Barium Titanate Patents (Class 501/137)
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Patent number: 6616794Abstract: A method for producing integral capacitance components for inclusion within printed circuit boards. Hydrothermally prepared nanopowders permit the fabrication of a very thin dielectric layers that offer increased dielectric constants and are readily penetrated by microvias. Disclosed is a method of preparing a slurry or suspension of a hydrothermally prepared nanopowder and solvent. A suitable bonding material, such as a polymer is mixed with the nanopowder slurry, to generate a composite mixture which is formed into a dielectric layer. The dielectric layer may be placed upon a conductive layer prior to curing, or conductive layers may be applied upon a cured dielectric layer, either by lamination or by metallization processes, such as vapor deposition or sputtering.Type: GrantFiled: May 4, 1999Date of Patent: September 9, 2003Assignee: TPL, Inc.Inventors: William F. Hartman, Kirk M. Slenes, Kristen J. Law
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Patent number: 6613706Abstract: A dielectric ceramic composition includes sintered ceramic grains having a core-shell structure, wherein 50%˜80% of the grains have a domain width of twin smaller than 20 nm; not greater than 30% of the grains have a domain width of twin in the range from 20 nm to 50 nm; not smaller than 10% of the grains have a domain width of twin greater than 50 nm or have no twin.Type: GrantFiled: May 24, 2002Date of Patent: September 2, 2003Assignee: Taiyo Yuden Co., Ltd.Inventors: Tomoya Hagiwara, Koichiro Morita, Youichi Mizuno
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Publication number: 20030158032Abstract: A dielectric ceramic composition comprising a main component of BaTiO3, a first subcomponent including at least one compound selected from MgO, CaO, BaO, SrO and Cr2O3, a second subcomponent of (Ba, Ca)xSiO2+x (where, x=0.8 to 1.2), a third subcomponent including at least one compound selected from V2O5, MoO3, and WO3, and a fourth subcomponent including an oxide of R1 (where R1 is at least one element selected from Sc, Er, Tm, Yb, and Lu), a fifth subcomponent including an oxide of R2 (where R2 is at-least one element-selected from Y, Dy, Ho, Tb, Gb and Eu), wherein the ratios of the subcomponents to 100 moles of the main component of BaTiO3 are first subcomponent of 0.1 to 3 moles, second subcomponent of 2 to 10 moles, third subcomponent of 0.01 to 0.5 mole, fourth subcomponent of 0.5 to 7 moles, and fifth subcomponent of 2 to 9 moles (where the number of moles of the fourth and fifth subcomponents are respectively the ratio of R1 and R2 alone).Type: ApplicationFiled: February 20, 2003Publication date: August 21, 2003Applicant: TDK CORPORATIONInventors: Yoshinori Fujikawa, Yoshihiro Terada, Shigeki Sato
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Publication number: 20030148873Abstract: A uniform suspension of ceramic powder and method for making the same. The suspension is prepared by mixing finely divided ceramic powder in an aqueous carrier fluid, combining with a dispersing agent, and alternatively, an organic binder when forming a slip. The ceramic powder has an average particle size of about 0.5 micron or less and is present in the suspension in a loading of up to 30% by volume of the total solids in suspension. A passivating agent is present in the carrier fluid in an amount of 0.5 to 5% by weight of the ceramic powder present for suspension and slip respectively. After the addition of a dispersant, the suspension has a Bingham yield point of less than 230 dynes/cm2 and an apparent viscosity of less than 3000 cps. A green layer produced from the slip exhibits a pore size of less than 0.5 micron.Type: ApplicationFiled: November 21, 2002Publication date: August 7, 2003Inventors: James H. Adair, Stephen A. Costantino
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Publication number: 20030146406Abstract: A piezoelectric/electrostrictive material is made of a BaTiO3-based porcelain composed mainly of BaTiO3, and a strain (S4000) of transversal direction is 650×10−6 or more in an electric field of 4,000 V/mm. This porcelain has a Curie temperature of 110 to 130° C., and its crystal phase at ambient temperature consists essentially of tetragonal and cubic phases. The piezoelectric/electrostrictive material being composed of this porcelain is superior in strain to conventional products, and can be suitably used in an actuator or a sensor.Type: ApplicationFiled: December 19, 2002Publication date: August 7, 2003Applicant: NGK Insulators, Ltd.Inventors: Hirofumi Yamaguchi, Takaaki Koizumi
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Publication number: 20030139281Abstract: The invention relates to a ceramic and processes for preparation of this ceramic, the said ceramic being based on cesium with a hollandite structure with the formula AxBy(C1z1,C2z2)DtO16, in which:Type: ApplicationFiled: December 4, 2002Publication date: July 24, 2003Inventors: Gilles Leturcq, Florence Bart, Adeline Comte
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Publication number: 20030134738Abstract: Provided is a piezoelectric ceramic capable of improving its piezoelectric properties. The piezoelectric ceramic comprises a rhombohedral perovskite structure compound such as (Na0.5Bi0.5)TiO3, a tetragonal perovskite structure compound such as BaTiO3 and (K0.5Bi0.5)TiO3 and an orthorhombic perovskite structure compound such as NaNbO3, KNbO3 and CaTiO3, or the rhombohedral perovskite structure compound, the tetragonal perovskite structure compound and a cubic perovskite structure compound such as SrTiO3. Three kinds of perovskite structure compounds having different crystal structures are comprised, so that the piezoelectric properties can be improved. The three kinds of compounds may perfectly form a solid solution or not.Type: ApplicationFiled: July 16, 2002Publication date: July 17, 2003Inventors: Masahito Furukawa, Kenji Horino, Shogo Murosawa, Yoshiko Gokita
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Patent number: 6585951Abstract: Methods for manufacturing a powder of a dielectric compound include mixing particle components that are combinable to form the dielectric compound with matrix components. The mixture is melted, and the molten mixture is quenched to produce a solid material. The dielectric power is extracted from the solid material. A molar ratio of particle components to matrix components can be selected so that the solid material produced by quenching is amorphous. Particle components can be selected to produce Ba1−xSrxTiO3 powder, wherein 0≦x≦1. Matrix components consist essentially of Na2O·2B2O3 and Na2O·SiO2·9H2O or can be selected from a group consisting of zinc oxide, zinc carbonate, and zinc hydroxide.Type: GrantFiled: October 30, 2000Date of Patent: July 1, 2003Assignee: Idaho Research Foundation, Inc.Inventors: Yang-Ki Hong, Mun-Hyoun Park
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Publication number: 20030119656Abstract: The production of low-loss, tunable composite ceramic materials with improved breakdown strengths is disclosed. The composite materials comprise ferroelectric perovskites such as barium strontium titanate or other ferroelectric perovskites combined with other phases such as low-loss silicate materials and/or other low-loss oxides. The composite materials are produced in sheet or tape form by methods such as tape casting. The composite tapes exhibit favorable tunability, low loss and tailorable dielectric properties, and can be used in various microwave devices.Type: ApplicationFiled: November 22, 2002Publication date: June 26, 2003Applicant: Paratek Microwave, Inc.Inventors: Luna H. Chiu, Xubai Zhang, Louise C. Sengupta
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Publication number: 20030114295Abstract: A piezoelectric/electrostrictive material is made of a BaTiO3-based porcelain composed mainly of BaTiO3 and containing CuO and Nb2O5. 85% or more of the crystal grains constituting the porcelain are grains having particle diameters of 10 &mgr;m or less and the maximum particle diameters of the grains are in a range of 5 to 25 &mgr;m. This BaTiO3-based piezoelectric/electrostrictive material is superior in piezoelectric/electrostrictive properties to conventional products and can be suitably used in an actuator or a sensor.Type: ApplicationFiled: May 20, 2002Publication date: June 19, 2003Applicant: NGK Insulators, Ltd.Inventors: Hirofumi Yamaguchi, Takaaki Koizumi
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Patent number: 6579467Abstract: The invention comprises ferroelectric vapor deposition targets and to methods of making ferroelectric vapor deposition targets. In one implementation, a ferroelectric physical vapor deposition target has a predominate grain size of less than or equal to 1.0 micron, and has a density of at least 95% of maximum theoretical density. In one implementation, a method of making a ferroelectric physical vapor deposition target includes positioning a prereacted ferroelectric powder within a hot press cavity. The prereacted ferroelectric powder predominately includes individual prereacted ferroelectric particles having a maximum straight linear dimension of less than or equal to about 100 nanometers. The prereacted ferroelectric powder is hot pressed within the cavity into a physical vapor deposition target of desired shape having a density of at least about 95% of maximum theoretical density and a predominate maximum grain size which is less than or equal to 1.0 micron.Type: GrantFiled: May 8, 2002Date of Patent: June 17, 2003Assignee: Honeywell International Inc.Inventors: Jianxing Li, Tim Scott, Tamara White
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Patent number: 6579468Abstract: A piezoelectric ceramic composition contains a compound containing Na, Li, Nb and O, and having a perovskite structure, as a main component. The main component has a crystal phase in a semi-stable state at room temperature, such crystal phase originally not being stable at room temperature but being stable at a higher temperature.Type: GrantFiled: May 29, 2002Date of Patent: June 17, 2003Assignee: Murata Manufacturing Co. Ltd.Inventors: Masahiko Kimura, Akira Ando, Tomoyuki Ogawa
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Publication number: 20030107455Abstract: An integrated ceramic module is formed of a first ceramic dielectric layer containing a glass as a sintering agent and having a high dielectric constant and high Q value, formed with an electronic component, and a second ceramic dielectric layer containing a glass as a sintering agent and having a low dielectric constant and a high Q value, formed with a signal transmission line.Type: ApplicationFiled: October 22, 2002Publication date: June 12, 2003Inventors: Yoshihiko Imanaka, Masatoshi Takenouchi
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Publication number: 20030109375Abstract: The invention relates to a ceramic mass (1) consisting of one ceramic material (2) and at least one other kind of ceramic material (3) different therefrom. Glass material (4) is arranged between the ceramic materials. The glass material reduces the sintering temperature of the ceramic mass and prevents the various ceramic materials from forming a mixed crystal when the ceramic mass is sintered. The ceramic mass is suitable for use in LTCC technology for the production of capacitors whose permittivity is dependent upon a specific temperature range.Type: ApplicationFiled: September 13, 2002Publication date: June 12, 2003Inventors: Silvia Gohlke, Ruth Manner, Gabriele Preu, Wolfram Wersing
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Patent number: 6572793Abstract: A method of producing an electronic device including a dielectric layer includes a dielectric ceramic composition containing a main component expressed by a formula of {(Sr1−xCax)O}m.(Ti1−yZry)O2, wherein x fulfills 0≦x≦1.00 and y fulfills 0≦y≦0.20, and producing said dielectric ceramic composition by using a material expressed by a formula of {(Sr1−xCax)O}m′.(Ti1−yZry)O2 wherein the mole ratio m′ fulfills m′<m. It is possible to produce an electronic device, such as a chip capacitor, having excellent resistance to reducing during firing and excellent capacity-temperature characteristics after firing, wherein the insulation resistance is hard to be deteriorated particularly when made to be a thin layer and defect rate of the initial insulation resistance is low.Type: GrantFiled: March 19, 2001Date of Patent: June 3, 2003Assignee: TDK CorporationInventors: Takashi Fukui, Yasuo Watanabe, Mikio Takahashi, Akira Sato
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Publication number: 20030100438Abstract: The present invention discloses low-cost ceramic powders prepared by the conventional ceramic processing with ceramic raw materials comprising carbonates, oxides and/or hydroxides of barium (Ba), titanium (Ti), magnesium (Mg) and optionally strontium (Sr), lanthanum (La) and niobium (Nb), and lead titanate (PbTiO3) and/or lead oxide (PbO). The present invention also discloses a ceramic material obtained by the ceramic powder through densification and reduction-reoxidation, which has a dielectric constant of about 20,000 to about 55,000, a dielectric loss tangent (tan &dgr;) of about 0.05 to about 0.25, a low capacitance change with temperature (low TCC) of about −15% to about 10% at a temperature range of −55° C. to 150° C., a resistivity of about 106 &OHgr;·cm to about 109 &OHgr;·cm, and a small grain size of about 0.5 to about 3.5 &mgr;m.Type: ApplicationFiled: October 9, 2001Publication date: May 29, 2003Inventors: Dong-Hau Kuo, Chih-Hung Wang
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Patent number: 6569795Abstract: A high-frequency dielectric ceramic compact is provided which has a relative dielectric constant (∈r) of about 20 or less and a Q value of about 20,000 or more at 1 GHz, in which the temperature coefficient (&tgr;f) can be optionally controlled at about 0 (ppm/° C.). When the compact of the dielectric ceramic compact is represented by the formula aBaO.bMeO.cSbO3/2, 0.476≦a≦0.513, 0.160≦b≦0.175, and 0.324≦c≦0.350. In addition, when the compact of the dielectric ceramic compact is represented by the formula dBaO.eMeO.fSbO3/2.gTiO2, 0.476≦d≦0.513, 0.100≦e≦0.175, 0.200≦f≦0.349, and 0<g≦0.200.Type: GrantFiled: June 28, 2001Date of Patent: May 27, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Mizuki Kono, Tsutomu Tatekawa, Hitoshi Takagi
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Patent number: 6568219Abstract: The specification describes ceram-glass compositions useful for electro-optic devices. The compositions have active ferroelectric ingredients in a tellurium oxide host. Proper processing of the ceram-glass produces highly transparent material with desirable ferroelectric properties. The ceram-glass materials can be used for electro-optic devices in both bulk and thin film applications.Type: GrantFiled: July 31, 2000Date of Patent: May 27, 2003Assignee: Lucent Technologies Inc.Inventors: Alastair Malcolm Glass, Benjamin Irvin Greene, Nonna Kopylov, Ahmet Refik Kortan
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Publication number: 20030085375Abstract: The subject invention includes a composite material comprising a ferroelectric material and a ferromagnetic material having a loss factor (tan &dgr;) for the composite material which includes a dielectric loss factor of the ferroelectric material and a magnetic loss factor of the ferromagnetic material. The composite material achieves the loss factor of from 0 to about 1.0 for a predetermined frequency range greater than 1 MHz. The ferroelectric material has a dielectric loss factor of from 0 to about 0.5 and the ferromagnetic material has a magnetic loss factor of from 0 to about 0.5 for the predetermined frequency range. The ferroelectric material is present in an amount from 10 to 90 parts by volume based on 100 parts by volume of the composite material and the ferromagnetic material is present in an amount from 10 to 90 parts by volume based upon 100 parts by volume of the composite material such that the amount of the ferroelectric material and the ferromagnetic material equals 100 parts by volume.Type: ApplicationFiled: November 1, 2001Publication date: May 8, 2003Applicant: Delphi Technologies Inc.Inventors: Norman W. Schubring, Joseph V. Mantese, Adolph L. Micheli
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Patent number: 6559083Abstract: The present invention provides a dielectric ceramic composition comprising a base material represented by the general formula: (x) Al2O3+(y) TiO2, where x and y are percentages of the total weight of the base material, with x being in the range of about 60 to about 96 and y being in the range of about 4 to about 40. Also provided is a first additive material comprising Nb2O5 and a second additive material comprising BaZrO3. In another embodiment the present invention provides a sintered dielectric ceramic composition comprising a base material represented by the general formula: (x) Al2O3+(y) TiO2, where x and y are percentages of the total weight of the base material, with x being in the range of about 60 to about 96 and y being in the range of about 4 to about 40. Also provided is a first additive material comprising Nb2O5 and a second additive material comprising BaZrO3.Type: GrantFiled: April 17, 2001Date of Patent: May 6, 2003Assignee: CTS CorporationInventors: Jeffrey R. Jacquin, Randy E. Rose
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Patent number: 6558567Abstract: Provided is a piezoelectric ceramic compact useful as a material for a piezoelectric ceramic compact device or the like, having SrBi4Ti4O15 as a main component, containing no or a small amount of lead or lead compound, and exhibiting a Qmax improved to a level permitting practical use application. The piezoelectric ceramic compact includes a bismuth layer compound as a main component composed of Sr, Bi, Ti and oxygen, and when the molar ratio of Sr, Bi and Ti of the bismuth layer compound as the main component is a:b:c, the relations of 0.13≦a/c<0.25 and 3.5≦(2a+3b)/c≦3.75 are satisfied.Type: GrantFiled: May 18, 2001Date of Patent: May 6, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Masahiko Kimura, Takuya Sawada, Akira Ando
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Patent number: 6556423Abstract: A dielectric ceramic has a ceramic structure of crystal grains and grain boundaries between the crystal grains. The crystal grains are of a main component represented by the formula ABO3 and an additive containing a rare earth element wherein A is at least one of barium, calcium, and strontium, barium being an essential element, and B is at least one of titanium, zirconium, and hafnium, titanium being an essential element. The average rare earth element concentration in the interior of the crystal grains is about 50% or less the average rare earth element concentration at the grain boundaries. Furthermore, about 20% to 70% of the crystal grains have a rare earth element concentration in the center of the crystal grain of at least about {fraction (1/50)} the maximum rare earth element concentration in a region extending inward from the surface by a distance corresponding to about 5% of the diameter of the crystal grain.Type: GrantFiled: March 7, 2002Date of Patent: April 29, 2003Assignee: Murata Manufacturing Co. Ltd.Inventors: Hiroyasu Konaka, Tomoyuki Nakamura, Toshihiro Okamatsu, Harunobu Sano
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Patent number: 6551522Abstract: Piezoelectric ceramics include a bismuth layer compound containing MII, Bi, Ti, Ln and O, wherein MII represents at least one element selected from the group consisting of Sr, Ba and Ca, and Ln represents at least one element selected from the group consisting of lanthanoids. The piezoelectric ceramics include MIIBi4Ti4O15 typed crystals, and a mole ratio of Ln/(Ln+MII) is 0<Ln/(Ln+MII)<0.5. In the case where MII is Sr, a mole ratio of 4Bi/Ti is 4.000<4Bi/Ti≦4.030. Preferably, piezoelectric ceramics further include Y oxide.Type: GrantFiled: February 7, 2001Date of Patent: April 22, 2003Assignee: TDK CorporationInventors: Masakazu Hirose, Takeo Tsukada, Hitoshi Oka, Junji Terauchi
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Publication number: 20030073565Abstract: Tunable dielectric materials including an electronically tunable dielectric ceramic and a low loss glass additive are disclosed. The tunable dielectric may comprise a ferroelectric perskovite material such as barium strontium titanate. The glass additive may comprise boron, barium, calcium, lithium, manganese, silicon, zinc and/or aluminum-containing glasses having dielectric losses of less than 0.003 at 2 GHz. The materials may further include other additives such as non-tunable metal oxides and silicates. The low loss glass additive enables the materials to be sintered at relatively low temperatures while providing improved properties such as low microwave losses and high breakdown strengths.Type: ApplicationFiled: May 31, 2002Publication date: April 17, 2003Inventors: Marion E. Ellis, Steven Wesley Winn, Luna H. Chiu
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Patent number: 6548437Abstract: Provided are dielectric ceramics and an electronic component capable of enhancing the longevity of insulation resistance under load at high temperature, namely, the so-called lifetime of IR degradation. A dielectric layer comprises dielectric ceramics containing BaTiO3 that is a main component; a first auxiliary component containing at least one element in a group consisting of Mg, Ca, Ba, Sr and Cr; a second auxiliary component containing SiO2; a third auxiliary component containing at least one element in a group consisting of V, Mo and W; and a fourth auxiliary component containing at least one element in a group consisting of Er, Tm, Yb, Y, Dy and Ho. Preferably, the rate of existence of crystal particles having voids in the dielectric ceramics is 10% or lower in terms of the count rate, and an average crystal particle diameter is more than 0.1 &mgr;m and not more than 0.7 &mgr;m. Thus, the lifetime of IR degradation is improved.Type: GrantFiled: April 17, 2001Date of Patent: April 15, 2003Assignee: TDK CorporationInventors: Shigeki Sato, Yoshihiro Terada, Yoshinori Fujikawa
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Patent number: 6544916Abstract: A method of manufacturing a dielectric ceramic composition comprising at least BaTiO3 as a main component, a second subcomponent having SiO2 as a main component and at least one type selected from MO (note that M is at least one type of element selected from Ba, Ca, Sr and Mg), Li2O and B2O3 and other subcomponents, comprising the steps of mixing in the main component at least part of other subcomponents except for the second subcomponent to prepare a pre-calcination powder, calcining said pre-calcination powder to prepare a calcined powder, and mixing at least said second subcomponent in said calcined powder to obtain a dielectric ceramic composition having ratios of the subcomponents to BaTiO3 as the main component of predetermined molar ratios.Type: GrantFiled: June 4, 2001Date of Patent: April 8, 2003Assignee: TDK CorporationInventors: Shigeki Sato, Yoshihiro Terada, Yoshinori Fujikawa
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Patent number: 6534429Abstract: A multi-component material is represented by the general formula (I): Ba(1−y−y)PbyMxTiO3 (I) in which: M is Sr or Cd; x is the decimal fraction molar concentration of MTiO3, where x has a value equal to or greater than about 0.20 and less than or equal to about 0.75; and y is the decimal fraction molar concentration of PbTiO3, where y has a value greater than zero and less than or equal to about 0.40, and x+y is less than 1.0. In addition, a method of graphically estimating the composition of the multi-component material represented by the general formula (I) is disclosed herein. In a preferred embodiment, x has a value between about 0.28 and 0.66, and y has value greater than zero and less than or equal to about 0.34, while said material has a Curie point temperature of about 25° C. or room temperature. These room temperature Curie point materials are useful in uncooled thermal imaging applications.Type: GrantFiled: March 20, 2000Date of Patent: March 18, 2003Assignee: The United States of America as represented by the Secretary of the ArmyInventor: David A. Jackson
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Patent number: 6528445Abstract: Disclosed is a dielectric ceramic composition suitable for use in planar or multilayer type electronic parts containing inner conductors, for the fabrication of which simultaneously sintering base materials and conductors is required.Type: GrantFiled: January 22, 2001Date of Patent: March 4, 2003Inventors: Kug Sun Hong, Jung-Kun Lee, Dong-Wan Kim, Hyun-Woo Jung, Jeong-Ryeol Kim, Sang-Gu Kang, Do-Kyun Kwon
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Patent number: 6522521Abstract: A dielectric ceramic compact is provided which can decrease loss and heat generation under high frequency and high voltage or large current conditions, which exhibits a stable insulating resistance by AC or DC loading, and which can form a laminated ceramic capacitor using nickel or the like as an internal electrode material. The reduction-resistant dielectric ceramic compact is formed of an auxiliary sintering agent and a solid solution containing barium titanate as a primary component represented by the formula ABO3+aR+bM, where R is a compound containing an element such as La, and M is a compound containing an element such as Mn. In addition, 1.000<A/B≦1.035, 0.005≦a≦0.12, and 0.005≦b≦0.12. Furthermore, in the ceramic, the crystalline axis ratio c/a obtained by x-ray diffraction in a temperature range of −25° C. or above satisfies 1.000≦c/a≦1.Type: GrantFiled: July 31, 2001Date of Patent: February 18, 2003Assignee: Murata Manufacturing Co., Ltd.Inventors: Shinobu Mizuno, Hisashi Miki, Harunobu Sano
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Patent number: 6517931Abstract: The present invention provides an electrode ink composition and a method of using the same. The ink comprises a silver powder, a vehicle and an inhibitor. The silver powder is preferably free of palladium and gold and comprises particles having a maximum particle size of less than or equal to about 1 &mgr;m. The inhibitor comprises a powdered ceramic metal oxide composition comprising particles having a maximum particle size of less than or equal to about 0.9 &mgr;m.Type: GrantFiled: October 15, 2001Date of Patent: February 11, 2003Assignee: Ferro CorporationInventor: Bo Fu
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Patent number: 6514894Abstract: A uniform suspension of ceramic powder and method for making the same. The suspension is prepared by mixing finely divided ceramic powder in an aqueous carrier fluid, combining with a dispersing agent, and alternatively, an organic binder when forming a slip. The ceramic powder has an average particle size of about 0.5 micron or less and is present in the suspension in a loading of up to 30% by volume of the total solids in suspension. A passivating agent is present in the carrier fluid in an amount of 0.5 to 5% by weight of the ceramic powder present for suspension and slip respectively. After the addition of a dispersant, the suspension has a Bingham yield point of less than 230 dynes/cm2 and an apparent viscosity of less than 3000 cps. A green layer produced from the slip exhibits a pore size of less than 0.5 micron.Type: GrantFiled: October 20, 2000Date of Patent: February 4, 2003Assignee: Cabot CorporationInventors: James H. Adair, Stephen A. Costantino
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Patent number: 6514895Abstract: The present invention relates to electronically tunable dielectric materials which have favorable properties for many applications, including the area of radio frequency (RF) engineering and design. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with a metal silicate phase such as Mg2SiO4. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like.Type: GrantFiled: June 15, 2000Date of Patent: February 4, 2003Assignee: Paratek Microwave, Inc.Inventors: Luna H. Chiu, Xubai Zhang, Louise Sengupta
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Publication number: 20030022784Abstract: The present invention provides barium titanate semiconductive ceramic having low specific resistance at room temperature and high withstand voltage, which fully satisfies the demand for enhancing withstand voltage. The average ceramic grain size of the barium titanate semiconductive ceramic is controlled to about 0.9 &mgr;m or less. By this control, the ceramic possesses low specific resistance at room temperature and high withstand voltage fully satisfying a recent demand for enhancing withstand voltage and may suitably used for applications such as controlling temperature and limiting current, or in exothermic devices for constant temperature. Accordingly, the barium titanate semiconductive ceramic enables an apparatus using the same to have enhanced performance and reduced size.Type: ApplicationFiled: September 13, 2002Publication date: January 30, 2003Applicant: Murata Manufacturing Co., Ltd.Inventors: Mitsutoshi Kawamoto, Hideaki Niimi, Ryouichi Urahara, Yukio Sakabe
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Patent number: 6510039Abstract: A dielectric ceramic composition includes sintered ceramic grains having a core-shell structure, wherein smaller than or equal to 50% of the grains have a domain width of twin less than 20 nm; 30% to 70% of the grains have a domain width of twin in the range from 20 nm to 50 nm; less than or equal to 50% of the grains have a domain width of twin greater than 50 nm or have no twin. A ceramic capacitor includes more than one internal electrode and one or more dielectric layers composed of a dielectric ceramic composition, each of the dielectric layers being sandwiched between two neighboring internal electrodes.Type: GrantFiled: May 22, 2002Date of Patent: January 21, 2003Assignee: Taiyo Yuden Co., Ltd.Inventors: Koichiro Morita, Tomoya Hagiwara, Youichi Mizuno
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Publication number: 20030013598Abstract: A dielectric ceramic composition includes sintered ceramic grains having a core-shell structure, wherein 50% 80% of the grains have a domain width of twin smaller than 20 nm; not greater than 30% of the grains have a domain width of twin in the range from 20 nm to 50 nm; not smaller than 10% of the grains have a domain width of twin greater than 50 nm or have no twin.Type: ApplicationFiled: May 24, 2002Publication date: January 16, 2003Applicant: Taiyo Yuden Co., Ltd.Inventors: Tomoya Hagiwara, Koichiro Morita, Youichi Mizuno
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Patent number: 6503861Abstract: There is provided a dielectric ceramic composition wherein a main crystal phase is a perovskite-type crystal phase, comprising a complex oxide which contains, as a metal element, at least a rare earth element, Al, M (M is Sr, alternatively, Sr and Ca) and Ti, and is represented by the following composition formula: aLn2OxbAl2O3cMOdBaOeTiO2 wherein Ln is a rare earth element; and a, b, c, d and e is a mole ratio in a predetermined range, and more specifically comprising a solid solution of LnAlO(x+3)/2 (3≦x≦4) and RTiO3 (R is an alkaline earth metal containing at least Sr). This composition provides a large dielectric constant ∈r and a high Q value in a high frequency region, and also lessens the variation in dielectric constant ∈r, Q value, and resonance frequency temperature coefficient &tgr;f.Type: GrantFiled: January 12, 2000Date of Patent: January 7, 2003Assignee: Kyocera CorporationInventors: Shunichi Murakawa, Yoshihiro Okawa
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Publication number: 20020197461Abstract: 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: ApplicationFiled: May 29, 2002Publication date: December 26, 2002Inventors: Minoru Takaya, Yoshiaki Akachi, Hiroyuki Uematsu, Hisashi Kobuke
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Publication number: 20020193236Abstract: A method for manufacturing spherical ceramic powder is provided. The method includes essentially a spray drying step and a sintering step. In the spray drying step, a spray nozzle is used to spray slurry containing powdered raw material consisting essentially of ceramic ingredients to form liquid droplets, and liquid contents in the liquid droplets are heated and removed to obtain ceramic granular powder. In the sintering step, the ceramic granular powder is sintered to form spherical ceramic powder. The method provides ceramic powder having a mean particle size of about 1-50 &mgr;m and a sphericity of about 0.8 or higher, which is suited for mixing with resin material to form a compound. The ceramic powder has high dispersant and filling properties against the resin material.Type: ApplicationFiled: May 29, 2002Publication date: December 19, 2002Inventors: Minoru Takaya, Yoshiaki Akachi, Tomohiro Sogabe, Hisashi Kobuke
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Publication number: 20020183190Abstract: The invention provides a dielectric ceramic composite that can be burnt at a low temperature. The dielectric ceramic composite in accordance with the invention is produced by means of adding eight kinds of chemical compounds of ZnO, SiO2, CuO, Al2O3, MgO, BaCO3, B2O3 to (BaNdSm)TiO3 and then wet-mixing them for three hours.Type: ApplicationFiled: January 24, 2002Publication date: December 5, 2002Inventors: Hitoshi Masumura, Masatoshi Kobayashi
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Publication number: 20020165080Abstract: Electronically tunable dielectric materials having favorable properties are disclosed. The electronically tunable materials include an electronically tunable dielectric phase such as barium strontium titanate in combination with at least two additional metal oxide phases. The additional metal oxide phases may include, for example, oxides of Mg, Si, Ca, Zr, Ti and Al. The electronically tunable materials may be provided in bulk, thin film and thick film forms for use in devices such as phased array antennas, tunable filters and the like. The materials are useful in many applications, including the area of radio frequency engineering and design.Type: ApplicationFiled: January 24, 2001Publication date: November 7, 2002Inventors: Louise C. Sengupta, Xubai Zhang, Luna H. Chiu
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Patent number: 6472339Abstract: The present invention provides barium titanate semiconductive ceramic having low specific resistance at room temperature and high withstand voltage, which fully satisfies the demand for enhancing withstand voltage. The average ceramic grain size of the barium titanate semiconductive ceramic is controlled to about 0.9 &mgr;m or less. By this control, the ceramic possesses low specific resistance at room temperature and high withstand voltage fully satisfying a recent demand for enhancing withstand voltage and may suitably used for applications such as controlling temperature and limiting current, or in exothermic devices for constant temperature. Accordingly, the barium titanate semiconductive ceramic enables an apparatus using the same to have enhanced performance and reduced size.Type: GrantFiled: September 18, 1998Date of Patent: October 29, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Mitsutoshi Kawamoto, Hideaki Niimi, Ryouichi Urahara, Yukio Sakabe
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Publication number: 20020151430Abstract: An electric-field-inducible deformable porcelain material is provided, comprising a main component BaTiO3, with 0.05 to 2 wt % of at least one selected from Mn, Cu and Co in terms of a metal added thereto. The crystal phase in the porcelain is a single perovskite phase, and the value of the transversal electric-field-inducible deformation is 300×10−6 or more in the field strength of 2000 V/mm. It is presumed that the amount of the rotating 90° domain becomes greater, and the electric-field-induced deformation due to this is increased. Thus, a sufficient displacement amount as a piezoelectric material is obtained.Type: ApplicationFiled: April 4, 2002Publication date: October 17, 2002Applicant: NGK Insulator, Ltd.Inventors: Hirofumi Yamaguchi, Toshikatsu Kashiwaya
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Publication number: 20020137622Abstract: A dielectric ceramic composition having high static capacitance and high dielectric constant and satisfying X7R characteristics and a multilayer ceramic capacitor using the same is provided. The dielectric ceramic composition comprises barium titanate as a main component, and comprises magnesium oxide, dysprosium oxide, barium oxide, calcium oxide, and vanadium oxide, as subcomponents, wherein magnesium oxide converted into MgO is 1 to 3 mol, dysprosium oxide converted into Dy2O3 is 1 to 5 mol, total of barium oxide and calcium oxide converted into BaO and CaO, respectively, is 0.1 to 5 mol, and vanadium oxide converted into V2O5 is 0.01 to 0.1 mol, when barium titanate converted into BaTiO3 is 100 mol.Type: ApplicationFiled: December 13, 2001Publication date: September 26, 2002Inventors: Kouji Tokita, Hideki Sakai, Shuuji Aisawa, Tadahiko Horiguchi
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Patent number: 6455454Abstract: Provided is a semiconductor ceramic and a semiconductor ceramic element each having a room temperature specific resistance of 3 &OHgr;·cm or lower and a resistance temperature characteristic of 9%/° C. or more. The semiconductor ceramic is characterized in that the ratio R1/(R1+R2), in which R1 is the transgranular resistance value of the crystal particles and R2 is the intergranular resistance value of the crystal particles and R1+R2 is the overall resistance value representing the sum of R1 and R2, is about 0.35 to 0.85.Type: GrantFiled: April 28, 2000Date of Patent: September 24, 2002Assignee: Murata Manufacturing Co. Ltd.Inventors: Yasuhiro Nabika, Tetsukazu Okamoto, Toshiharu Hirota
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Publication number: 20020132721Abstract: The invention comprises ferroelectric vapor deposition targets and to methods of making ferroelectric vapor deposition targets. In one implementation, a ferroelectric physical vapor deposition target has a predominate grain size of less than or equal to 1.0 micron, and has a density of at least 95% of maximum theoretical density. In one implementation, a method of making a ferroelectric physical vapor deposition target includes positioning a prereacted ferroelectric powder within a hot press cavity. The prereacted ferroelectric powder predominately includes individual prereacted ferroelectric particles having a maximum straight linear dimension of less than or equal to about 100 nanometers. The prereacted ferroelectric powder is hot pressed within the cavity into a physical vapor deposition target of desired shape having a density of at least about 95% of maximum theoretical density and a predominate maximum grain size which is less than or equal to 1.0 micron.Type: ApplicationFiled: May 8, 2002Publication date: September 19, 2002Applicant: Honeywell International Inc.Inventors: Jianxing Li, Tim Scott, Tamara White
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Patent number: 6451222Abstract: The invention comprises ferroelectric vapor deposition targets and to methods of making ferroelectric vapor deposition targets. In one implementation, a ferroelectric physical vapor deposition target has a predominate grain size of less than or equal to 1.0 micron, and has a density of at least 95% of maximum theoretical density. In one implementation, a method of making a ferroelectric physical vapor deposition target includes positioning a prereacted ferroelectric powder within a hot press cavity. The prereacted ferroelectric powder predominately includes individual prereacted ferroelectric particles having a maximum straight linear dimension of less than or equal to about 100 nanometers. The prereacted ferroelectric powder is hot pressed within the cavity into a physical vapor deposition target of desired shape having a density of at least about 95% of maximum theoretical density and a predominate maximum grain size which is less than or equal to 1.0 micron.Type: GrantFiled: December 16, 1999Date of Patent: September 17, 2002Assignee: Honeywell International Inc.Inventors: Jianxing Li, Tim Scott, Tamara White
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Patent number: 6444336Abstract: A dielectric composite material comprising at least two crystal phases of different components with TiO2 as a first component and a material selected from the group consisting of Ba1−xSrxTiO3 where x is from 0.3 to 0.7, Pb1−xCaxTiO3 where x is from 0.4 to 0.7, Sr1−xPbxTiO3 where x is from 0.2 to 0.4, Ba1−xCdxTiO3 where x is from 0.02 to 0.1, BaTi1−xZrxO3 where x is from 0.2 to 0.3, BaTi1−xSnxO3 where x is from 0.15 to 0.3, BaTi1−xHfxO3 where x is from 0.24 to 0.3, Pb1−1.3xLaxTiO3+0.2x where x is from 0.23 to 0.3, (BaTiO3)x(PbFeo0.5Nb0.5O3)1−x where x is from 0.75 to 0.9, (PbTiO3)−(PbCo0.5W0.5O3)1−x where x is from 0.1 to 0.45, (PbTiO3)x(PbMg0.5W0.5O3)1−x where x is from 0.2 to 0.4, and (PbTiO3)x(PbFe0.5Ta0.5O3)1−x where x is from 0 to 0.2, as the second component is described. The dielectric composite material can be formed as a thin film upon suitable substrates.Type: GrantFiled: December 21, 2000Date of Patent: September 3, 2002Assignee: The Regents of the University of CaliforniaInventors: Quanxi Jia, Brady J. Gibbons, Alp T. Findikoglu, Bae Ho Park
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Patent number: 6436862Abstract: A method for manufacturing a powdered raw material of a basic powdered dielectric ceramic composition having compounds containing metal elements thereon. The method comprises the steps of dispersing a basic powdered dielectric ceramic composition in water to form a slurry, adding a silicon compound to the slurry to coat the powder, adding a solution containing the metal elements and a precipitating agent reactive therewith to form a precipitate, while the slurry is being stirred, and rinsing and drying the slurry.Type: GrantFiled: December 29, 1999Date of Patent: August 20, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Masuhisa Hirota, Shozo Kojima, Masami Yabuuchi
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Patent number: 6432558Abstract: A semiconductor ceramic device comprises a body composed of a semiconductor ceramic having a positive resistance-temperature coefficient primarily composed of barium titanate and electrodes provided on the body, in which the resistance-temperature coefficient is 9%/° C. or more, resistivity is 3.5 ∩·cm or less, and withstand voltage is 50 V/mm or more. As the semiconductor ceramic forming the body provided in a thermistor having positive resistance-temperature characteristics, a semiconductor ceramic having a positive resistance-temperature coefficient is used, in which the semiconductor ceramic has an average particle diameter of about 7 to 12 &mgr;m and comprises barium titanate as a major component and sodium in an amount of about 70 ppm or less on a weight basis.Type: GrantFiled: August 8, 2000Date of Patent: August 13, 2002Assignee: Murata Manufacturing Co. Ltd.Inventors: Yasuhiro Nabika, Tetsukazu Okamoto, Toshiharu Hirota, Yoshitaka Nagao
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Patent number: 6429163Abstract: The present invention provides a dielectric ceramic composition, a capacitor using the composition and the producing method, of having a lower dielectric loss and a stable characteristics in high frequency bandwidth, and enabling to use a base metal or a carbon-based material as an electrode material by allowing sintering at a low temperate, thereby resulting in lower cost. The dielectric ceramic composition according to present invention, is characterized in comprising a main component of formula SrxBa1−x(ZryTi1−y) O3 (where 0.8≦x≦1; 0.9≦y≦1) to which MnO2 of 0.05-15 wt %, at least one of 0.001-5 wt % selected from the group consisting of Bi2O3PbO and Sb2O3 and a glass component of 0.5-15 wt % are added based on the weight of the main component.Type: GrantFiled: March 30, 2001Date of Patent: August 6, 2002Assignee: Samsung Electro-Mechanics Co., Ltd.Inventors: Jong Hee Kim, Shigehiro Fujino, Nobutake Hirai