujitsu LimitedInventors: Yoshio Satoh, Osamu Ikata, Hidema Uchishiba, Takashi Matsuda, Tokihiro Nishihara, Mitsuo Takanatsu, Hajime Taniguchi
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Patent number: 5669126Abstract: A terminal for a piezoelectric device has a first electrode portion, a second electrode portion folded on the first electrode portion, projections on the first and second electrode portions, and further a vibration absorber between the first and second electrode portions. As the vibration absorber, oil, a non-volatile component of oil, silicone grease, polyamide resin, paper, an anticorrosive, a coating agent, silicone rubber, etc. may be used. Another terminal for a piezoelectric device has a sealant between the first electrode portion and the second electrode portion.Type: GrantFiled: September 5, 1995Date of Patent: September 23, 1997Assignee: Murata Manufacturing Co., Ltd.Inventors: Koichi Nagano, Atsushi Uno, Toshiyuki Baba, Takashi Shimura, Yuusei Oyama
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Patent number: 5625149Abstract: A multilayer composite transducer is disclosed. The multilayer composite transducer comprises a plurality of layers wherein a piezoelectric material is dispersed periodically within a polymer matrix. The piezoelectric material is typically formed into columns or slabs, and these columns and slabs need to be aligned from one layer to the next. As this alignment can be difficult to perform, the present invention teaches a first method for fabricating the multilayer composite transducer which allows the alignment to be easily accomplished and a second and third method which reduce or eliminate the need for the alignment.Type: GrantFiled: July 27, 1994Date of Patent: April 29, 1997Assignee: Hewlett-Packard CompanyInventors: Turukevere R. Gururaja, Larry A. Ladd
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Patent number: 5523645Abstract: An electrostrictive effect element has a laminated-structure formed by a plurality of electrostrictive ceramic members and a plurality of internal electrode conductive layers which are stacked alternatingly. The electrostrictive effect element has, on each of the opposite side surfaces of the laminated-structure, an external electrode conductive layer which is formed by a plurality of land conductors made of sintered-type conductive paste for interconnecting the exposed internal electrode conductive layers not covered by glass insulation layers, and a belt-like conductor made of resin hardening-type conductive paste for interconnecting the plurality of land conductors. Silver diffusion into the glass insulation layers can be avoided while maintaining low contact resistance between the external electrode conductive layer and the internal electrode conductive layers.Type: GrantFiled: December 7, 1994Date of Patent: June 4, 1996Assignee: NEC CorporationInventor: Takayuki Inoi
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Patent number: 5512796Abstract: A co-fired laminate (10) for use in printheads for drop-on-demand ink jet printers has two inner layers (12, 14) of piezoelectric material which are thickness poled in opposite senses, two outer layers (11, 15) of inactive material and a fifth layer (13) disposed between the inner layers which is electrically insulating under the printhead operating conditions and conductive under the poling conditions of the inner layers. The fifth layer preferably is an N.T.C. material with its critical temperature between the operating and poling temperatures. After poling of the inner layers further manufacture of the printhead from one side thereof can be effected as described.Type: GrantFiled: May 27, 1993Date of Patent: April 30, 1996Assignee: Xaar LimitedInventor: Anthony D. Paton
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Patent number: 5504388Abstract: A piezoelectric/electrostrictive element is disclosed which includes at least one piezoelectric/electrostrictive portion each of which consists of a lower electrode film, a piezoelectric/electrostrictive film and an upper electrode film. In this element, at least the lower one of the electrode films has a surface roughness represented by maximum peak-to-valley roughness height Rmax. or Ry which is in a range of 3 .mu.m.about.14 .mu.m, and a surface roughness represented by centerline mean roughness Ra which is not larger than 2 .mu.m.Type: GrantFiled: March 8, 1994Date of Patent: April 2, 1996Assignee: NGK Insulators, Ltd.Inventors: Koji Kimura, Satoshi Takemoto, Yukihisa Takeuchi
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Patent number: 5459371Abstract: Disclosed is a multilayer piezoelectric element in which the anisotropic conductive layers are formed on two side surfaces, each surface opposing with each other, of the multilayer piezoelectric element that a plurality of the piezoelectric plates and the internal electrodes are alternately stacked and the conductive portions are alternately formed in the anisotropic conductive layer corresponding to the internal electrodes disposed on each side surface, thereby the internal electrodes and the external electrodes are electrically connected with each other on each side surface through the conductive portions.Type: GrantFiled: March 14, 1994Date of Patent: October 17, 1995Assignee: Brother Kogyo Kabushiki KaishaInventors: Yasuo Okawa, Yasuo Imoto
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Patent number: 5406682Abstract: A method of compliantly mounting piezoelectric device with a substrate. First, outer portions of a piezoelectric element are selectively metallized. Next, one layer of aluminum is selectively dispensed on the piezoelectric element. Third, an uncured conductive compliant material is placed and aligned on a substrate. Fourth, the piezoelectric element is placed and aligned on the conductive compliant material, such that upon curing the conductive compliant material forms a compliant mount connecting the outer metallized portions of the piezoelectric element with the substrate.Type: GrantFiled: December 23, 1993Date of Patent: April 18, 1995Assignee: Motorola, Inc.Inventors: Charles Zimnicki, Iyad Alhayek
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Patent number: 5406164Abstract: Disclosed is a multilayer piezoelectric element in which the conductive layers, each having a first layer including conductive particles and a second insulating layer, are formed on two side surfaces, each surface opposing with each other, of the multilayer piezoelectric element that a plurality of the piezoelectric plates and the internal electrodes are alternately stacked and the conductive portions are alternately formed in the conductive layer based on the conductive particles corresponding to the internal electrodes disposed on each side surface, thereby the internal electrodes and the external electrodes are electrically connected with each other on each side surface through the conductive portions.Type: GrantFiled: April 26, 1994Date of Patent: April 11, 1995Assignee: Brother Kogyo Kabushiki KaishaInventors: Yasuo Okawa, Yasuji Chikaoka, Yasuo Imoto
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Patent number: 5404067Abstract: A piezoelectric bending transducer includes two piezoceramic layers each having two sides and electrodes on both of the sides. A graphite fiber layer is glued between the piezoceramic layers with an epoxy resin. The graphite fiber layer has a greater length than the two piezoceramic layers defining an exposed part of the graphite fiber layer. A copper foil is glued to the exposed part. The copper foil has an area for disposition of a solder contact. A process for producing a bending transducer includes placing a graphite fiber layer impregnated with incompletely hardened epoxy resin between two polarized piezoceramic layers. The graphite fiber layer is glued between the piezoceramic layers upon hardening of the epoxy resin. A copper foil is glued onto the graphite fiber layer, preferably simultaneously with the gluing of the two piezoceramic layers.Type: GrantFiled: May 26, 1994Date of Patent: April 4, 1995Assignee: Siemens AktiengesellschaftInventors: Christian Stein, Thomas Mockl
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Patent number: 5334303Abstract: A quartz crystal resonator is utilized to effect evaluation of the viscoelastic characteristic of a film deposited on an electrode by an electrochemical reaction. The quartz crystal resonator is connected to a resonator characteristic measurement unit comprised of an oscillating circuit, a frequency counter, and an amplitude level meter. An electrochemical measurement unit in the form of a potentiostat is connected to a working electrode which comprises one of the electrodes of the resonator, to a reference electrode and to a counter electrode. The frequency counter, the amplitude level meter and the potentiostat are connected to a CPU. The resonator, reference electrode and counter electrode are all immersed in an electrolyte solution in an electrochemical cell.Type: GrantFiled: March 16, 1992Date of Patent: August 2, 1994Assignee: Seiko Instruments Inc.Inventors: Hiroshi Muramatsu, Xuanjing Ye
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Patent number: 5329202Abstract: The description details a preferred embodiment of an improved large area ultrasonic transducer 70 capable of reducing the generation of adverse "edge effect" waves. The transducer has a thin piezoelectric wafer 72 that has a high area-to-thickness ratio of preferably between 30 and 300. A front electrode coating 84 is deposited on the front surface 74, over the front edge 77, along the side surface 82 and over the back edge 78 and onto a border of the back surface 76 to minimize the application of a voltage potential along the side surface.A voltage modifying layer 92 is placed on the back surface 76 along the back edge 78 for further minimizing the generation of "edge effect" waves. The layer 92 varies in thickness to progressively decrease the voltage applied to the back surface 76 from a large central area 79(a) to the back edge 78. The layer 92 is preferably composed of a non-piezoelectric dielectric material.Type: GrantFiled: November 22, 1991Date of Patent: July 12, 1994Assignee: Advanced Imaging SystemsInventors: George F. Garlick, Todd F. Garlick
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Patent number: 5325012Abstract: The features of the present invention are 1) to apply metallization on the bonding surface of a piezoelectric ceramic with a metal likely to react with the piezoelectric ceramic material, 2) when the piezoelectric ceramic material is soldered on the bonding surface, to apply metallization with a metal likely to react with the solder material, 3) to provide between the metallizing layers formed in 1) and 2) a metallizing layer including metal which prevents reaction between the metals and their diffusion, 4) to use a mounting member for the piezoelectric ceramic which has substantially the same thermal expansion coefficient as the piezoelectric ceramic in non-polarization condition and 5) to solder in the non-polarization condition and thereafter to polarize.Type: GrantFiled: February 20, 1992Date of Patent: June 28, 1994Assignees: Hitachi, Ltd, Hitachi Material Engineering, Ltd., Hitachi Engineering Service Co., Ltd.Inventors: Ichiya Sato, Takao Yoneyama, Hisanori Okamura, Satoshi Kokura, Minoru Yanagibashi
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Patent number: 5268610Abstract: An acoustic ink printer transducer comprising a piezoelectric layer positioned between two suitable electrode materials. Also, a method for obtaining second harmonic operations from an acoustic ink printer transducer to enable ejection of a number of different ink droplet sizes from the acoustic ink printer thereby facilitating grey scale printing.Type: GrantFiled: December 30, 1991Date of Patent: December 7, 1993Assignee: Xerox CorporationInventors: Babur B. Hadimioglu, Butrus T. Khuri-Yakub, Eric G. Rawson
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Patent number: 5245734Abstract: Multilayer piezoactuators are made by stacking and pressing alternating layers of piezoceramic material and interdigital electrode material. The electrode structure is provided with pressure protected boundary discontinuities which form areas in which electrodes edges do not make contact with the common electrical collectors of the piezoactuators and in which the piezoceramic layers are prevented from touching one another.Type: GrantFiled: October 26, 1990Date of Patent: September 21, 1993Assignee: Battelle Memorial InstituteInventor: Jean-Paul Issartel
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Patent number: 5247220Abstract: An ultrasonic step motor is provided with a stator and rotor. The rotor has a plurality of projections extending in the direction of the stator so that contact is made between the rotor and the stator creating a frictional force to drive the rotor. Vibrators are formed from a piezoelectric material directly attached to the stator. The ultrasonic motor further includes a drive control apparatus for impressing standing waves to the vibrating elements of the vibrator causing a change over to the phase or carrying out an ON-OFF operation of the ultrasonic motor.Type: GrantFiled: October 22, 1990Date of Patent: September 21, 1993Assignee: Seiko Epson CorporationInventors: Osamu Miyazawa, Kiyoto Takedo
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Patent number: 5233260Abstract: In an overall stacked piezoelectric element, the material for the electrode was selected from aluminum, nickel and copper each alone or alloys based on aluminum, nickel or copper, and further the parts of the electrodes which contact with molding resin on the side face of the stacked body and the parts which have to be insulated from the lead-out terminals were subjected to an oxidation or nitriding treatment. As the result, an improved element was obtained which is of a high reliability, suited to low voltage operation and suffers no short-circuit of the electrodes even when water permeates to the side face of the stacked body during operation in a humid atmosphere.Type: GrantFiled: July 15, 1992Date of Patent: August 3, 1993Assignees: Hitachi, Ltd., Hitachi Metals, Ltd.Inventors: Takeshi Harada, Akiomi Kohno, Akiomi Kohno, Shigeru Jomura
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Patent number: 5233261Abstract: An AT-cut quartz crystal for a quartz crystal microbalance has a buffer layer sandwiched between an adhesion layer and an electrode layer on the front or deposition side of the crystal. The buffer layer can be a zinc layer of 6000 .ANG. sandwiched between a titanium or chromium adhesion layer of 100 to 160 .ANG. and a gold, silver, or aluminum outer electrode layer of about 2000 .ANG.. The zinc layer has a relatively low bulk modulus, and absorbs stress imposed by the deposited layer. The buffer layer prolongs useful crystal life, particularly when depositing dielectric materials. The crystal should have a modest surface roughness as keying-in structure.Type: GrantFiled: December 23, 1991Date of Patent: August 3, 1993Assignee: Leybold Inficon Inc.Inventor: Abdul Wajid
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Patent number: 5202600Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.Type: GrantFiled: September 10, 1990Date of Patent: April 13, 1993Assignee: Seikosha Co., Ltd.Inventors: Masanori Fujita, Shinichi Okamoto, Hirokazu Ono
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Patent number: 5196756Abstract: According to the present invention, there are provided a stack-type piezoelectric element constructed of a stacked body comprising plural layers of sintered piezoelectric ceramic material and electrodes which lie between the respective layers of the piezoelectric ceramic material, wherein said electrodes are formed of a material capable of diffusion-bonding with said piezoelectric ceramic material at a lower temperature than the sintering temperature of said ceramic material, a process for producing the same, and a stack-type piezoelectric device using said stack-type piezoelectric element.Type: GrantFiled: August 29, 1990Date of Patent: March 23, 1993Assignee: Hitachi Ltd.Inventors: Akiomi Kohno, Masatugu Arai, Takeshi Harada
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Patent number: 5196757Abstract: A piezoelectric ceramic actuator having a laminated body obtained by alternately laminating a plurality of piezoelectric ceramic layers and a plurality of internal electrode layers in which at least one part of two adjacent ceramic layers, having the internal electrode sandwiched therebetween, are bonded to each other through particles of ceramic powder contained within the internal electrode. As a result of this structure, the bonding strength between the ceramic layer and the internal electrode can be greatly increased compared with conventional designs, thus improving the impact resistance of the actuator. The average particle size of the ceramic powder contained within the internal electrode ranges from one-third to one times (preferably from one-half to one times) the thickness of the internal electrode, and the mixing ratio of the ceramic powder ranges from 10 to 20 weight percent to electroconductive materials within the internal electrode.Type: GrantFiled: March 30, 1992Date of Patent: March 23, 1993Assignee: NEC CorporationInventor: Kenichi Omatsu
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Patent number: 5187402Abstract: A piezoelectric device includes a first electrode, a second electrode disposed in opposing, spaced relation to the first electrode, a ferroelectric liquid crystal interposed between the first and second electrodes, a first alignment layer formed between the first electrode and the ferroelectric liquid crystal, and a second alignment layer formed between the second electrode and the ferroelectric liquid crystal.Type: GrantFiled: September 10, 1990Date of Patent: February 16, 1993Assignee: Seikosha Co., Ltd.Inventors: Masanori Fujita, Shinichi Okamoto, Hirokazu Ono
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Patent number: 5162690Abstract: Interdigital transducers (3, 4) and reflectors (5, 6) are formed on a piezoelectric substrate (2) by an aluminum film. The aluminum film is crystallographically oriented in a constant direction, whereby stressmigration of the aluminum film is suppressed.Type: GrantFiled: April 12, 1990Date of Patent: November 10, 1992Assignee: Murata Manufacturing Co., Ltd.Inventors: Hideharu Ieki, Atsushi Sakurai, Koji Kimura