Niobate, Vanadate, Or Tantalate Containing {c30b 29/30} Patents (Class 117/948)
  • Patent number: 11937510
    Abstract: A piezoelectric ceramic containing no lead as a constituent element is provided. Coefficient of variation C.V. of grain size of grains contained in the piezoelectric ceramic is 35% or less, and an image quality (IQ) image obtained by analyzing a cross section of the piezoelectric ceramic by an electron backscatter diffraction (EBSD) method shows that at least one of the grains has a grain size of 3 ?m to 5 ?m and an area ratio of a domain in said at least one of the grains is 85% or more.
    Type: Grant
    Filed: September 29, 2020
    Date of Patent: March 19, 2024
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Tomohiro Harada, Yuuhei Ueyama
  • Patent number: 11852953
    Abstract: A highly-efficient ridge waveguide includes a base substrate of a single-crystal and a core substrate made of a nonlinear optical medium, the base substrate and the core substrate being directly bonded, and includes a thin film layer formed on a surface of the core substrate on the upper side of a periodically polarization-reversed structure, and becomes a wavelength conversion element. A direct bonding method through thermal diffusion is applied to bonding. The core substrate has a ridge structure formed in a light propagating direction and a reversed structure formed by processing this. A surface of the core substrate is ground and a thin film layer is formed on the ground surface. A core formed by digging a core layer of the core substrate in an unbonded state is provided on an upper surface of an undercladding layer of the base substrate in a bonded state. Two side surfaces of the core are in contact with an air layer.
    Type: Grant
    Filed: December 3, 2019
    Date of Patent: December 26, 2023
    Assignee: NIPPON TELEGRAPH AND TELEPHONE CORPORATION
    Inventors: Takeshi Umeki, Takushi Kazama, Takahiro Kashiwazaki, Koji Embutsu, Osamu Tadanaga, Asuka Inoue, Ryoichi Kasahara
  • Patent number: 11713520
    Abstract: An integrated die and crucible system used an integrated die and crucible assembly that allows for improved sapphire sheet growing as result of targeted heat features and controls of the integrated die and crucible system and corresponding systems used to form the integrated die and crucible assembly, which include in part heat plugs, as well specific wall thicknesses about the die and crucibles.
    Type: Grant
    Filed: February 8, 2022
    Date of Patent: August 1, 2023
    Assignee: Sapphire Systems, Inc.
    Inventors: John Outwater, Bradford Shattuck Collins
  • Patent number: 11581482
    Abstract: A piezoelectric ceramic, which does not contain lead as a constituent element, is characterized in that: its primary component is a perovskite compound expressed by the composition formula (Bi0.5?x/2Na0.5?x/2Bax)(Ti1?yMny)O3 (where 0.01?x?0.25, 0.001?y?0.020); and the coefficient of variation (CV) in grain size among the grains contained therein is 35 percent or lower. The piezoelectric ceramic presents an improved dielectric loss tangent tan ?.
    Type: Grant
    Filed: February 25, 2020
    Date of Patent: February 14, 2023
    Assignee: TAIYO YUDEN CO., LTD.
    Inventors: Yuuhei Ueyama, Tomohiro Harada, Hiroyuki Shimizu, Sumiaki Kishimoto, Yukihiro Konishi
  • Patent number: 11561421
    Abstract: Various embodiments of the present technology enable growth of a-axis oriented barium titanate (BTO) films by inserting a relaxed strain control layer having a larger lattice constant than the c-axis of BTO and a similar thermal expansion mismatch. As a result, in-plane tensile stress causes BTO to grow with its ferroelectric polarization in-plane. Some embodiments allow for BTO films to immediately be grown on silicon with a-axis orientation, and without the need to create thick layers for relaxation. Using various embodiments of the present technology, the BTO can be grown in-plane with minimal dislocation density that is confined to the interface region.
    Type: Grant
    Filed: June 25, 2020
    Date of Patent: January 24, 2023
    Assignee: Board of Regents, The University of Texas System
    Inventors: Alexander A. Demkov, Marc Reynaud, Agham Posadas
  • Patent number: 10367138
    Abstract: The output voltage of an MRAM is increased by means of an Fe(001)/MgO(001)/Fe(001) MTJ device, which is formed by microfabrication of a sample prepared as follows: A single-crystalline MgO (001) substrate is prepared. An epitaxial Fe(001) lower electrode (a first electrode) is grown on a MgO(001) seed layer at room temperature, followed by annealing under ultrahigh vacuum. A MgO(001) barrier layer is epitaxially formed on the Fe(001) lower electrode (the first electrode) at room temperature, using a MgO electron-beam evaporation. A Fe(001) upper electrode (a second electrode) is then formed on the MgO(001) barrier layer at room temperature. This is successively followed by the deposition of a Co layer on the Fe(001) upper electrode (the second electrode). The Co layer is provided so as to increase the coercive force of the upper electrode in order to realize an antiparallel magnetization alignment.
    Type: Grant
    Filed: February 9, 2017
    Date of Patent: July 30, 2019
    Assignees: JAPAN SCIENCE AND TECHNOLOGY AGENCY, NATIONAL INSTITUTE OF ADVANCED INDUSTRIAL SCIENCE AND TECHNOLOGY
    Inventor: Shinji Yuasa
  • Patent number: 9287323
    Abstract: A perpendicular magnetoresistive element comprises anovel buffer layer provided on a surface of the recording layer, which is opposite to a surface of the recording layer where the tunnel barrier layer is provided, wherein at least the portion of the buffer layer interfacing to the recording layer contains a rocksalt crystal structure having the (100) plane parallel to the substrate plane and at least a portion of the buffer layer comprises a doped element having conductivity enhancement and the perpendicular resistance of the buffer layer is relatively small than that of the tunnel barrier layer. The invention preferably includes materials, configurations and processes of perpendicular magnetoresistive elements suitable for perpendicular spin-transfer torque MRAM applications.
    Type: Grant
    Filed: January 7, 2014
    Date of Patent: March 15, 2016
    Inventor: Yimin Guo
  • Patent number: 8597535
    Abstract: A ternary single crystal relaxor piezoelectric of PMN-PZ-PT grown from a novel melt using the Vertical Bridgeman method. The ternary single crystals are characterized by a Curie temperature, Tc, of at least 150° C. and a rhombohedral to tetragonal phase transition temperature, Trt, of at least about 110° C. The ternary crystals further exhibit a piezoelectric coefficient, d33, in the range of at least about 1200-2000 pC/N.
    Type: Grant
    Filed: May 16, 2011
    Date of Patent: December 3, 2013
    Assignee: TRS Technologies, Inc.
    Inventors: Jun Luo, Wesley Hackenberger
  • Patent number: 8142678
    Abstract: A perovskite type oxide of a single crystal structure or a uniaxial-oriented crystal structure is represented by ABO3. Site A includes Pb as a main component and site B includes a plurality of elements. The perovskite type oxide includes a plurality of crystal phases selected from the group consisting of tetragonal, rhombohedral, orthorhombic, cubic, pseudo-cubic and monoclinic systems and the plurality of crystal phases are oriented in the direction of <100>.
    Type: Grant
    Filed: August 7, 2006
    Date of Patent: March 27, 2012
    Assignee: Canon Kabushiki Kaisha
    Inventors: Takanori Matsuda, Katsumi Aoki, Toshihiro Ifuku, Kenichi Takeda, Tetsuro Fukui, Hiroshi Funakubo, Shintaro Yokoyama
  • Patent number: 8021482
    Abstract: A method for eliminating precipitates contained in an II-VI solid semiconductor material, in which the solid semiconductor material is a congruent sublimation solid semiconductor material, the method including: providing an inert gas flow; heating the solid semiconductor material under the inert gas flow up to a temperature T, between a first temperature T1, corresponding to compound II-VI/element VI eutectic, and a second temperature T2, corresponding to maximum congruent sublimation temperature; maintaining the solid semiconductor material at this temperature T under a neutral gas flow for a time period sufficient to eliminate the precipitates; cooling the solid semiconductor material under the inert gas flow from temperature T to ambient temperature, at a rate such that, during the cooling, the solid semiconductor material merges with its congruent sublimation line; and recovering a precipitate-free solid semiconductor material.
    Type: Grant
    Filed: September 6, 2007
    Date of Patent: September 20, 2011
    Assignee: Commissariat a l'Energie Atomique
    Inventor: Bernard Pelliciari
  • Patent number: 7972527
    Abstract: A ternary single crystal relaxor piezoelectric grown from a novel melt using the Vertical Bridgeman method. The ternary single crystals are characterized by a Curie temperature, Tc, of at least 150° C. and a rhombohedral to tetragonal phase transition temperature, Trt, of at least about 110° C. The ternary crystals further exhibit a piezoelectric coefficient, d33, in the range of at least about 1200-2000 pC/N.
    Type: Grant
    Filed: January 31, 2008
    Date of Patent: July 5, 2011
    Assignee: TRS Technologies, Inc.
    Inventors: Jun Luo, Wesley S. Hackenberger
  • Patent number: 7674737
    Abstract: An optical medium having a high refractive index without anisotropy and a wide transmission wavelength is obtained. The cubic crystal material is ??O3, where ? is at least one of K, Ba, Sr, Ca, and ? is at least one of Ta, Ti. Optimally, the cubic crystal material is KTa1-xNbxO3, where composition x is 0?x?0.35. This composition enables to raise refractive index while its phase transition temperature is below a room temperature.
    Type: Grant
    Filed: June 22, 2005
    Date of Patent: March 9, 2010
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Kazuo Fujiura, Tadayuki Imai, Masahiro Sasaura, Kouichirou Nakamura
  • Patent number: 7575777
    Abstract: A method for manufacturing a potassium niobate deposited body includes: forming a buffer layer above a substrate composed of an R-plane sapphire substrate; forming above the buffer layer a potassium niobate layer or a potassium niobate solid solution layer that epitaxially grows in a (100) orientation in a pseudo cubic system expression; and forming an electrode layer above the potassium niobate layer or the potassium niobate solid solution layer, wherein a (100) plane of the potassium niobate layer or the potassium niobate solid solution layer is formed to tilt with a [11-20] direction vector as a rotation axis with respect to an R-plane (1-102) of the R-plane sapphire substrate.
    Type: Grant
    Filed: July 31, 2008
    Date of Patent: August 18, 2009
    Assignee: Seiko Epson Corporation
    Inventors: Takamitsu Higuchi, Taku Aoyama
  • Patent number: 7544248
    Abstract: In a process for manufacturing a LT substrate from a LT crystal, after growing the crystal, a LT substrate in ingot form is imbedded in carbon power, or is place in a carbon vessel, and heat treated is conducted at a maintained temperature of between 650° C. and 1650° C. for at least 4 hours, whereby in a lithium tantalate (LT) substrate, sparks are prevented from being generated by the charge up of an electric charge on the substrate surface, and thereby destruction of a comb pattern formed on the substrate surface and breaks or the like in the LT substrate are prevented.
    Type: Grant
    Filed: August 14, 2007
    Date of Patent: June 9, 2009
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Tomio Kajigaya, Takashi Kakuta
  • Patent number: 7544247
    Abstract: In a process for manufacturing a LT substrate from a LT crystal, after growing the crystal, a LT substrate in ingot form is imbedded in carbon power, or is place in a carbon vessel, and heat treated is conducted at a maintained temperature of between 650° C. and 1650° C. for at least 4 hours, whereby in a lithium tantalate (LT) substrate, sparks are prevented from being generated by the charge up of an electric charge on the substrate surface, and thereby destruction of a comb pattern formed on the substrate surface and breaks or the like in the LT substrate are prevented.
    Type: Grant
    Filed: May 9, 2007
    Date of Patent: June 9, 2009
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Tomio Kajigaya, Takashi Kakuta
  • Patent number: 7544246
    Abstract: In a process for manufacturing a LT substrate from a LT crystal, after growing the crystal, a LT substrate in ingot form is imbedded in carbon power, or is place in a carbon vessel, and heat treated is conducted at a maintained temperature of between 650° C. and 1650° C. for at least 4 hours, whereby in a lithium tantalate (LT) substrate, sparks are prevented from being generated by the charge up of an electric charge on the substrate surface, and thereby destruction of a comb pattern formed on the substrate surface and breaks or the like in the LT substrate are prevented.
    Type: Grant
    Filed: August 22, 2006
    Date of Patent: June 9, 2009
    Assignee: Sumitomo Metal Mining Co., Ltd.
    Inventors: Tomio Kajigaya, Takashi Kakuta
  • Patent number: 7399428
    Abstract: Embodiments of the present invention are directed to compositions and processing methods of rare-earth vanadate based materials that have high emission efficiency in a wavelength range of 480 to 700 nm with the maximum intensity at 535 nm (bright yellow) under UV, X-ray and other forms of high-energy irradiation. Embodiments of the present invention are directed to general chemical compositions of the form (Gd1-xAx)(V1-yBy)(O4-zCz), where A is selected from the group consisting of Bi, Tl, Y, La, Ce, Pr, Nd, Pm, Sm, Eu, Tb, Dy, Ho, Er, Tm, Yb, and Lu for 0<x<0.2; B is Ta, Nb, W, and Mo for 0<y<0.1; and C is N, F, Br, and I for 0<z<0.1. Methods of preparation include sol gel, liquid flux, and co-precipitation processes.
    Type: Grant
    Filed: February 18, 2005
    Date of Patent: July 15, 2008
    Assignee: Intematix Corporation
    Inventors: Yi-Qun Li, Shifan Cheng, Ning Wang, Yi Dong, Xiao-Dong Sun
  • Patent number: 7340147
    Abstract: The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layer 1 and a core 2 that is formed on the under-clad layer 1 and has a higher refractive index than that of the under-clad layer 1 is shown. For example, KTN (KTa1-xNbxO3) is used as the core 2, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controllability widens the degree of freedom in the design of optical waveguide devices.
    Type: Grant
    Filed: May 24, 2006
    Date of Patent: March 4, 2008
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tadayuki Imai, Kazuo Fujiura, Makoto Shimokozono, Seiji Toyoda, Masahiro Sasaura, Tohru Matsuura
  • Publication number: 20070251445
    Abstract: Embodiments of an apparatus and methods for forming a tantalum containing film using plasma enhanced atomic layer deposition are generally described herein. Other embodiments may be described and claimed.
    Type: Application
    Filed: May 7, 2007
    Publication date: November 1, 2007
    Applicant: Tokyo Electron Limited
    Inventor: Tadahiro Ishizaka
  • Patent number: 7258740
    Abstract: The present invention relates to an apparatus for making a source material into a crystal fiber having different regions of polarization inversion. The apparatus of the present invention is similar to a laser-heated pedestal growth (LHPG) apparatus, characterized in that a first electric field generating device and a second electric field generating device are included. The first electric field generating device is used for providing a first external electric field which is used for poling the crystal fiber and inducing micro-swing of the crystal fiber. The second electric field generating device is disposed on a predetermined position above the first electric field generating device for providing a second external electric field to control and maintain the amplitude of the micro-swing. Whereby, the growth condition of the crystal fiber can be controlled precisely, and a uniformly and regularly periodic polarization inversion structure is fabricated.
    Type: Grant
    Filed: April 14, 2005
    Date of Patent: August 21, 2007
    Assignee: National Sun Yat-Sen University
    Inventors: Sheng-Lung Huang, Hsiao-Wen Lee, Chia-Chang Kuo, Sheng Bang Huang, Tsai-Shuan Chou, Li-Min Lee
  • Patent number: 7177514
    Abstract: The invention provides an optical waveguide material whose refractive index can be tailored without changing the ratio of Ta and Nb. An optical waveguide of this invention comprising an under-clad layer 1 and a core 2 that is formed on the under-clad layer 1 and has a higher refractive index than that of the under-clad layer 1 is shown. For example, KTN (KTa1?xNbxO3) is used as the core 2, and a material that is obtained by substituting at least one element selected from the group consisting of Zr, Hf, and Sn for a portion of one element of the constituent elements of KTN and has the same perovskite type crystal structure as KTN is used as the clad. The refractive index of KTN can be reduced considerably, and this controllability widens the degree of freedom in the design of optical waveguide devices.
    Type: Grant
    Filed: July 16, 2004
    Date of Patent: February 13, 2007
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Tadayuki Imai, Kazuo Fujiura, Makoto Shimokozono, Seiji Toyoda, Masahiro Sasaura, Tohru Matsuura
  • Patent number: 7090785
    Abstract: A perovskite compound of the formula, (Na1/2Bi1/2)1-xMx(Ti1-yM?y)O3±z, where M is one or more of Ca, Sr, Ba, Pb, Y, La, Pr, Nd, Sm, Eu, Gd, Th, Dy, Ho, Er, Tm, Yb and Lu; and M? is one or more of Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta, W, Cr, Mn, Fe, Co and Ni, and 0.01<x<0.3, and 0.01<y<0.3, and z<0.1 functions as an electromechanically active material. The material may possess electrostrictive or piezoelectric characteristics.
    Type: Grant
    Filed: August 5, 2003
    Date of Patent: August 15, 2006
    Assignee: Massachusetts Institute of Technology
    Inventors: Yet-Ming Chiang, Sossity A. Sheets, Gregory W. Farrey, Nesbitt W. Hagood, IV, Andrey Soukhojak, Haifeng Wang
  • Patent number: 7011705
    Abstract: A non-linear optical crystal of a compound having the general formula DxM1?xTOZO4, including isomorphs thereof, where: D is a dopant which comprises one or both of Rb and Cs; M is selected from one or both of K and Ag; T comprises one or more of Ti, Sn and Ge, optionally together with one or both of Nb and Ta; Z is selected from one or both of P and As, optionally together with one or both of Ge and Si; and 0<x?0.1.
    Type: Grant
    Filed: July 17, 2001
    Date of Patent: March 14, 2006
    Assignee: The University of Warwick
    Inventors: Pamela Anne Thomas, Keith Beveridge Hutton, Roger Charles Chavannes Ward
  • Patent number: 6996321
    Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.
    Type: Grant
    Filed: August 3, 2004
    Date of Patent: February 7, 2006
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masahiro Sasaura, Kazuo Fujiura, Koji Enbutsu, Tadayuki Imai, Shogo Yagi, Takashi Kurihara, Makoto Abe, Seiji Toyoda, Eishi Kubota
  • Patent number: 6932867
    Abstract: A method is provided for growing thin oxide films on the surface of a substrate by alternatively reacting the surface of the substrate with a metal source material and an oxygen source material. The oxygen source material is preferably a metal alkoxide. The metal source material may be a metal halide, hydride, alkoxide, alkyl, a cyclopentadienyl compound, or a diketonate.
    Type: Grant
    Filed: July 10, 2003
    Date of Patent: August 23, 2005
    Assignee: ASM International, N.V.
    Inventors: Mikko Ritala, Antti Rahtu, Markku Leskela, Kaupo Kukli
  • Patent number: 6929693
    Abstract: The invention relates to a tetragonal single crystal (1, 11) of composition: Z(H,D)2MO4 where Z is an element or a group of elements, or a mixture of elements and/or of groups of elements chosen from the group K, N(H,D)4, Rb, Ce where M is an element chosen from the group P, As and where (H,D) is hydrogen and/or deuterium comprising an approximately parallelepipedal region of large dimensions, especially one in which the length of each of the edges of the faces, AC1, AC2, AC3, is greater than or equal to 200 mm, in particular greater than or equal to 500 mm, which crystal is obtained by crystal growth from solution, from an approximately parallelepipedal single-crystal seed (2, 22) whose edges of the faces have lengths of AG1, AG2, AG3.
    Type: Grant
    Filed: November 7, 2001
    Date of Patent: August 16, 2005
    Assignee: Saint-Gobain Cristaux & Detecteurs
    Inventor: Vitali Tatartchenko
  • Patent number: 6926771
    Abstract: A method for growing stoichiometric lithium niobate and lithium tantalate single crystals is provided. A crystal growing apparatus that includes a long crucible with a separation member therein is used. A solid feed material is quenched from a molten state, solidified in batches or sintered before charged in the long crucible to obtain substantially stoichiometric solids. The separation member divides the long crucible into a melting zone and a feeding zone located under the melting zone, and it could effectively prevent bubble formation in the growing crystal. The stoichiometry of the axial and radial composition can be well controlled, and the control of the diameter of the crystal body is easily achieved as well.
    Type: Grant
    Filed: August 27, 2002
    Date of Patent: August 9, 2005
    Assignee: National Taiwan University
    Inventor: Chung-Wen Lan
  • Patent number: 6893500
    Abstract: A method of constructing optical filters using alternating layers of materials with “low” and “high” indices of refraction and deposited with atomic layer control. The multilayered thin film filter uses, but is not limited to, alternating layers of single crystal, polycrystalline or amorphous materials grown with self-limiting epitaxial deposition processes well known to the semiconductor industry. The deposition process, such as atomic layer epitaxy (ALE), pulsed chemical beam epitaxy (PCB E), molecular layer epitaxy (MLE) or laser molecular beam epitaxy (laser MBE) can result in epitaxial layer by layer growth and thickness control to within one atomic layer. The alternating layers are made atomically smooth using a Chemical Reactive-Ion Surface Planarization (CRISP) process. Intrinsic stress is monitored using an in-situ cantilever based intrinsic stress optical monitor and adjusted during filter fabrication by deposition parameter modification.
    Type: Grant
    Filed: May 24, 2001
    Date of Patent: May 17, 2005
    Assignee: Atomic Telecom
    Inventors: Gerald T. Mearini, Laszlo Takacs
  • Patent number: 6872251
    Abstract: A method for manufacturing single crystal ceramic powder is provided. The method includes a powder supply step for supplying powder consisting essentially of ceramic ingredients to a heat treatment area with a carrier gas, a heat treatment step for heating the powder supplied to the heat treatment area at temperatures required for single-crystallization of the powder to form a product, and a cooling step for cooling the product obtained in the heat treatment step to form single crystal ceramic powder. The method provides single crystal ceramic powder consisting of particles with a very small particle size and a sphericity being 0.9 or higher.
    Type: Grant
    Filed: May 29, 2002
    Date of Patent: March 29, 2005
    Assignee: TDK Corporation
    Inventors: Minoru Takaya, Yoshiaki Akachi, Hiroyuki Uematsu, Hisashi Kobuke
  • Patent number: 6792189
    Abstract: An optical waveguide capable of having various characteristics and a method of manufacture thereof as well as a method of manufacturing a crystal film are provided. An optical functional material KTaxNb1-xO3 is used as an optical waveguide. The input optical signal is transmitted to the KTaxNb1-xO3 film. The KTaxNb1-xO3 film undergoes changes in optical property when an external voltage signal is applied to the electrode. Therefore, as it passes through the KTaxNb1-xO3 film, the input optical signal is modulated by the characteristic change. The modulated optical signal is taken out as an output optical signal.
    Type: Grant
    Filed: May 13, 2002
    Date of Patent: September 14, 2004
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Masahiro Sasaura, Kazuo Fujiura, Koji Enbutsu, Tadayuki Imai, Shogo Yagi, Takashi Kurihara, Makoto Abe, Seiji Toyoda, Eishi Kubota
  • Patent number: 6786967
    Abstract: A method for fabricating ion exchange waveguides, such as lithium niobate or lithium tantalate waveguides in optical modulators and other optical waveguide devices, utilizes pressurized annealing to further diffuse and limit exchange of the ions and includes ion exchanging the crystalline substrate with a source of ions and annealing the substrate by pressurizing a gas atmosphere containing the lithium niobate or lithium tantalate substrate above normal atmospheric pressure, heating the substrate to a temperature ranging from about 150 degrees Celsius to about 1000 degrees Celsius, maintaining pressure and temperature to effect greater ion diffusion and limit exchange, and cooling the structure to an ambient temperature at an appropriate ramp down rate. In another aspect of the invention a powder of the same chemical composition as the crystalline substrate is introduced into the anneal process chamber to limit the crystalline substrate from outgassing alkaline earth metal oxide during the anneal period.
    Type: Grant
    Filed: October 15, 1999
    Date of Patent: September 7, 2004
    Assignee: California Institute of Technology
    Inventor: Lee J. Burrows
  • Patent number: 6770132
    Abstract: In one aspect of the invention, a method for pressurized annealing of lithium niobate or lithium tantalate structures, such as optical modulators and optical wave guides, comprises pressurizing an oxygen atmosphere containing a lithium niobate or lithium tantalate structure above normal atmospheric pressure, heating the structure to a temperature ranging from about 150 degrees Celsius to about 1000 degrees Celsius, maintaining pressure and temperature to effect ion exchange or to relieve stress, and cooling the structure to an ambient temperature at an appropriate ramp down rate.
    Type: Grant
    Filed: May 11, 1999
    Date of Patent: August 3, 2004
    Assignee: California Institute of Technology
    Inventor: Lee J. Burrows
  • Patent number: 6673330
    Abstract: A single crystal of lithium niobate or lithium tantalate may be grown from a melt of a composition having a molar excess of Li compared to a melt having the stoichiometric amount of lithium, and having a molar fraction of Li2O/(Nb2O5+Li2O) or Li2O/(Ta2O5+Li2O) within a range of at least 0.490 and less than 0.500. The single crystal also has at least one element selected from the group consisting of Mg, Zn, Sc and In, in an amount of from 0.1 to 3.0 mol % based on the total amount of the elements, Nb and Li, or the total amount of the elements, Ta and Li.
    Type: Grant
    Filed: March 9, 2000
    Date of Patent: January 6, 2004
    Assignee: National Institute for Research in Inorganic Materials
    Inventors: Kenji Kitamura, Yasunori Furukawa, Shunji Takekawa, Shigeyuki Kimura
  • Patent number: 6632279
    Abstract: A method is provided for growing thin oxide films on the surface of a substrate by alternatively reacting the surface of the substrate with a metal source material and an oxygen source material. The oxygen source material is preferably a metal alkoxide. The metal source material may be a metal halide, hydride, alkoxide, alkyl, a cyclopentadienyl compound, or a diketonate.
    Type: Grant
    Filed: October 13, 2000
    Date of Patent: October 14, 2003
    Assignee: ASM Microchemistry, Oy
    Inventors: Mikko Ritala, Antti Rahtu, Markku Leskela, Kaupo Kukli
  • Patent number: 6605227
    Abstract: A method of manufacturing a ridge-shaped 3-dimensional waveguide, has the steps of: forming a crystal film made of a second ferroelectric oxide non-linear crystal having a refractive index higher than that of a substrate made of a first ferroelectric oxide non-linear crystal on the substrate; forming a metal film on the crystal film; forming a mask by etching the metal film; and forming a ridge portion by selectively removing the crystal film through the mask by a dry etching method.
    Type: Grant
    Filed: October 25, 1999
    Date of Patent: August 12, 2003
    Assignee: Pioneer Corporation
    Inventors: Ayako Yoshida, Atsushi Onoe, Kiyofumi Chikuma
  • Patent number: 6597492
    Abstract: A method of fabricating an invertedly poled domain structure having alternating sections of opposite electric polarities, from a ferroelectric crystal wafer (1) having two opposite polar surfaces, comprises patterning at least one of the two polar surfaces of the wafer to comprise a plurality of alternating discrete regions, of which first regions are adapted for and second regions are protected from the direct application thereto of an electric contact; applying to both polar surfaces of the wafer electrically conducting electrodes (10 and 11) so that the first regions are in direct contact with the electrodes and the second regions are protected from such a contact; and applying to the electrodes an electrical field (20) of the intensity E. The electrical field is applied to the wafer at a working temperature by heater/cooler (15).
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: July 22, 2003
    Assignees: The State of Israel Atomic Energy Commission Soreq Nuclear Research Center, Ramot University Authority for Applied Research & Industrial Development Ltd.
    Inventors: Gil Rosenman, Alexander Skliar, Moshe Oron, David Eger, Mordechai Katz
  • Patent number: 6565648
    Abstract: An electrolyte solution is used as a liquid electrode. The liquid electrode, as one electrode, is faced with a domain to be subjected to polarization inversion on one side surface of a substrate made of a ferro-electric crystal, and an electrolyte solution, as the other liquid electrode, is faced with the other surface of the substrate to allow an electric field to act at least on the domain to be subjected to polarization inversion. A polarization inverting voltage is applied onto the substrate via the both liquid electrodes at a temperature of 45° C. or above, thereby to invert the direction of polarization. By this method, a periodically-poled structure of an Mg doped LiNbO3 crystal having a high quality can be formed.
    Type: Grant
    Filed: October 2, 2000
    Date of Patent: May 20, 2003
    Assignee: Mitsubishi Cable Industries, Ltd.
    Inventors: Masaru Nakamura, Hirokazu Taniguchi, Hirotaka Ito
  • Publication number: 20030084837
    Abstract: A nonlinear crystal has increased spectral acceptance. The nonlinear crystal includes a plurality of domains. The domains are arranged serially across the nonlinear crystal. The domains have alternating polarity. The poling periods of the domains are varied across the nonlinear crystal so as to provide nonuniform chirping of phase matching of focused optical signals propagated through the nonlinear crystal.
    Type: Application
    Filed: November 6, 2001
    Publication date: May 8, 2003
    Inventors: Gregory Steven Lee, Roger Lee Jungerman
  • Patent number: 6447606
    Abstract: A method for producing a single-crystalline film made of a single crystal of lithium potassium niobate-lithium potassium tantalate solid solution or a single crystal of lithium potassium niobate, including the steps of preparing a target made of a material for the single-crystalline film, preparing a foundation made of a single crystal of lithium potassium niobate-lithium potassium tantalate solid solution or a single crystal of lithium potassium niobate, irradiating the target to gasify molecules constituting the target by dissociation and evaporation thereof, and epitaxially growing the single-crystalline film on the foundation.
    Type: Grant
    Filed: May 26, 1999
    Date of Patent: September 10, 2002
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Takashi Yoshino
  • Patent number: 6440210
    Abstract: A method for producing self-polarized ferroelectric layers, in particular PZT layers, with a rhombohedral crystal structure includes providing a substrate and heating it to a temperature T1. Afterward the layer with a rhombohedral crystal structure is applied to the substrate by means of a sputtering method. This layer includes a Zr-deficient layer with a Curie temperature TC1 and a Zr-abundant layer with a Curie temperature TC2 wherein TC2<TC1<T1. After the ending of the application process, the heating of the substrate is also discontinued so that the substrate cools. As a result of the cooling the Zr-deficient layer and then the Zr-abundant layer reach their Curie temperature, and change into the ferroelectric phase and become self-polarized in the process. The polarization already present in the Zr-deficient layer induces the polarization in the Zr-abundant layer, with the result that both layers are self-polarized after the cooling process.
    Type: Grant
    Filed: March 16, 2001
    Date of Patent: August 27, 2002
    Assignee: Siemens Aktiengesellschaft
    Inventors: Rainer Bruchhaus, Dana Pitzer, Robert Primig, Matthias Schreiter
  • Patent number: 6402834
    Abstract: In a monocrystal producing device using a pulling-down method, a raw material melt 5m is continuously supplied into a crucible 2 to grow a crystal 18 by supplying a powdery raw material 5p onto a premelt plate 3 inside an electric furnace 10 with a powdery raw material supplying device 20 and melting the powdery raw material 5p on the premelt plate 3 to generate the raw material melt 5m, and causing this raw material melt 5m to drop out inside the crucible 2. A dry air is introduced into the powdery raw material 5p inside the powdery raw material tank 6 to prevent moisture of the raw material powder 5p. A transferring tube 9 for transferring the raw material 5m is cooled to prevent the filling in the transferring tube 9 based on melting of the powdery raw material 5p. This makes it possible to produce a monocrystal having a stable chemical composition, a large diameter, and a long size at a low price.
    Type: Grant
    Filed: January 31, 2000
    Date of Patent: June 11, 2002
    Assignees: Toyo Communication Equipment Co., Ltd.
    Inventors: Kunihiko Nagai, Kohei Kodaira, Hiroyuki Tanaka, Hideki Sakamoto
  • Patent number: 6149975
    Abstract: When a potassium-containing substance is formed in to a film using an organic potassium complex as a potassium source by the CVD method, it is prevented that the film formation rate is changed with the lapse of time, and the potassium content in the film thus formed is changed.As a potassium source for vaporization used for depositing the potassium-containing substance on a substrate by the CVD method, a .beta.-diketone complex of potassium that has been melted by heating to a temperature higher than its melting point and then cooled to be solidified is used.
    Type: Grant
    Filed: March 10, 1999
    Date of Patent: November 21, 2000
    Assignees: Dowa Mining Co., Ltd., Pioneer Electronic Corporation
    Inventors: Yuzo Tasaki, Mamoru Satoh, Atsushi Onoe, Ayako Yoshida, Kiyofumi Chikuma
  • Patent number: 6074477
    Abstract: A process is disclosed for producing an integrated composite oxide single crystal body composed of a core portion made of an oxide single crystal and a clad portion integrated with the core portion and made of another oxide single crystal having a composition different from that of the oxide single crystal constituting the core portion, the process comprising the steps of: (1) preparing a first melt in a first crucible by melting a first material for a first oxide single crystal to constitute the core portion inside the first crucible, (2) preparing a second melt inside a second crucible by melting a second material for a second oxide single crystal to constitute the clad portion inside the second crucible, (3) contacting a seed crystal to the first and second melts, (4) pulling down the first melt through a pull-out opening of the first crucible, (5) pulling down the second melt through a pull-out opening of the second crucible and contacting the pulled-down second melt with a pulled-down portion of the firs
    Type: Grant
    Filed: March 12, 1998
    Date of Patent: June 13, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Tsuguo Fukuda, Kiyoshi Shimamura, Tatsuo Kawaguchi
  • Patent number: 6051062
    Abstract: In producing an optical single crystal epitaxial film from a melt containing a transition metal on a single crystal substrate by a liquid phase epitaxial method, this process contains the steps of: annealing the film at a predetermined temperature in an ozonic atmosphere; and temperature-increasing and -decreasing to and from the predetermined temperature, wherein at least one of temperature-increasing and -decreasing steps, the film is exposed to a substantially ozone-free atmosphere.
    Type: Grant
    Filed: November 12, 1997
    Date of Patent: April 18, 2000
    Assignee: NGK Insulators, Ltd.
    Inventors: Tatsuo Kawaguchi, Minoru Imaeda
  • Patent number: 5919304
    Abstract: When producing an oxide-series single crystal by continuously pulling downwardly by .mu. pulling down method, the composition of the single crystal can properly and quickly controlled to continuously produce the single crystal of a constant composition by changing the pulling rate of the single crystal. Preferably, the pulling rate is 20-300 mm/hr, and the pulling rate is decreased with the proceeding of growing of the single crystal.
    Type: Grant
    Filed: August 23, 1996
    Date of Patent: July 6, 1999
    Assignee: NGK Insulators, Ltd.
    Inventors: Minoru Imaeda, Katsuhiro Imai, Tsuguo Fukuda
  • Patent number: 5904771
    Abstract: A method of subliming material is provided for use in a CVD film preparation method wherein a CVD precursor is sublimed from its solid state by heating to a temperature not exceeding its melting point, thereby producing a vapor of the precursor, and the vapor of the precursor is transported to a reactor. The method of subliming material comprises the steps of forming the solid-state compound into a film, covering a back surface of the film with a non-reactive support and exposing a front surface of the film to an atmosphere as a sublimation surface. The method maintains the exposed surface area of the solid compound constant during processing.
    Type: Grant
    Filed: April 3, 1997
    Date of Patent: May 18, 1999
    Assignees: Dowa Mining Co., Ltd., Pioneer Electric Corporation
    Inventors: Yuzo Tasaki, Mamoru Sato, Shuji Yoshizawa, Atsushi Onoe, Kiyofumi Chikuma, Ayako Yoshida
  • Patent number: 5904912
    Abstract: An iron-doped lithium niobate single crystal having a molar fraction of Li.sub.2 O/(Nb.sub.2 O.sub.5 +Li.sub.2 O) of from 0.495 to 0.50 which is closer to the stoichiometrical composition than a usual congruent composition, and a high diffraction efficiency by a two light wave mixture.
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: May 18, 1999
    Assignee: National Institute for Research in Inorganic Materials
    Inventors: Kenji Kitamura, Yasunori Furukawa, Nobuo Ii, Shigeyuki Kimura
  • Patent number: 5882400
    Abstract: The invention concerns a method of producing a surface layer structure by doping a matrix with metal ions. The aim of the invention is to provide a method of this kind in which the depth distribution of the metal ions in the substrate can be regulated, thus optimumizing the doping without incurring any of the disadvantages inherent in the prior art methods. This is achieved by first depositing matrix material on a suitable substrate by laser ablation in an atmosphere of oxygen, thus forming a on surface of the substrate a first layer a matrix material. Dopant is then deposited on the surface of the first layer, followed by more matrix material. The result is a uniform doping of the deposited matrix at a defined depth in the surface layer structure.
    Type: Grant
    Filed: May 10, 1996
    Date of Patent: March 16, 1999
    Assignee: Forschungszentrum Julich GmbH
    Inventors: Stefanie Bauer, Martin Fleuster, Willi Zander, Jurgen Schubert, Christoph Buchal
  • Patent number: 5766340
    Abstract: A method for poling a ferroelectric crystal includes heating the crystal to a temperature above its Curie temperature and applying a first selected voltage to the electrodes to apply an electric field to the crystal. The temperature of the crystal is then reduced to a temperature below the Curie temperature of the crystal, and a second electric field having polarity opposite to the polarity of the first electric field is applied to the crystal. Application of the second electric field reduces nonuniformity in ion concentration across the crystal.
    Type: Grant
    Filed: March 28, 1997
    Date of Patent: June 16, 1998
    Assignee: Litton Systems, Inc.
    Inventor: Christine E. Geosling
  • Patent number: 5759265
    Abstract: A buffer layer having crystal orientation In a (111) face is formed on a semiconductor single-crystal (100) substrate and a ferroelectric thin film having crystal orientation in a (111) or (0001) face is then formed over the buffer layer. The buffer layer is preferably formed of MgO at a temperature ranging from 20.degree. to 600.degree. C. and at a rate ranging from 0.5 to 50 .ANG./sec. The thus formed ferroelectric thin film has its axes of polarization aligned in one direction. Using the oriented ferroelectric thin-film device, highly functional nonvolatile memories, capacitors or optical modulators can be fabricated on semiconductor substrates.
    Type: Grant
    Filed: May 3, 1995
    Date of Patent: June 2, 1998
    Assignee: Fuji Xerox Co., Ltd.
    Inventors: Keiichi Nashimoto, Atsushi Masuda