Piezoelectric Properties Patents (Class 427/100)
  • Patent number: 5700359
    Abstract: A method of polarizing at least one large area sheet of ferroelectric material (1). The method comprises the following successive steps: placing films of ferroelectric material (2, 3) of thickness e.sub.1 against two opposite faces (1a, 1b) of the sheet (1) of thickness e.sub.2, the thickness e.sub.1 being a function of the respective coercive fields of the materials constituting the sheet (1) and the films (2, 3); placing electrodes (4, 5) on either side of and against the films of ferroelectric material (2, 3); compressing the resulting complex; and applying a cyclical voltage between the two electrodes (4, 5).
    Type: Grant
    Filed: February 20, 1996
    Date of Patent: December 23, 1997
    Assignee: Institut Franco Allemand de Recherches de Saint-Louis
    Inventor: Fran.cedilla.ois Bauer
  • Patent number: 5692279
    Abstract: A monolithic thin film resonator, lattice filter including spaced apart strips of a conductive film positioned on a substrate so as to define a first set of I/O terminals, a layer of piezoelectric material positioned on the conductive film, and spaced apart conductive strips of a conductive film positioned on the piezoelectric layer orthogonal to the first strips to form cross-over areas, each defining a thin film resonator and a second set of I/O terminals. A plurality of portions of a dielectric film are positioned on selected cross-over areas to mass load the thin film resonators so as to lower the resonant frequency.
    Type: Grant
    Filed: August 17, 1995
    Date of Patent: December 2, 1997
    Assignee: Motorola
    Inventors: Luke Mang, Fred S. Hickernell, Robert G. Kinsman
  • Patent number: 5683614
    Abstract: A method of forming a layered-perovskite bismuth-strontium-tantalum oxide (SBT) ferroelectric material is performed by dissolving a bismuth compound in a first solvent to form a first solution, mixing a strontium compound and a tantalum compound to form a binary mixture, dissolving the binary mixture in a second solvent to form a second solution, mixing the first solution with the second solution to form a SBT precursor solution, evaporating the first and second solvents to form a SBT precursor material and subsequently sintering said SBT precursor material in the presence of oxygen.
    Type: Grant
    Filed: August 16, 1996
    Date of Patent: November 4, 1997
    Assignee: Sandia Corporation
    Inventor: Timothy J. Boyle
  • Patent number: 5681410
    Abstract: A method of producing a piezoelectric/electrostrictive actuator including a ceramic substrate and a piezoelectric/electrostrictive portion, including the steps of: superposing on each other a first and a second green sheet which give, by firing thereof, a first layer and a second layer of ceramic substrate, respectively, the first green sheet having at least one opening formed through a thickness thereof; firing the first and second green sheets to form the ceramic substrate such that the second layer cooperates with the at least one opening in the first layer to define at least one recess which has a bottom surface defining a thin-walled portion of the ceramic substrate; and forming the piezoelectric/electrostrictive portion on the thin-walled portion of the ceramic substrate.
    Type: Grant
    Filed: February 4, 1993
    Date of Patent: October 28, 1997
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takeuchi, Koji Kimura
  • Patent number: 5662782
    Abstract: An apparatus and method for manufacturing resonant elements such as piezoelectric elements, quartz resonators and other resonant elements while monitoring and regulating the resonance frequencies of the elements are disclosed. A radiation source such as an ion gun provides a plasma to selectively remove portions of an electrode on the resonant element to increase the resonance frequency. The distance between the radiation source and the electrode may be varied while monitoring the resonance frequency and the distance adjusted based on the measured resonance frequency. Different stages with increasing distances between different radiation sources and the resonant element to provide consecutively finer adjustment may be used to consecutively bombard the electrode with ions, with the resonant element being conveyed to the different stages. Oscillators and related devices using the resonant elements are also disclosed.
    Type: Grant
    Filed: February 24, 1995
    Date of Patent: September 2, 1997
    Assignee: Seiko Epson Corporation
    Inventors: Takeshi Gomi, Yukihiro Endo
  • Patent number: 5660877
    Abstract: A process for fabricating a fully dense ceramic preform for a piezoelectric or electrostrictive composite exhibiting anisotropic 3--3 connectivity. The process involves preparing a homogeneous slurry of a piezoelectric ceramic powder, a binder, dispersant, and a liquid medium. The slurry is freeze dried to form a ceramic preform having ceramic interconnected lamelli having greater connectivity in the Z direction than in the X and Y direction, and having interconnected interlamellar regions. The composite is fabricated by infiltrating the fully dense ceramic preform with an infiltrate phase in the interconnected interlamellar regions. The composite may be poled to produce a piezoelectric composite for electromechanical devices exhibiting anisotropic 3-3 connectivity.
    Type: Grant
    Filed: October 2, 1995
    Date of Patent: August 26, 1997
    Assignee: General Electric Company
    Inventors: Venkat Subramaniam Venkataramani, Lowell Scott Smith
  • Patent number: 5650362
    Abstract: An oriented conductive thin film useful as a thin film electrode or a thin film resistor may be made by coating a single crystal substrate with a metal oxide precursor solution containing an organometallic compound, and subjecting the coating layer to thermal decomposition, followed by annealing the coated substrate. The result is an epitaxial or oriented perovskite ABO.sub.3 structure oxide conductive thin film. A further layer of an epitaxial or oriented ABO.sub.3 type ferroelectric thin film can be formed on the conductive thin film.
    Type: Grant
    Filed: May 11, 1995
    Date of Patent: July 22, 1997
    Assignee: Fuji Xerox Co.
    Inventor: Keiichi Nashimoto
  • Patent number: 5643629
    Abstract: Method and apparatus for adjusting the electrical parameters of monolithic crystal filters having an electrode pattern that includes resonator electrodes and inter-resonator gap and constitutes two coupled resonators, based on thin-film deposition on the electrode pattern of one side of the filter through a single-aperture mask, with mask and filter movable relatively to each other during the adjustment process, such as to be able to guide said deposition in response to measurements of said electrical parameters to any area of said electrode pattern for the purpose of adjusting said parameters to their target values.
    Type: Grant
    Filed: June 30, 1992
    Date of Patent: July 1, 1997
    Inventor: Franz L. Sauerland
  • Patent number: 5639508
    Abstract: A method of producing a layered piezoelectric element for producing a pressure fluctuation within a cavity of an ink jet print head to eject ink from within the cavity, the production method comprising the steps of screen printing a slurry of powdered piezoelectric material to form a piezoelectric ceramic layer; screen printing a conductive paste to form an internal electrode layer on the piezoelectric ceramic layer; and repeating in alternation the steps of screen printing the slurry of powdered piezoelectric material and screen printing the conductive paste to obtain a layered body with piezoelectric ceramic layers and internal electrode layers layered in alternation.
    Type: Grant
    Filed: March 11, 1996
    Date of Patent: June 17, 1997
    Assignee: Brother Kogyo Kabushiki Kaisha
    Inventors: Yasuo Okawa, Yasuji Chikaoka, Atsuo Sakaida, Yoshihumi Suzuki, Yoshiyuki Ikezaki
  • Patent number: 5637346
    Abstract: A process for preparing a thin film of (Ba.sub.x Sr.sub.1-x)TiO.sub.3 is provided, which comprises adding to a solvent represented by formula (I-A)R.sup.1' OR.sup.2 OH (I-A)wherein R.sup.1' represents an aliphatic hydrocarbon group having two or more carbon atoms; and R.sup.2 represents a divalent aliphatic hydrocarbon group, two metallic alkoxide compounds represented by the formulae (II) and (III) or three metallic alkoxide compounds represented by formulae (II) to (IV):Ba(OR.sup.3).sub.2 (II)Ti(OR.sup.4).sub.4 (III)Sr(OR.sup.5).sub.2 (IV)wherein R.sup.3, R.sup.4 and R.sup.5 each represent an aliphatic hydrocarbon group, to make mixture, heating the mixture, applying the resulting mixture to a substrate to form a thin film, and then subjecting the material to heat treatment.
    Type: Grant
    Filed: October 19, 1994
    Date of Patent: June 10, 1997
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Hiroaki Moriyama, Keiichi Nashimoto
  • Patent number: 5631040
    Abstract: A piezoelectric/electrostrictive actuator comprising a substrate, a plurality of electrodes in the form of strips formed on at least one surface of the substrate such that the electrode strips are spaced from each other in a direction parallel to the substrate surface, and a piezoelectric/electrostrictive portion which is disposed between the adjacent strips of the electrodes in the spacing direction, and in contact with the adjacent electrode strips, so that the piezoelectric/electrostrictive portion produces a flexural displacement or force due to at least the longitudinal mode of converse piezoelectric or electrostrictive effect upon application of a voltage between the adjacent electrode strips.
    Type: Grant
    Filed: May 19, 1995
    Date of Patent: May 20, 1997
    Assignee: NGK Insulators, Ltd.
    Inventors: Yukihisa Takuchi, Masato Komazawa
  • Patent number: 5630949
    Abstract: Resonator fabricating method and apparatus employ the resonance conditions of the piezoelectric resonator itself to control an RF-powered plasma etching or deposition process. In its basic implementation, the apparatus does not require monitoring of the resonant frequency of the resonator as it is being trimmed. Rather, the resonator provides an impedance which changes as the plasma action changes the thickness of the resonator and thereby changes the resonant frequency of the piezoelectric resonator. The changing impedance in turn changes the rate of plasma action until the action substantially stops with the resonant frequency of the resonator substantially equal to the frequency of the RF source.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: May 20, 1997
    Assignee: TFR Technologies, Inc.
    Inventor: Kenneth M. Lakin
  • Patent number: 5626728
    Abstract: A piezoelectric device, such as a surface acoustic wave filter, comprises a piezoelectric film composed of a lead zirconium titanate compound applied to a substrate formed of silicon or gallium arsenide. The device includes an intermediate film between the piezoelectric film and the substrate and composed of a lead-free zirconium titanate compound to prevent interaction between lead oxide in the piezoelectric material and the material of the substrate that would otherwise cause spilling or adversely effect the electrical properties of the substrate. The piezoelectric device is made by first applying the film of the lead-free zirconium titanate compound and thereafter applying the film of the lead zirconium titanate compound. Preferably, the lead-free zirconium titanate film is applied by sputtering and annealed to densify the material and increase the dielectric constant prior to depositing the piezoelectric material.
    Type: Grant
    Filed: May 27, 1994
    Date of Patent: May 6, 1997
    Assignee: Motorola, Inc.
    Inventors: Ed S. Ramakrishnan, Wei-Yean Howng
  • Patent number: 5622748
    Abstract: A piezoelectric/electrostrictive actuator including a ceramic substrate, and at least one piezoelectric/electrostrictive actuator unit formed on at least a portion of at least one surface of the substrate, each piezoelectric/electrostrictive actuator unit having a first electrode film, a piezoelectric/electrostrictive film and a second electrode film which are laminated in the order of description, with the piezoelectric/electrostrictive actuator unit formed on the substrate by heat treatment.
    Type: Grant
    Filed: May 26, 1995
    Date of Patent: April 22, 1997
    Assignees: NGK Insulators, Ltd., Seiko Epson Corporation
    Inventors: Yukihisa Takeuchi, Koji Kimura, Masato Komazawa
  • Patent number: 5620740
    Abstract: A process for making an infra-red detector array wherein an array of m * n first electrodes is formed on a substrate and a layer of plastic material having a polarization sensitive to infra-red radiation is deposited over the electrodes. The layer is partitioned into individual films each over an associated first electrode and second electrodes are positioned on the films on the side opposite to the associated first electrodes.
    Type: Grant
    Filed: April 4, 1995
    Date of Patent: April 15, 1997
    Assignee: Servo Corporation of America
    Inventors: Shankar B. Baliga, George Rullman, Alan P. Doctor
  • Patent number: 5599588
    Abstract: The present invention concerns a process for obtaining metal halides, in particular rare earth and/or alkali earth halides. This process consists of forming a homogeneous solution by mixing one or more rare earth and/or alkali earth halogenoalkoxides in an anhydrous organic solvent, and hydrolyzing this solution. The novel materials are obtained at room temperature and are in powder, fibre, film or bulk material form.
    Type: Grant
    Filed: November 14, 1995
    Date of Patent: February 4, 1997
    Assignee: Eastman Kodak Company
    Inventor: Oliver J. C. Poncelet
  • Patent number: 5597610
    Abstract: An electric component includes an electric element and terminals connected and fixed with the electric element. The electric element and parts of the terminals are covered with a coating resin. A method for covering the electric component with the resin comprises a step of coating a repelling material for repelling a releasing agent on the terminals above a standard line which is the lowest limit of parts on the terminals that are planned to be covered with the coating resin, a step of coating a releasing agent for repelling the resin on the terminals below the standard line on the terminals, the releasing agent being repelled by the repelling material, and a step of coating the resin on the electric element from the standard line on the terminals by dipping the electric element into a melted resin.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: January 28, 1997
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Satoshi Miura
  • Patent number: 5593721
    Abstract: An organic silicon compound 10 is applied around vibrating electrodes 3a and 3b of a piezoelectric resonant element 1. A compound such as silane, chlorosilane, silazane, silthiane, siloxane, cyclosilane, cyclosilazane, cyclosilthiane, cyclosiloxane, silanol, or metallosilicone is used as the organic silicon compound 10. Around the piezoelectric resonant element 1 and the organic silicon compound 10, for example, an ultraviolet ray curing resin is applied, and the ultraviolet ray curing resin is cured, thereby a permeable film 11 is formed. A cavity 12 is formed around the vibrating electrodes 3a and 3b by dispersing the organic silicon compound 10 to the outside through the film 11. Around the film 11, for example, an outer coating resin is applied, and the outer coating resin is cured, thereby an outer coating material 13 is formed.
    Type: Grant
    Filed: June 1, 1995
    Date of Patent: January 14, 1997
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Muneyuki Daidai, Manabu Sumita
  • Patent number: 5571363
    Abstract: A method and device for selectively reducing the frequency-temperature shift of piezoelectric crystals. The piezoelectric device (100) includes a substrate (102), a piezoelectric element (106) and a temperature dependent interface structure (120) for beneficially stressing the piezoelectric element at a predetermined temperature range. The substrate (102), piezoelectric element (106) and temperature-dependent interface structure (120) define a piezoelectric package having a predetermined non-compensated third order Bechmann curve having a low temperature end and a high temperature end, with an inflection point therebetween, whereby the frequency-temperature shift is reducable on the third order Bechmann curve.
    Type: Grant
    Filed: August 15, 1995
    Date of Patent: November 5, 1996
    Assignee: Motorola, Inc.
    Inventors: Jill A. Brosig, Matt Laurich
  • Patent number: 5570225
    Abstract: A method for producing domain reversals at predetermined periods deep into a MgO-LN substrate or a MgO-LT substrate in a highly controllable manner without entailing the destruction of crystals of the substrate. Proton-exchanged regions are produced in a predetermined pattern on a unipolarized MgO-LN substrate, and a substrate having a doping level of MgO ranging between 3 mol. % and 9 mol. % is used as the MgO-LN substrate when these proton-exchanged regions are changed to localized domain reversals by applying an electric field to the proton-exchanged regions from a high voltage power source via a corona wire.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: October 29, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Akinori Harada
  • Patent number: 5568308
    Abstract: A method for producing domain reversals at predetermined periods deep into a MgO-LN substrate or a MgO-LT substrate in a highly controllable manner without entailing the destruction of crystals of the substrate. Proton-exchanged regions are produced in a predetermined pattern on a unipolarized MgO-LN substrate, and a substrate having a doping level of MgO ranging between 3 mol. % and 9 mol. % is used as the MgO-LN substrate when these proton-exchanged regions are changed to localized domain reversals by applying an electric field to the proton-exchanged regions from a high voltage power source, e.g. via a corona wire.
    Type: Grant
    Filed: February 17, 1994
    Date of Patent: October 22, 1996
    Assignee: Fuji Photo Film Co., Ltd.
    Inventor: Akinori Harada
  • Patent number: 5560090
    Abstract: A method of fabricating an ink jet print head which jets ink through an ink jet nozzle by pressurizing the ink supplied to a pressure chamber from an ink supplying portion, including applying flowable resin on a surface of a piezoelectric member polarized along a thickness thereof; forming a low rigidity member having a rigidity less than that of the piezoelectric member by curing the resin; grinding a surface of the low rigidity member; forming a plurality of grooves extending from the surface of the low rigidity member to an inside of the piezoelectric member; forming electrodes on the entire inner surface of the grooves; and sticking a top plate on the ground surface to close an opening of the grooves, thereby forming a plurality of pressure chambers communicating with an ink supplying portion and the ink jet nozzle. Since the low rigidity member is cured before it is ground, the proportion of the height of the low rigidity member and the piezoelectric member is equalized.
    Type: Grant
    Filed: August 18, 1994
    Date of Patent: October 1, 1996
    Assignee: Kabushiki Kaisha TEC
    Inventors: Shigeo Komakine, Kuniaki Ochiai
  • Patent number: 5549926
    Abstract: A method of manufacturing an electronic part includes a step of preparing a molten resin bathtub used for coating the outer surface of the electronic part. On a surface of the resin in the molten resin bathtub, a layer of a surface-active agent is formed. The electronic part body is dipped via the solvent layer into the molten resin bathtub. After coating the electronic part body with the molten resin, the electronic part body is removed from the molten resin bathtub. The molten resin is cured by heating and the resin layer is formed on the electronic part body.
    Type: Grant
    Filed: October 30, 1995
    Date of Patent: August 27, 1996
    Assignee: Murata Manufacturing Co., Ltd.
    Inventor: Makoto Miyamoto
  • Patent number: 5518952
    Abstract: Methods of coating piezoelectric substrates with substantially uniform layers of a semi-conducting material are disclosed including placing the substrate in a heated deposition chamber at reduced pressure and depositing a layer of semiconducting material on the substrate by thermally activated chemical vapor deposition, including admitting a gas bearing the semi-conducting material into the chamber at a pressure of between about 13 and 200 Pa and a temperature of between about 300.degree. and 700.degree.C. so that a layer of semi-conducting material having a desired smoothness is obtained.
    Type: Grant
    Filed: September 20, 1994
    Date of Patent: May 21, 1996
    Assignee: Markpoint Development AB
    Inventors: Jiri Vonasek, deceased, Stig G. Larsson, Ove Andersson
  • Patent number: 5517739
    Abstract: A Polarization-Sensitive Shear Wave Transducer Structure utilizes a 4 part MuSLE electrode formed on a top surface of a dilithium tetraborate (Li.sub.2 B.sub.4 O.sub.7) substrate that acts as a transducer forming a body. Electrode gaps of the MuSLE electrode are aligned along the X.sub.1 ' and X.sub.3 ' axes of the dilithium tetraborate substrate. The substrate orientation is chosen along the degeneracy locus occurring in the primitive region between the end points (YXl) 19.degree. and (YXw) 27.degree.. The body is bonded to a test object and segments of the MuSLE electrode are coupled to a power source allowing an excitation voltage to create a lateral-field driving a shear wave of selectable polarization. The segments of the MuSLE electrode can also be coupled to a means for detecting a voltage allowing a shear wave incident on the transducer to be detected.
    Type: Grant
    Filed: October 7, 1994
    Date of Patent: May 21, 1996
    Assignee: The United States of America as represented by the Secretary of the Army
    Inventor: John A. Kosinski
  • Patent number: 5500988
    Abstract: In the particular embodiments described in the specification, a thin-film PZT piezoelectric transducer ink jet head is prepared by oxidizing one surface of a silicon wafer to provide a dielectric layer, forming electrodes on the layer by photoresist processing techniques, depositing one or more layers of perovskite-seeded PZT material to provide a thin-film piezoelectric layer having a thickness in the range of 1-25 microns, forming another pattern of electrodes on the surface of the PZT layer by photoresist techniques, and selectively etching the silicon substrate in the region of the electrodes to provide an ink chamber. Thereafter, an orifice plate is affixed to the substrate to enclose the ink chambers and provide an ink orifice for each of the chambers. An ink jet head having chambers 3.34 mm long by 0.17 mm wide by 0.15 mm deep and orifices spaced by 0.305 mm is provided.
    Type: Grant
    Filed: June 13, 1994
    Date of Patent: March 26, 1996
    Assignee: Spectra, Inc.
    Inventors: Edward R. Moynihan, Paul A. Hoisington, David W. Gailus
  • Patent number: 5471721
    Abstract: Monolithic, internally asymmetrically stress biased electrically active ceramic devices and a method for making same is disclosed. The first step in the method of the present invention is to fabricate a ceramic element having first and second opposing surfaces. Next, only the first surface is chemically reduced by heat treatment in a reducing atmosphere. This produces a concave shaped, internally asymmetrically stress biased ceramic element and an electrically conducting, chemically reduced layer on the first surface which serves as one of the electrodes of the device. Another electrode can be deposited on the second surface to complete the device. In another embodiment of the present invention two dome shaped ceramic devices can be placed together to form a completed clamshell structure or an accordion type structure. In a further embodiment, the clamshell or accordion type structures can be placed on top of one another.
    Type: Grant
    Filed: February 23, 1993
    Date of Patent: December 5, 1995
    Assignee: Research Corporation Technologies, Inc.
    Inventor: Gene H. Haertling
  • Patent number: 5454146
    Abstract: A microactuator having a piezoelectric material and a drive electrode formed adjacent to the piezoelectric material is manufactured by forming an electroplating electrode on a substrate and providing a photosensitive material layer on the substrate on which the electroplating electrode is formed. The photosensitive material layer is exposed in a desired pattern. The exposed photosensitive material layer is developed to partially remove the exposed photosensitive material layer. A metal with electroplating is filled in a substrate portion from which the photosensitive material layer is removed, so that a drive electrode is formed. A remaining photosensitive material layer is removed. Finally, a piezoelectric material is selectively filled in a substrate portion adjacent to the drive electrode.
    Type: Grant
    Filed: November 10, 1993
    Date of Patent: October 3, 1995
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takayuki Yagi, Hiroshi Takagi, Masahiro Fushimi, Tomoko Murakami
  • Patent number: 5453294
    Abstract: In the production of ferroelectric PZT or PLZT thin film by the sol-gel method, application of precursor solution (sol) onto a substrate is followed by heat-treatment for pyrolysis at 150.degree.-250.degree. C., 250.degree.-359.degree. C., or 450.degree.-550.degree. C., and further firing for crystallization at 500.degree.-800.degree. C., whereby crystal orientation in the direction of the (111) plane, or the (111) and (100) planes, or the (100) and (200) planes can be effected.
    Type: Grant
    Filed: April 16, 1993
    Date of Patent: September 26, 1995
    Assignee: Mitsubishi Materials Corporation
    Inventors: Katsumi Ogi, Nobuyuki Soyama, Akihiko Mieda
  • Patent number: 5404628
    Abstract: The method comprises decomposing an original resonator within a network into a pair of series connected resonators to add an additional connecting electrode to the network. The pair of resonators are series connected by a shared electrode. To preserve the original electrical characteristics of the network, the composite characteristics of the series connected resonators are chosen to match those of the original resonator. With this method, the additional electrode is placed on a surface of the piezoelectric material opposing the surface to which the shared electrode is mounted. The method allows for the addition of an electrode to a piezoelectric resonator-based network so that the electrodes which connect the network to other circuitry may be placed where desired. This may be on the upper surface of the piezoelectric material for connection to discrete components or on the lower, buried surface for connection to buried layers of an adjacent integrated circuit.
    Type: Grant
    Filed: April 14, 1993
    Date of Patent: April 11, 1995
    Assignee: TFR Technologies, Inc.
    Inventor: Richard S. Ketcham
  • Patent number: 5401544
    Abstract: A surface acoustic wave device which can operate at a higher frequency range is produced by irradiation with a focused ion beam to produce a narrower electrode width and narrower spacing width between neighboring electrodes in contact with a piezoelectric body, without degrading the reliability of the device. The surface acoustic wave device includes a piezoelectric body 3 and interdigital electrodes 2a and 2b in close contact with the piezoelectric body 3 and formed by using the focused ion beam. In order to increase the frequency of the device, the piezoelectric body 3 may be formed on a substrate 1, for example of diamond.
    Type: Grant
    Filed: August 19, 1993
    Date of Patent: March 28, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hideaki Nakahata, Shinichi Shikata, Akihiro Hachigo, Naoji Fujimori
  • Patent number: 5395663
    Abstract: There is provided a process for producing a dielectric thin film of a perovskite oxide on a substrate by a vapor-deposition process which includes vaporizing the oxide and irradiating the oxide vapor or the substrate with a laser beam.There is also provided a pyroelectric type of sensor comprising: a MOS element including a drain electrode, a source electrode, a gate electrode and an Si semiconductor and a film of a ferroelectric or pyroelectric material formed on the drain electrode, the drain electrode being made of a material which exhibits a good ohmic contact with Si or SiO.sub.2 and has a lattice constant close to that of ferroelectric or pyroelectric material.
    Type: Grant
    Filed: April 26, 1993
    Date of Patent: March 7, 1995
    Assignee: Kawasaki Jukogyo Kabushiki Kaisha
    Inventors: Hitoshi Tabata, Osamu Murata, Junzo Fujioka, Shunichi Minakata, Shichio Kawai, Tomoji Kawai
  • Patent number: 5390401
    Abstract: A surface acoustic wave device is so manufactured that it's reliability is increased and so that it is surface-mountable with no requirement for packaging. The surface acoustic wave device (20) has a pair of opposite interdigital electrodes (2a, 2b) and a piezoelectric member (4) in close contact with the interdigital electrodes (2a, 2b). A portion located between the pair of interdigital electrodes (2a, 2b) propagates surface acoustic waves. This device (20) is characterized by an air bridge (13) covering the portion of the piezoelectric member (4) for propagating surface acoustic waves and the pair of interdigital electrodes (2a, 2b). The air bridge (13), may be provided with an insulating film (14) which is not in contact with the piezoelectric member (4).
    Type: Grant
    Filed: August 6, 1993
    Date of Patent: February 21, 1995
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Shinichi Shikata, Hideaki Nakahata, Akihiro Hachigo, Naoji Fujimori
  • Patent number: 5391393
    Abstract: A method for making a semiconductor device having an anhydrous ferroelectric thin-film obtained from an anhydrous sol-gel solution. An anhydrous PZT sol-gel solution is provided, wherein the sol-gel solution is prepared from lead (II) acetate anhydrous, which is heated with zirconium and titanium precursors to form a gel. The sol-gel solution is prepared without hydrolyzing the solution to obtain precursor complexes which do not contain water. The sol-gel is then applied to a semiconductor substrate and crystallized to form a ferroelectric thin-film. In a preferred embodiment, one or more steps of preparing the sol-gel solution, applying the sol-gel solution, and crystallizing the sol-gel solution are carried out in the presence of an oxygen-containing ambient.
    Type: Grant
    Filed: August 19, 1993
    Date of Patent: February 21, 1995
    Assignee: Motorola, Inc.
    Inventor: Papu D. Maniar
  • Patent number: 5374449
    Abstract: A monolithic piezoelectric key structure having a piezoelectric layer adherently connected between two conductive areas. The piezoelectric layer is applied as a fluid on the base conductive area and transformed into a coherent solid adhering to the base conductive area. The other conductive area is adherently formed on the piezoelectric layer. The monolithic structure is polarized.
    Type: Grant
    Filed: June 22, 1993
    Date of Patent: December 20, 1994
    Assignee: Algra Holding AG
    Inventors: Albert Buhlmann, Hans Schenk
  • Patent number: 5355568
    Abstract: A surface acoustic wave device having a diamond layer, a piezoelectric layer and a comb-like electrode, in which the piezoelectric layer and the comb-like electrode are formed on a surface of the diamond layer, which surface has been contacted to a substrate used in the formation of the diamond layer by a vapor phase growth method, which device has high stability and can be produced economically.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: October 18, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Takahiro Imai, Hideaki Nakahata, Akihiro Hachigo, Naoji Fujimori
  • Patent number: 5342648
    Abstract: Amorphous ferroelectric materials are formed by a sol-gel type process and the ferroelectric properties stabilized by complete hydrolysis and polycondensation, and extraction of residual organic materials, preferably by heating at temperatures below the temperature at which crystallization may occur. Stable solutions of metal alkoxides are prepared by reacting or dissolving a metal alkoxide in alcohol such as absolute ethanol. The solution may be spincast on essentially any substrate, conductor or nonconductor, crystalline or amorphous, transparent or opaque, and even including plastics. Hydrolysis and polycondensation occur in situ to deposit an amorphous ferroelectric film. Residual alcohol is extracted by heating below the temperature at which crystallization occurs. Such films show P-E hysteresis loops and pyroelectric current. Such ferroelectric thin films are useable in electronic, opto-electronic and optical devices.
    Type: Grant
    Filed: September 23, 1992
    Date of Patent: August 30, 1994
    Assignee: The Regents of the Universty of California
    Inventors: John D. MacKenzie, Ren Xu, Yuhuan Xu
  • Patent number: 5320865
    Abstract: A method of manufacturing a surface acoustic wave device which has a smaller insertion loss and which operates at higher frequency than a conventional surface acoustic wave device is provided. The surface acoustic wave device includes a substrate, a diamond layer formed on the substrate, a piezoelectric layer formed on the diamond layer, and electrodes formed on any of the substrate, the diamond layer and the piezoelectric layer. The piezoelectric layer is formed by the laser ablation method. The insertion loss of this acoustic wave device is small even in a high frequency range of several hundreds MHz to GHz. Therefore, the device can be used as a frequency filter, a resonator, a delay line, a convolver, a correlator and the like.
    Type: Grant
    Filed: September 16, 1992
    Date of Patent: June 14, 1994
    Assignee: Sumitomo Electric Industries, Ltd.
    Inventors: Hideaki Nakahata, Shinichi Shikata, Akihiro Hachigo, Naoji Fujimori
  • Patent number: 5295288
    Abstract: A solid state motor includes a plurality of piezoelectric elements assembled in a stack. Each element has two opposing planar surfaces. A plurality of electrodes each has a planar section contacting the planar surfaces of two adjacent elements in the stack. A silicone adhesive is adapted to adhere to the piezoelectric elements. A plurality of alumina particles are disposed in the silicone adhesive. A protective housing cylindrically encases the combination of the stack, electrodes, and silicone adhesive.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: March 22, 1994
    Assignee: Caterpillar Inc.
    Inventors: Chuong Q. Dam, Kurtis C. Kelley
  • Patent number: 5271956
    Abstract: A process is disclosed of forming a film of a ternary metal fluoride in which there is combined a solvent solution, a mixture of metallo-ogranic compounds, and an organic fluoride to form a casting liquid. The casting liquid is then coated by a method such as dip coating or spin coating to form a coating on a substrate. The coated substrate is then heated to decompose the metallo-organic compounds and organic fluoride resulting in recovery of a termary metal fluoride coated substrate. The ternary metal fluorides formed are fluorides of at least one alkaine earth metal and at least one fourth period divalent transition metal having an atomic number of from 22 to 30 inclusive.
    Type: Grant
    Filed: December 30, 1991
    Date of Patent: December 21, 1993
    Assignee: Eastman Kodak Company
    Inventor: Gustavo R. Paz-Pujalt
  • Patent number: 5271955
    Abstract: A method for making a semiconductor device having an anhydrous ferroelectric thin film obtained from an anhydrous sol-gel solution. An anhydrous PZT sol-gel solution is prepared from Lead (II) Acetate Anhydrous which is thermally reacted with Zirconium and Titanium precursors to form a gel condensate. The sol-gel condensate is prepared without hydrolyzing the sol-gel solution to obtain precursor complexes which do not contain water. The formulation of the sol-gel exclusively by thermal condensation and in the absence of hydrolysis yields an anhydrous amorphous sol-gel having a uniform condensate composition. The anhydrous PZT thin film formed by the anhydrous sol-gel exhibits improved durability and substantially complete low-temperature conversion to the perovskite crystalline phase.
    Type: Grant
    Filed: April 6, 1992
    Date of Patent: December 21, 1993
    Assignee: Motorola, Inc.
    Inventor: Papu Maniar
  • Patent number: 5265315
    Abstract: A thin-film transducer ink jet head is prepared by oxidizing one surface of a silicon wafer to provide a dielectric layer, forming electrodes on the layer by photoresist processing techniques, depositing one or more layers of PZT material to provide a thin-film piezoelectric layer having a thickness in the range of 1-25 microns, forming another pattern of electrodes on the surface of the PZT layer by photoresist techniques, and selectively etching the silicon substrate in the region of the electrodes to provide an ink chamber. Thereafter, an orifice plate is affixed to the substrate to enclose the ink chambers and provide an ink orifice for each of the chambers. An ink jet head having chambers 3.34 mm long by 0.17 mm wide by 0.15 mm deep and orifices spaced by 0.305 mm is provided.
    Type: Grant
    Filed: November 20, 1990
    Date of Patent: November 30, 1993
    Assignee: Spectra, Inc.
    Inventors: Paul A. Hoisington, Edward R. Moynihan, David W. Gailus
  • Patent number: 5254504
    Abstract: A method of manufacturing ferroelectric sensors having piezoelectric and pyroelectric properties are provided. These sensors include a semiconductor transistor having a gate and a surface layered with an integral film comprising a substantially poled ferroelectric polymer. The integral film is electrically connected to ground or a voltage source and to the gate of the semiconductor transistor. The preferred integral film is deposited on the semiconductor transistor using spin coating techniques. Extremely sensitive acoustic imaging sensors and the like can be produced in accordance with the invention which have high voltage sensitivity and better acoustic impedance match with body tissues and water.
    Type: Grant
    Filed: September 5, 1991
    Date of Patent: October 19, 1993
    Assignee: Trustees of the University of Pennsylvania
    Inventors: Jan Van der Spiegel, Antinino Fiorillo
  • Patent number: 5230921
    Abstract: A piezo-electric flexible membrane is formed by treating a perfluorinated membrane in order to produce a membrane having an electrical resistance greater than 1.times.10.sup.9 ohms. The resultant piezo-electric membrane may be used as an ultrasound transducer.
    Type: Grant
    Filed: August 4, 1992
    Date of Patent: July 27, 1993
    Assignee: Blacktoe Medical, Inc.
    Inventors: James R. Waltonen, Ronald W. Schutz
  • Patent number: 5228176
    Abstract: An improved ultrasonic transducer for a catheter tip has a thin strip of piezoelectric polymer film formed into a spiral ring and adhesively mounted on the support structure near the catheter tip. Electrical connection between the back face of the film and the support structure negative electrode is via capacitive coupling. Connection to the front face of the film is via a wire connected to the positive electrode of the catheter. A further embodiment suitable for a needle transducer is formed by coating the tip with a solution of PVDF co-polymer to form the actual transducer.
    Type: Grant
    Filed: September 19, 1991
    Date of Patent: July 20, 1993
    Assignee: Telectronics Pacing Systems, Inc.
    Inventors: Tuan Bui, Saad Nasr
  • Patent number: 5185178
    Abstract: An array of densely packed discrete metal microspheres which may be deformable and electrically conductive may be formed on a substrate by a method including the steps of providing a substrate having a depositing surface in the chamber forming a metal vapor in the chamber and depositing the metal vapor on the depositing surface, the depositing surface having a temperature at or above the melting point of the metal.
    Type: Grant
    Filed: May 29, 1991
    Date of Patent: February 9, 1993
    Assignee: Minnesota Mining and Manufacturing Company
    Inventor: David C. Koskenmaki
  • Patent number: 5152864
    Abstract: Interdigital transducers and reflectors are formed on a piezoelectric substrate from an aluminum film. The aluminum film is formed by electron beam deposition at a film forming rate which is controlled to be at least 20 .ANG. per second. The aluminum film formed in this way is crystallographically oriented in a constant direction, whereby stressmigration of the aluminum film is suppressed.
    Type: Grant
    Filed: July 18, 1991
    Date of Patent: October 6, 1992
    Assignee: Murata Manufacturing Co., Ltd.
    Inventors: Hideharu Ieki, Atsushi Sakurai, Koji Kimura
  • Patent number: 5133990
    Abstract: A technique of providing numerous distinct conductive patterns on a piezoelectric substrate is accomplished using only two masking apparatus. One masking apparatus defines a common portion or structure for each of the patterns. The second masking apparatus defines numerous distinct patterns, each corresponding to a different alignment position with respect to the common structure already formed on the substrate. One application for this technique is in economic production of coded SAW devices which may serve as coding or decoding devices, filters, or correlators, each of the SAW devices having a different individual code.
    Type: Grant
    Filed: April 5, 1990
    Date of Patent: July 28, 1992
    Assignee: Crystal Technology, Inc.
    Inventors: Bernd W. Fleischmann, Donald R. Allen
  • Patent number: 5129132
    Abstract: An integrated scanning tunneling microscope and an integrated piezoelectric transducer and methods for making both. The device consists of one or two arm piezoelectric bimorph cantilevers formed by micromachining using standard integrated circuit processing steps. These cantilevers are attached to the substrate at one area and are free to move under the influence of piezoelectric forces which are caused by the application of appropriate voltages generated by control circuitry and applied to pairs of electrodes formed as an integral part of the bimorph cantilever structure. The electric fields caused by the control voltages cause the piezoelectric bimorphs to move in any desired fashion within ranges determined by the design. The bimorph cantilevers have tips with very sharp points formed thereon which are moved by the action of the control circuit and the piezoelectric bimorphs so to stay within a very small distance of a conducting surface.
    Type: Grant
    Filed: January 10, 1990
    Date of Patent: July 14, 1992
    Assignee: Board of Trustees of the Leland Stanford Jr., University
    Inventors: Mark Zdeblick, Thomas R. Albrecht
  • Patent number: 5116643
    Abstract: A method to produce thin films suitable for fabricating ferroelectric thin films. The method provides for selection of the predetermined amounts of lead, lanthanum, zirconium, and titanium precursors which are soluble in different solvents. Dissolving predetermined amounts of the precursors in their respective solvents in proportions such that hydrolyze reaction rate for each metal precursor will be approximately equal. Preferably, the reaction is performed under an inert atmosphere at from about 350 mmHg to 650 mmHg pressure. The precursors and solvents are mixed, and water is added to begin a hydrolysis reaction. After the hydrolysis the solution is heated to drive off the excess water and solvent to promote the formation of a sol-gel. The sol-gel is then applied to a thin substrate and sintered to produce the ferroelectric film.
    Type: Grant
    Filed: December 19, 1990
    Date of Patent: May 26, 1992
    Assignee: National Semiconductor Corporation
    Inventors: William D. Miller, Leo N. Chapin