And Trivalent Metal Oxide Patents (Class 501/139)
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Patent number: 6340649Abstract: The composition of dielectric ceramics is formed in that a main component is expressed with a general formula of xBaO·yNd2O3·zTiO2 (provided that the general formula has the relation of 6≦x≦23, 13≦y≦30, 64≦z≦68 and x+y+z=100), and in relation with the main components, sub-components are contained of Cu oxides 0.1 to 3.0 wt % in terms of CuO, Zn oxide 0.1 to 4.0 wt % in terms of ZnO, and B oxide 0.1 to 3.0 wt % in term of B2O3. It is preferable that Ag 0.3 to 1.5 wt % is contained as the sub-component.Type: GrantFiled: March 15, 2000Date of Patent: January 22, 2002Assignee: TDK CorporationInventors: Tomoaki Kawata, Akira Nakamura, Toshio Sakurai, Aya Fukuhara
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Patent number: 6335302Abstract: A dielectric composition containing at least calcium titanate, strontium titanate, and barium titanate, wherein at least the molar ratios of composition of the three are such that the molar ratio of composition (P) of calcium titanate is 0.5 to 0.85, the molar ratio of composition (Q) of strontium titanate is 0.05 to 0.4, and the molar ratio of composition (R) of barium titanate is 0.1 to 0.2 (where, P+Q+R=1).Type: GrantFiled: January 12, 2000Date of Patent: January 1, 2002Assignee: TDK CorporationInventors: Shigeki Satoh, Yoshinori Fujikawa, Akiko Nagai, Kaori Masumiya
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Patent number: 6331499Abstract: A microwave dielectric ceramic composition exhibiting excellent relative permitting (∈) and high Qf-value, enabling the temperature coefficient of resonance frequency to be easily adjusted, and being best suited for a filter having cavities made of, e.g., iron or copper exhibiting a large temperature coefficient of resonance frequency. The ceramic is of a BaO—TiO2—Nd2O3—Sm2O3 ceramic, type wherein Nd2O3 is partly substituted by Bi2O3, Nd2O3 is Partly substituted by Ln2O3 (where Ln is La, Ce or Pr) and, the above substituted Ln2O3 is partly substituted by EU2O3 to improve the properties so that ∈ is 82.5 to 92.5, Qf is 6000 to 7300 GHz and &tgr;f is 10-20 ppm/° C. This makes it possible to impart favorable electric characteristics to resonance cavities of various materials and sizes.Type: GrantFiled: February 9, 2001Date of Patent: December 18, 2001Assignee: Sumitomo Special Metals Co., Ltd.Inventors: Takeshi Shimada, Keisuke Kageyama, Soyoko Ando
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Patent number: 6319871Abstract: Disclosed is a dielectric material comprising: a main ingredient having a composition represented by xBaO-yRE2O3-zTiO2, wherein RE represents at least one rare earth element, and x+y+z=100 mol %; at least one alkali metal oxide; and an ingredient derived from an oxygen supplying agent which releases oxygen on heating.Type: GrantFiled: August 30, 1999Date of Patent: November 20, 2001Assignee: NGK Spark Plug Co., Ltd.Inventors: Motohiko Sato, Hitoshi Yokoi, Kazushige Ohbayashi
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Publication number: 20010036896Abstract: The present invention provides a dielectric ceramic composition whose electrostatic capacity has an excellently low temperature dependence; which can be fired in a reducing atmosphere; and which is advantageously used in a laminated ceramic capacitor having an internal electrode formed of a base metal such as nickel or nickel alloy. The dielectric ceramic composition is represented by the following formula: {Ba1-xCaxO}mTiO2+&agr;MgO+&bgr;MnO, wherein 0.001≦&agr;≦0.05; 0.001≦&bgr;≦0.025; 1.000<m≦1.035; and 0.02≦x≦0.15.Type: ApplicationFiled: February 2, 2001Publication date: November 1, 2001Applicant: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Wada, Jun Ikeda, Takashi Hiramatsu, Yukio Hamaji
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Patent number: 6291380Abstract: A dielectric material comprising: a main component represented by the composition formula (1-&agr;) {(Ba1−xCaxO)A (Ti1−yZryO2)B}·&agr;L2O3, wherein 0.0005≦&agr;≦0.015, 0.03≦x≦0.15, 0.01 ≦y≦0.25, 1.00≦A/B≦1.02, L: at least one component selected from the group consisting of lanthanide; and subsidiary components including 0.01 to 1.0% by weight of MnO and 0.005 to 0.5% by weight of an oxide containing Al2O3 as a major component; and further 0.01 to 0.4 total % by weight of at least one oxide selected from the group of oxides of V, Nb, Ta, Mo and W, and a small size, large capacitance, multi-layer ceramic chip capacitor comprising said dielectric material.Type: GrantFiled: March 15, 2000Date of Patent: September 18, 2001Assignee: Rohm Co., Ltd.Inventors: Hiroki Yokoi, Takeshi Sawano, Takashi Hashiguchi
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Patent number: 6274526Abstract: A dielectric ceramic composition for microwave which comprises a basic composition represented by compositional formula: 2aBaO—bLn2O3—cBi2O3—2dTiO2, wherein Ln2O3 represents (eNd2O3+fSm2O3+gEu2O3); a+b+c+d=l; and e+f+g=1, in which 0.0913<a≦0.1429, 0.2098<b<0.3003, 0<c<0.0856, 0.5714≦d<0.6043, 0.27<e<0.80, 0.18<f<0.70, 0<g<0.20, and 0.15<a/d<0.25.Type: GrantFiled: November 21, 2000Date of Patent: August 14, 2001Assignee: Ube Industries, Ltd.Inventors: Takafumi Kawano, Koichi Fukuda
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Patent number: 6268054Abstract: Barium titanate-based particles having a coating comprising an oxide, hydrous oxide, hydroxide or organic acid salt of a metal other than barium or titanium, wherein at least 90 percent of said particles have a particle size less than 0.9 micrometer when said particles are dispersed by high shear mixing, useful in the fabrication of thin, fine-grained dielectric layers for multilayer ceramic capacitors with high breakdown voltage.Type: GrantFiled: September 4, 1997Date of Patent: July 31, 2001Assignee: Cabot CorporationInventors: Stephen A. Costantino, Robert A. Hard, Sridhar Venigalla
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Publication number: 20010008867Abstract: A ceramic for the PTC thermistor having a resistivity at room temperature of 5 &OHgr;·cm or less, static withstanding voltage of 60 V/mm or more and temperature resistance coefficient of 9.0%/° C., having small dispersion of the resistance, is composed of principal components of about 30 to 97 mol % of BaTiO3, about 1 to 50 mol % of PbTiO3, about 1 to 30 mol % of SrTiO3 and about 1 to 25 mol % of CaTiO3 (the total content of them being 100 mol %), as well as about 0.1 to 0.3 mole of Sm, about 0.01 to 0.03 mole of Mn and 0 to about 2.0 mole of Si relative to 100 moles of the principal components, the composite material being preferably heat-treated in an oxidative atmosphere after being fired in a reducing or neutral atmosphere for obtaining the ceramic.Type: ApplicationFiled: July 23, 1999Publication date: July 19, 2001Inventors: YASUHIRO NABIKA, TETSUKAZU OKAMOTO, TOSHIHARU HIROTA, NORIYUKI YAMAMOTO
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Patent number: 6251816Abstract: Temperature compensating capacitors and dielectric ceramic powder compositions therefor are disclosed, based upon a dual-component barium borate and zinc silicate sintering flux. The precursor dielectric ceramic powders can include (1−m) BaTiO3+(m) CaZrO3 (BTCZ composition), with m ranging from 20 mole percent to 35 mole percent, xBaO.yTiO2.zRE2O3 (rare earth composition), (RE being a rare earth metal), with x ranging from 0 m % to 30 m %, y ranging from 45 m % to 95 m %, and z ranging from 5 m % to 50 m %, or a combination of the BTCZ and rare earth composition in varying weight percents. The effective range of B2O3 in the barium borate ranges from 0.029 w % to 2.75 w % of the total dielectric composition, whereas the effective range of SiO2 in the zinc silicate ranges from 0.08 w % to 1.42 w % of the total dielectric composition.Type: GrantFiled: December 31, 1998Date of Patent: June 26, 2001Assignee: MRA Laboratories, Inc.Inventors: Galeb H. Maher, Samir G. Maher
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Patent number: 6245433Abstract: A dielectric ceramic composition containing a primary component represented by the following formula: {BaO}mTiO2+&agr;M2O3+&bgr;R2O3+&ggr;BaZrO3+gMgO+hMnO wherein M2O3 is at least one of Sc2O3 or Y2O3; R2O3 is at least one member selected from the group consisting of Eu2O3, Gd2O3, Tb2O3. Dy2O3, Ho2O3, Er2O3, Tm2O3 and Yb2O3; &agr;, &bgr;, &ggr;, g or h represent a mole ratio and satisfy specified relations; and silicon oxide as an auxiliary component in an amount of 0.2-5.0 mol as SiO2, with respect to 100 mol of the primary component.Type: GrantFiled: May 12, 1999Date of Patent: June 12, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Tomoyuki Nakamura, Shinobu Mizuno, Harunobu Sano
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Patent number: 6231779Abstract: A single crystal perovskite material is provided having the formula, M&agr;Bi&bgr;M′&ggr;M″&dgr;O3±z, where M is one or more of Na, K, Rb and Cs; M′ is one or more of Ca, Sr, Ba, Pb, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M″ is one or more of Ti, Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta and W; where z≦0.1; 0.9≦&dgr;≦1.1; &agr;, &bgr; and &ggr; are greater than zero; and (&agr;+&bgr;+&ggr;) is in the range of about 0.75 to 1.1. A perovskite material of the formula, Na&ohgr;M&agr;Bi&bgr;M′&ggr;M″&dgr;O3±z, is provided where M is one or more of K, Rb and Cs; 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; M″ is one or more of Ti, Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta and W; where z≦0.1; 0.9≦&dgr;≦1.1; &agr;, &bgr; and &ggr; are greater than zero; and (&agr;+&bgr;+&ggr;) is in the range of about 0.75 to 1.1.Type: GrantFiled: October 19, 1998Date of Patent: May 15, 2001Assignee: Massachusetts Institute of TechnologyInventors: Yet-Ming Chiang, Gregory W. Farrey, Nesbitt W. Hagood, IV, Andrey Soukhojak, Haifeng Wang
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Patent number: 6225250Abstract: The present invention provides a dielectric ceramic composition whose electrostatic capacity has an excellently low temperature dependence; which can be fired in a reducing atmosphere; and which is advantageously used in a laminated ceramic capacitor having an internal electrode formed of a base metal such as nickel or nickel alloy. The dielectric ceramic composition is represented by the following formula: {Ba1−xCaxO}mTiO2+&agr;MgO+&bgr;MnO, wherein 0.001≦&agr;≦0.05; 0.001≦&bgr;≦0.025; 1.000<m≦1.035; and 0.02≦x≦0.15.Type: GrantFiled: February 17, 1999Date of Patent: May 1, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Nobuyuki Wada, Jun Ikeda, Takashi Hiramatsu, Yukio Hamaji
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Patent number: 6221800Abstract: A method of producing a PTC semiconducting ceramic which entails preparing the calcine of a main composition of barium titanate-based semiconductor containing substantially no Si and having BaTiO3 as a main component thereof, preparing additive compositions, Ba2TiSi2O8 and BanTimOn+2m (1≦n≦4,2≦m≦13, n<m), respectively, compounding the calcine of the main composition and the additive compositions and mixing them, and then subjecting them to formal firing. The obtained product exhibits excellent electrical characteristics, which are not influenced by fluctuations in conditions of production.Type: GrantFiled: April 23, 1999Date of Patent: April 24, 2001Assignee: TDK CorporationInventors: Chihiro Takahashi, Shigeki Sato
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Patent number: 6204069Abstract: A preferred embodiment of this invention comprises a conductive lightly donor doped perovskite layer (e.g. lightly La doped BST 34), and a high-dielectric-constant material layer (e.g. undoped BST 36) overlaying the conductive lightly donor doped perovskite layer. The conductive lightly donor doped perovskite layer provides a substantially chemically and structurally stable electrical connection to the high-dielectric-constant material layer. A lightly donor doped perovskite generally has much less resistance than undoped, acceptor doped, or heavily donor doped HDC materials. The amount of donor doping to make the material conductive (or resistive) is normally dependent on the process conditions (e.g. temperature, atmosphere, grain size, film thickness and composition). This resistivity may be further decreased if the perovskite is exposed to reducing conditions.Type: GrantFiled: October 3, 1994Date of Patent: March 20, 2001Assignee: Texas Instruments IncorporatedInventors: Scott R. Summerfelt, Howard R. Beratan, Bruce Gnade
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Patent number: 6195250Abstract: Laminated ceramic parts such as a laminated ceramic condenser and a laminated LC filter are formed by using a temperature compensating dielectric ceramic composition having a high relative dielectric constant and a high Q value, and which can be sintered at a relatively low temperature during the manufacturing processes, without causing any undesired variations in ceramic properties during the sintering treatment. The composition includes 100 parts by weight of a main component having a mole composition ratio (BaO, TiO2, Re2O3) shown in a ternary composition diagram indicated by an area surrounded by point A (39.5. 59.5, 1), point B (1, 59.5, 39.5), point C (1, 85, 14) and point D (14, 85, 1); about 25 parts by weight or less of a lead free B2O3—SiO2 glass; at least one of V oxide (the content as V2O5 being about 10 parts by weight or less) and W oxide (the content as WO3 being about 20 parts by weight or less).Type: GrantFiled: September 13, 1999Date of Patent: February 27, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Hiroaki Matoba, Harunobu Sano
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Patent number: 6184165Abstract: A dielectric porcelain composition according to the present invention is composed of a main component expressed in a general formula of xBaO·y((1−t)Nd2O3·tSm2O3)·zTiO2, where 6≦x≦23, 13≦y≦30, 64≦z≦68, 0≦t<1 and x+y+z=100. The main component contains a sub component containing Cu oxide in the range of 0.1 to 3.0 wt % in terms of CuO and glass composition in the range of 2.0 to 10 wt %. Further, 90 wt % or more of the glass composition is at least one selected from SiO2, B2O3, MgO, BaO, SrO, ZnO and CaO, in the ranges of: 5 wt %≦SiO2≦15 wt %; 15 wt %≦B2O3≦25 wt %; 50 wt %≦(MgO+BaO+SrO+ZnO+CaO)≦80 wt %; 90 wt %≦(SiO2+B2O3+MgO+BaO+SrO+ZnO+CaO)≦100 wt %.Type: GrantFiled: July 15, 1999Date of Patent: February 6, 2001Assignee: TDK CorporationInventor: Tomoaki Kawata
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Patent number: 6174831Abstract: An object of the present invention is to provide a dielectric ceramic composition in which a volume changing ratio of the electrostatic capacity is within ±0.3% over a wide temperature range of −55 to +125° C., it satisfies the NPO characteristics regulated by EIA standard, the dielectric constant is high as 75 or more and the Q value of 2000 or higher and it is capable of subjecting to sintering at a low temperature of 1100 to 1150° C. The dielectric ceramic composition of the present invention is a (Ba Ca Sr Nd Gd)TiO3 series composition and to the composition was added and contained 1.0 to 5.0% by weight of ZnSiTiO5, 1.0 to 5.0% by weight of ZnSi2TiO7 or 1.0 to 5.0% by weight of CaSiTiO5 based on the weight of the composition.Type: GrantFiled: May 25, 1999Date of Patent: January 16, 2001Assignee: U.S. Philips CorporationInventors: Yukiko Furukawa, Hitoshi Masumura
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Patent number: 6169049Abstract: Hydrothermal BaTiO3 crystallites were coated with Bismuth solutions prepared from Bismuth metal-organics and anhydrous solvents. The Bismuth metal-organics were Bi 2-ethylhexanoate and Bi-neodecanoate. Bismuth oxide was also used as a comparison to the Bismuth solutions. BaTiO3 ceramics with either 3.0 wt % equivalent Bismuth oxide or 5.0 wt % equivalent Bismuth oxide were made by sintering the compacts between 700° C. and 1000° C. BaTiO3 ceramics that were coated by Bi-neodecanoate densified >90% theoretical as low as 800° C. for 3.0 wt % equivalent Bi2O3. Average grain sizes of 0.2-0.4 &mgr;m were observed for Bi-coated BaTiO3 ceramics, for sintering temperatures below 950° C. Dielectric K versus temperature measurements of Bismuth-coated BaTiO3 ceramics, sintered in the lower temperature ranges, showed consistently superior dielectric characteristics.Type: GrantFiled: April 28, 1997Date of Patent: January 2, 2001Inventors: John P. Witham, Clive A. Randall, Umesh Kumar, Ulagaraj Selvaraj, Sea-Fue Wang, Joseph P. Dougherty
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Patent number: 6165927Abstract: A dielectric material based on BaO-RE.sub.2 O.sub.3 -TiO.sub.2 is disclosed, which has a relatively high relative permittivity .epsilon..sub.r, a small absolute value of the temperature coefficient of resonance frequency .tau..sub.f and a high coefficient of unloaded quality Q.sub.u. Processes for producing the dielectric material are also disclosed. The dielectric material comprises 100 parts by weight of main ingredients having a composition represented by xBaO-yRE.sub.2 O.sub.3 -zTiO.sub.2 (wherein RE represents a rare earth element and x+y+z=100) and up to 5 parts by weight of at least one alkali metal oxide. This alkali metal oxide serves to improve .epsilon..sub.r and Q.sub.u without a considerable sacrifice of .tau..sub.f. The RE preferably consists of samarium or a combination of samarium with neodymium and/or lanthanum.Type: GrantFiled: April 24, 1998Date of Patent: December 26, 2000Assignee: NGK Spark Plug Co., Ltd.Inventors: Motohiko Sato, Hitoshi Yokoi, Kazushige Ohbayashi
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Patent number: 6139780Abstract: A charge storage device is resistant to degradation in reducing atmospheres for use in dynamic random access memories. The device consists of a dielectric layer that is sandwiched between two electrodes and grown on a suitable substrate such as silicon or silicon coated with silicon dioxide. The dielectric layer is either (a) a modified composition of Ba.sub.x Sr.sub.1-x TiO.sub.3, 0<x<1 (BST) doped with acceptor type dopants such as Mn, Co, Mg, Cr, Ga and Fe ions as the dielectric layer in the capacitor; the acceptor ions can occupy the titanium sites to prevent the formation of Ti.sup.3+ and inhibit the formation of conductive BST by compensating the charges of the oxygen vacancies, and by trapping the free electrons more freely than Ti.sup.4+, or (b) modified dielectric compositions with alkaline-earth ions with compositions [(Ba.sub.x M.sub.x)O].sub.y TiO.sub.2 (where M can be Ca, Sr or Mg) with the value of y slightly larger than unity.Type: GrantFiled: May 28, 1998Date of Patent: October 31, 2000Assignee: Sharp Kabushiki KaishaInventors: Seshu B. Desu, Carlos A. Suchicital, Dilip P. Vijay
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Patent number: 6126743Abstract: Disclosed is a process for producing dielectrics which satisfy the formula of:WXMO.sub.3 --(l--w)(XO.sub.y --aGO.sub.z)wherein the symbols are as defined in the specification, which comprises mixing an oxide of X, an oxide of M and an oxide of G or compounds capable of being converted to the above oxides so that the region occupied by the oxides or the compounds is smaller than 0.1 .mu.m in diameter and then, firing the mixture by heating at a temperature at which the mixture can be converted to oxides. A process for producing fine single crystal powders and a thin film capacitor are also disclosed.Type: GrantFiled: January 29, 1996Date of Patent: October 3, 2000Assignee: Sumitomo Chemical Company, LimitedInventors: Kunio Saegusa, Yutaka Suzuki
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Patent number: 6107228Abstract: A dielectric ceramic composition which has a high dielectric constant and a high Q value, as well as excellent temperature stability, and which is sinterable at a relatively low temperature. The dielectric ceramic composition of the present invention is formed of a mixture of a BaO--TiO.sub.2 --REO.sub.3/2 --BiO.sub.3 ceramic composition wherein RE represents a rare earth element, and a glass composition. The glass composition contains about 13-50 wt. % SiO.sub.2, about 3-30 wt. % B.sub.2 O.sub.3, about 40-80 wt. % alkaline earth metal oxide and about 0.1-10 wt. % Li.sub.2 O.Type: GrantFiled: February 22, 1999Date of Patent: August 22, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Yasutaka Sugimoto, Hiroshi Takagi
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Patent number: 6107227Abstract: A high purity dielectric ceramic composition is disclosed. This composition provides improved electrical properties in the form of ultra-high electrical Q, a low (T.sub.f) property and a high dielectric constant (K). This composition is also amenable to large scale manufacturing processes and operations. The composition provides a multi-oxide dielectric with BaO--Nd.sub.2 O--Sm.sub.2 O.sub.3 --TiO.sub.2 --La.sub.2 O.sub.3 Bi.sub.2 O.sub.3 and ZnO as constituents. The composition materials effectively provide these desirable properties in a custom composition of various oxide materials advantageously including samarium oxide (Sm.sub.2 O.sub.3).Type: GrantFiled: August 3, 1998Date of Patent: August 22, 2000Assignee: CTS CorporationInventors: Jeffrey Jacquin, Dean A. Anderson, Randy Rose
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Patent number: 6103385Abstract: The ceramic electronic part has a ceramic material and an electrode formed on the surface of the ceramic material. The ceramic material has rod-shaped particles formed projecting from the surface thereof, the rod-shaped particles having an aspect ratio (a long axis/short axis ratio) of from 3 to 30. The ceramic material is formed using a dielectric ceramic composition containing, as a major component, a composite oxide which, for example, comprises an oxide of barium (Ba), an oxide of titanium (Ti) an oxide of at least one rare earth element and one or both of an oxide of bismuth (Bi) and an oxide of lead (Pb).Type: GrantFiled: April 23, 1998Date of Patent: August 15, 2000Assignee: Taiyo Yuden Co., Ltd.Inventor: Nobuhiro Sasaki
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Patent number: 6087288Abstract: A dielectric ceramic composition including a compound of the BaTiO.sub.3 --Nb.sub.2 O.sub.5 --Co.sub.3 O.sub.4 group. The composition contains 1.1-1.4 mo. % of in total Nb.sub.2 O.sub.5 and Co.sub.3 O.sub.4 wherein the molar ration of Nb.sub.2 O.sub.5 to Co.sub.3 O.sub.4 is between 4.4 and 5.0. The composition contains 0.02-0.06% by weight of MnCO.sub.3, 0.02-0.25% by weight of Nd.sub.2 O.sub.3, 0.02-0.10% by weight of Y.sub.2 O.sub.3 and 0.05-0.15% by weight of Al.sub.2 O.sub.3 with respect to the weight of the composition. Laminated ceramic capacitors including the dielectric ceramic material show a capacity changing ration which is less than 15% in the temperature range between -55.degree. C. and +125.degree. C., a dielectric loss which is smaller than 3.5% and a dielectric constant which is 4000 or more.Type: GrantFiled: December 1, 1998Date of Patent: July 11, 2000Assignee: U.S. Philips CorporationInventors: Hitoshi Masumura, Kiyotaka Saito, Atsuko Fujii
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Patent number: 6087287Abstract: A dielectric ceramic essentially in the form of an aggregate of crystal grains each having a ferroelectric core enclosed in a paraelectric shell. The shells are created by thermal diffusion of magnesium into the crystal grains. Through control of the firing temperature and time the thicknesses of the shells are confined in the range of approximately 5-30% of the average grain size. The resulting ceramic is low in dielectric constant and favorable in temperature characteristic of capacitance, making it suitable for use in laminated capacitors.Type: GrantFiled: September 13, 1999Date of Patent: July 11, 2000Assignee: Taiyo Yuden Co., Ltd.Inventors: Yoshiaki Iguchi, Mutsumi Honda, Hiroshi Kishi
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Patent number: 6074971Abstract: Ceramic ferroelectric composite materials comprising barium strontium titte/magnesium and oxygen-containing compound composite further doped with rare earth (lanthanide) oxides. More particularly, these inventive composites are comprised of Ba.sub.1-x Sr.sub.x TiO.sub.3 /Mg--O based compound/rare earth oxide composite, wherein x is greater than or equal to 0.0 but less than or equal to 1.0, and wherein the weight ratio of BSTO to Mg compound may range from 99.75-20 wt. % BSTO to 0.25-80 wt. % Mg compound, and wherein said rare earth oxide additive comprises less than about 10 mole percent of the composite. The rare earth oxides of the composite include all oxides of the lanthanide series elements including scandium and yttrium, as well as combinations thereof. The magnesium-based compound may be selected from the group consisting of MgO, MgZrO.sub.3, MgZrSrTiO.sub.3, MgTiO.sub.3, and MgCO.sub.3.Type: GrantFiled: November 13, 1998Date of Patent: June 13, 2000Assignee: The United States of America as represented by the Secretary of the ArmyInventors: Luna H. Chiu, Louise C. Sengupta, Steven Stowell, Somnath Sengupta, Jennifer Synowczynski
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Patent number: 6071842Abstract: A barium titanate-based semiconducting ceramic, which contains BaTiO.sub.3 as a main component thereof, and Ba.sub.2 TiSi.sub.2 O.sub.8 and Ba.sub.n Ti.sub.m O.sub.n+2m (1.ltoreq.n.ltoreq.4, 2.ltoreq.m.ltoreq.13, n.ltoreq.m), respectively, as trace-phase compositions, wherein the ratio of the contents of about Ba.sub.2 TiSi.sub.2 O.sub.8 and Ba.sub.n Ti.sub.m O.sub.n+2m (Ba.sub.2 TiSi.sub.2 O.sub.8 /Ba.sub.n Ti.sub.m O.sub.n+2m) as the trace-phase compositions is in the range of about 0.5 to 80.0. This semiconductive ceramic exhibits excellent voltage resistance and ensures high reliability as a product element. Moreover, it has a suitable room temperature resistivity .rho.25 for functioning as a product element.Type: GrantFiled: May 5, 1999Date of Patent: June 6, 2000Assignee: TDK CorporationInventors: Chihiro Takahashi, Shigeki Sato
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Patent number: 6063719Abstract: A novel ceramic ferrite/ferroelectric composite material having a low dissipation factor, voltage tunability, and proper impedance matching for the incident medium. The material comprises ferrites doped with the ferroelectric Barium Strontium Titanate (BSTO) or ferrites doped with the ferroelectric Barium Strontium Titanate (BSTO)/MgO. Preferred composites are magnesium ferrites doped with BSTO and magnesium ferrites doped with BSTO/MgO. Most particularly, the inventive composites are comprised of magnesium ferrites doped with Ba.sub.1-x Sr.sub.x TiO.sub.3 and magnesium ferrites doped with Ba.sub.1-x Sr.sub.x TiO.sub.3 /MgO, wherein x is greater than 0.00, but less than or equal to 0.75, and wherein the percent weight ratio of magnesium ferrite to BSTO or BSTO/MgO is 60 to 95 percent ferrite to 40 to 5 percent BSTO or 60 to 95 percent ferrite to 40 to 5 percent BSTO/MgO ferroelectric. A particularly well suited composite, i.e., one having a .mu./.di-elect cons.Type: GrantFiled: September 1, 1998Date of Patent: May 16, 2000Assignee: The United States of America as represented by the Secretary of the ArmyInventors: Louise C. Sengupta, Somnath Sengupta
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Patent number: 6058005Abstract: Disclosed is a dielectric ceramic composition containing an essential component represented by the formula, xBaO-yTiO.sub.2 -zRe.sub.2 O.sub.3, wherein x, y and z are in mol %; x+y+z=100; and (x, y, z) falls within a polygonal region defined by four points of A (39.5, 59.5, 1), B (1, 59.5, 39.5), C (1, 85, 14) and D (14, 85, 1), and further containing V, Cu and Mn as side components in an amount of about 0.1 wt. % to 15 wt. % in terms of V.sub.2 O.sub.5, in an amount not greater than 10 wt. % in terms of CuO, and in an amount not greater than 1 wt. % in terms of MnO, respectively, relative to 100 wt. % of the essential component.Type: GrantFiled: August 28, 1998Date of Patent: May 2, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Hiroaki Matoba, Harunobu Sano
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Patent number: 6051516Abstract: The present invention provides a dielectric ceramic composition containing 100 parts by weight of essential component represented by (BaO).sub.m TiO.sub.2 +M.sub.2 O.sub.3 +R.sub.2 O.sub.3 +BaZrO.sub.3 +MgO+MnO (wherein M.sub.2 O.sub.3 represents Sc.sub.2 O.sub.3 and/or at least one of Eu.sub.2 O.sub.3, Gd.sub.2 O.sub.3, Tb.sub.2 O.sub.3 and Dy.sub.2 O.sub.3) and 0.2 to 3.0 parts by weight of a side component represented by Li.sub.2 O--(Si, Ti)O.sub.2 --MO (wherein MO represents Al.sub.2 O.sub.3 and or ZrO.sub.2) or SiO.sub.2 --TiO.sub.2 --XO (wherein XO represents at least one of BaO, CaO, SrO, MgO, ZnO and MnO), and a ceramic capacitor using the same.Type: GrantFiled: July 22, 1998Date of Patent: April 18, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Shinobu Mizuno, Norihiko Sakamoto, Nobuyuki Wada
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Patent number: 6043174Abstract: Multilayer capacitors with have been made including a cadmium silicate flux by firing in a closed crucible at about 1100.degree. C. to provide a high K and smooth X7R coefficient of K with temperature, but tend to acquire a low insulation resistance in a high temperature life test under voltage. This problem was solved heretofore by the added step of a post-sinter anneal. However, the anneal step adds cost and further complexity to the manufacturing process.Type: GrantFiled: June 26, 1997Date of Patent: March 28, 2000Assignee: MRA LaboratoriesInventors: Galeb H. Maher, Veerabhadrarao Bheemineni
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Patent number: 6002578Abstract: A ceramic substrate comprises having two or more functional portions separated from each other, by providing a first region comprising a first dielectric porcelain having an insulating layer at the crystal grain boundaries of a semiconductor porcelain containing a semiconductivizing agent and a second region comprising a second dielectric porcelain with different dielectric constant from the first dielectric porcelain through the difference in amount or kind of the semiconductivizing agent from the first region.Type: GrantFiled: September 4, 1996Date of Patent: December 14, 1999Assignee: Canon Kabushiki KaishaInventors: Motoo Kumagai, Keiichi Kato
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Patent number: 5994253Abstract: A dielectric ceramic composition is comprised of a crystal structure phase of a tungsten bronze form, one titanate-barium phase or more titanate-barium phases selected from Ba.sub.2 Ti.sub.9 O.sub.20, BaTi.sub.2 O.sub.5, BaTi.sub.4 O.sub.9 and Ba.sub.4 Ti.sub.13 O.sub.30, and a fine crystal phase comprising an oxide of each of at least B, Ag and Mn, in which the crystal structure phase of the tungsten bronze form is formed with a limited amount of a compound oxide of Ba, Nd and Ti as a basic component and contains a limited amount of each of an oxide of at least Bi, Pb, Zn and Si. The dielectric ceramic composition can be fired at a temperature of 920.degree. C. or lower and sintered forming into a ceramic electronic part which has remarkably high dielectric characteristics, such as the dielectric constant of 60 or higher, the Q factor of 1,000 or higher, and the temperature coefficient .tau..epsilon.r of the relative dielectric constant .epsilon.r of .+-.60 ppm/.degree. C. or smaller.Type: GrantFiled: July 6, 1998Date of Patent: November 30, 1999Assignee: Taiyo Yuden Co., Ltd.Inventors: Nobuhiro Sasaki, Katsuyuki Horie, Hirokazu Chazono
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Patent number: 5990029Abstract: A dielectric ceramic composition of the invention comprises as major components 94 to 99 mol % of barium titanate, calculated as BaTiO.sub.3, 0.05 to 3 mol % of tantalum oxide, calculated as Ta.sub.2 O.sub.5, 0.05 to 3 mol % of niobium oxide, calculated as Nb.sub.2 O.sub.5, and 0.5 to 3 mol % of zinc oxide, calculated as ZnO, and further contains as a subordinate additive at least one of calcium zirconate, strontium zirconate and barium zirconate in a total amount of 0.2 to 5% by weight per 100 mol % of said major components, calculated as CaZrO.sub.3, SrZrO.sub.3 and BaZrO.sub.3, respectively. The dielectric ceramic composition having a high dielectric constant is most unlikely to delaminate and is suitable for a multilayered ceramic capacitor. This dielectric ceramic composition has also little, if any, capacitance change and dielectric loss over a wide temperature range of -55.degree. C. to +150.degree. C.Type: GrantFiled: February 24, 1998Date of Patent: November 23, 1999Assignee: TDK CorporationInventors: Masami Satoh, Hitoshi Tanaka
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Patent number: 5990028Abstract: A high-dielectric lead-free paste serves for the manufacture of at least one area having a high dielectric constant in a ceramic multilayer circuit. The lead-free dielectric paste is basically made of barium titanate nano powder of a suitable particle size and sinters at temperatures below 1000.degree. C., preferably in a range of 800.degree. C. to 1000.degree. C.Type: GrantFiled: September 19, 1997Date of Patent: November 23, 1999Assignee: Robert Bosch GmbHInventors: Walter Roethlingshoefer, Annette Seibold, Susumu Nishigaki
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Patent number: 5977006Abstract: A dielectric ceramic essentially in the form of an aggregate of crystal grains each having a ferroelectric core enclosed in a paraelectric shell. The shells are created by thermal diffusion of magnesium into the crystal grains. Through control of the firing temperature and time the thicknesses of the shells are confined in the range of approximately 5-30% of the average grain size. The resulting ceramic is low in dielectric constant and favorable in temperature characteristic of capacitance, making it suitable for use in laminated capacitors.Type: GrantFiled: May 6, 1998Date of Patent: November 2, 1999Assignee: Taiyo Yuden Co., Ltd.Inventors: Yoshiaki Iguchi, Mutsumi Honda, Hiroshi Kishi
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Patent number: 5958285Abstract: Disclosed is a sintered piezoelectric ceramic which is resistant to the high voltage for polarization with no dielectric breakdown and has good moisture resistance. When a plurality of the ceramics are fired, they are prevented from being fused and combined together. The production costs of the ceramic are low. The sintered piezoelectric ceramic comprises particulate or agglomerate zirconia grains dispersed in piezoelectric ceramic grains, in which the mean grain size of the piezoelectric ceramic grains is smaller than that of the zirconia grains.Type: GrantFiled: June 26, 1998Date of Patent: September 28, 1999Assignee: Murata Mnufacturing Co., Ltd.Inventors: Koichi Kawano, Kazuya Kamada
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Patent number: 5874379Abstract: An improved dielectric thin film and a capacitor with the same for a semiconductor and a fabrication method thereof capable of preventing leakage current in operation, which dielectric thin film includes (Ba, Sr)TiO.sub.3 containing Ta, and which the capacitor includes a substrate; an interlayer insulation layer formed on a substrate, thereby exposing a predetermined portion of the substrate to the outside; a lower electrode formed on a predetermined portion of the interlayer insulation layer including the exposed portion of the substrate; a dielectric thin film consisting of (Ba, Sr)TiO.sub.3 containing Ta and formed on the interlayer insulation film including the lower electrode; and an upper electrode formed on the dielectric thin film.Type: GrantFiled: March 4, 1996Date of Patent: February 23, 1999Assignee: LG Semicon Co., Ltd.Inventors: Seung-Ki Joo, Jae-Hyun Joo
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Patent number: 5866494Abstract: The present invention relates to a laminated ceramic composition which has a high dielectric constant and a low decrease rate of dielectric constant at DC bias, which can be used for bypass of computer module IC. The present invention provides a ceramic condenser composition which comprises BaTiO.sub.3, TiO.sub.2, CeO.sub.2 and Sm.sub.2 O.sub.3 by the molar ratio to satisfy the equation of (1-X-Y)BaTiO.sub.3 -X(CeO.sub.2)-Y(Sm.sub.2 O.sub.3)-(1.5X+3Y)TiO.sub.2 (wherein, 0.01<X+Y<0.05 and 0.015<1.5X+3Y<0.15). The composition has an excellent dielectric characteristics, since it has a high dielectric constant of 7000 or more at a temperature range of 50.degree. to 70.degree. C. which permits normal operations of IC, and a decrease rate of dielectric constant of below 10% at DC bias of 1 V/.mu.m. Accordingly, the ceramic composition of the invention can be applied for the development of a laminated ceramic condenser for bypass of computer module IC.Type: GrantFiled: August 13, 1997Date of Patent: February 2, 1999Assignee: Korea Advanced Institute of Science and TechnologyInventors: Ho-Gi Kim, Yung Park, Yong-Joon Park
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Patent number: 5858901Abstract: Barium titanate temperature stable dielectric compositions are disclosed containing magnesium oxide, silicon dioxide, germanium oxide and optionally an oxide or carbonate of barium, calcium or strontium which can be used to produce multilayer ceramic capacitors with nickel or nickel alloy electrode that have a variation of capacitance with temperature of less than .+-.10% over the range -55.degree. C. to +125.degree. C. compared with the value of the capacitance at 25.degree. C., or to produce multilayer ceramic capacitors with noble metal inner electrodes that have a variation of capacitance with temperature of less than .+-.15% over the range 55.degree. to +125.degree. C. compared with the value at 25.degree. C., and which does not contain any second phases after sintering.Type: GrantFiled: February 21, 1996Date of Patent: January 12, 1999Assignee: Cookson Group plcInventors: Mike Ssu Hai Chu, John Bultitude, Christopher Hood, Kay Louise Nimmo, Michael Rand
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Patent number: 5827792Abstract: A dielectric ceramic composition mainly comprises a major component which comprises barium, titanium, neodymium, samarium and oxygen and is represented by the following compositional formula:xBaO-yTiO.sub.2 -zNd.sub.2 O.sub.3 -tSm.sub.2 O.sub.3wherein 0.1.ltoreq.x.ltoreq.0.2; 0.5.ltoreq.y.ltoreq.0.8; 0.01.ltoreq.z.ltoreq.0.2; 0.ltoreq.t.ltoreq.0.2, provided that x+y+z+t=1); and a minor component mainly comprising glass powder having a softening point of about 100.degree. to about 500.degree. C., which mainly comprises PbO, ZnO and B.sub.2 O.sub.3, and GeO.sub.2, and wherein the content (a) (% by weight) of the glass powder falls within the range of 1.ltoreq.a.ltoreq.25 and the content (b) (% by weight) of GeO.sub.2 falls within the range of 0.5.ltoreq.b.ltoreq.10, on the basis of the weight of the major component. The major component may further comprise Bi.sub.2 O.sub.3 and the composition may comprise bismuth as a minor component.Type: GrantFiled: August 29, 1995Date of Patent: October 27, 1998Assignee: UBE Industries, Ltd.Inventors: Koichi Fukuda, Masataka Fujinaga, Atsuyuki Mitani, Masatoshi Takeda, Shinichi Ishitobi
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Patent number: 5824616Abstract: The invention provides a dielectric ceramic composition represented by Formula 1:(1-x)Re.sub.1+a (A.sub.2/3 Nb.sub.1/3)O.sub.3+1.5a -xB.sub.1+b TiO.sub.3+bFormula 1wherein Re represents a component comprising a rare earth element, A represents a component comprising at least one element selected from the group consisting of Mg and Zn, B represents a component comprising Ca, x represents a number in the range of 0.40 to 0.80, a represents a number in the range of 0 to 0.15, and b represents a number in the range of 0 to 0.08. The composition has a high relative permittivity, a Q value and a small resonant frequency temperature coefficient. The composition is useful in miniaturizing dielectric resonators.Type: GrantFiled: February 22, 1996Date of Patent: October 20, 1998Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Hiroshi Kagata, Junichi Kato, Keiji Nishimoto
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Patent number: 5801111Abstract: Disclosed herein is a dielectric ceramics composition which comprises 100 moles of a primary component being a barium titanate (containing less than about 0.02 wt % of alkali metal oxide as an impurity) as expressed by the compositional formula:(1-.alpha.-.beta.-.gamma.){BaO}.sub.m.TiO.sub.2 +.alpha.M.sub.2 O.sub.3 +.beta.Re.sub.2 O.sub.3 +.gamma.(Mn.sub.1-x-y Ni.sub.x Co.sub.y)O(where M.sub.2 O.sub.3 denotes Sc.sub.2 O.sub.3 or Y.sub.2 O.sub.3 or both, Re.sub.2 O.sub.3 denotes Sm.sub.2 O.sub.3 or Eu.sub.2 O.sub.3 or both, 0.0025.ltoreq..alpha.+.beta..ltoreq.0.025, 0<.beta..ltoreq.0.0075, 0.0025.ltoreq..gamma..ltoreq.0.05, .gamma./(.alpha.+.beta.).ltoreq.4, 0.ltoreq.x<1.0, 0.ltoreq.y<1.0, 0.ltoreq.x+y<1.0, and 1.0000<m.ltoreq.1.035; from about 0.5-5 moles of MgO; and, about 0.2-3 pbw per 100 pbw of primary component and MgO, said auxiliary component being an oxide represented by Li.sub.2 O--(Si,Ti)O.sub.2 --Al.sub.2 O.sub.3 --ZrO.sub.2.Type: GrantFiled: January 21, 1997Date of Patent: September 1, 1998Assignee: Murata Manufacturing Co., Ltd.Inventors: Hiroyuki Wada, Harunobu Sano, Norihiko Sakamoto, Yukio Hamaji
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Patent number: 5780375Abstract: The invention is directed to a capacitor dielectric thick film composition comprising, by weight %: (1) 32-98% BaTiO.sub.3, (2) 2-60% zinc barium borate and (3) 0-8% Bi.sub.2 O.sub.3.Type: GrantFiled: June 28, 1996Date of Patent: July 14, 1998Assignee: E. I. du Pont de Nemours and CompanyInventor: Lorri Potvin Drozdyk
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Patent number: 5759935Abstract: Powders of BaCO.sub.3, TiO.sub.2, ZnO, etc. are mixed to each other at a predetermined ratio of quantity, calcined in an atmospheric air at 90.degree.-120.degree. C., and pulverized to obtain a calcined powder having an average grain size from 1 to 3 .mu. m. 0.1 to 20 parts-by weight of a powder having an average grain size from 0.1 to 1.5 .mu.m comprising a glass having a transition point of not higher than 450.degree. C. obtained by mixing powders of Pb.sub.3 O.sub.4, SiO.sub.2, Na.sub.2 O, etc. to each other, melting and then pouring into water and pulverizing the thus obtained glass is admixed to the calcined powder. The mixture is dried, pelleted by adding a resin and the pellet powder is molded into a cylindrical shape, applied with CIP (Cold isotactic press), and the molding product after the treatment is sintered in an atmospheric air at 850.degree. to 1000.degree. C. to obtain a dielectric ceramic sintered at low temperature.Type: GrantFiled: March 14, 1996Date of Patent: June 2, 1998Assignee: NGK Spark Co., Ltd.Inventors: Hidetoshi Mizutani, Masahiko Okuyama, Noritaka Yoshida, Hirofumi Ozeki, Hiroshi Katagiri
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Patent number: 5750452Abstract: The present invention relates to a dielectric ceramic composition for microwave which consists of BaO, Sm.sub.2 O.sub.3, TiO.sub.2 and PbO, and has a compositional formula of x(Ba.sub.1-.alpha., Pb.sub..alpha.)O-- ySm.sub.2 O.sub.3 -zTiO.sub.2, wherein 6 mol % .ltoreq.x.ltoreq.20 mol %, 6 mol %.ltoreq.y.ltoreq.20 mol %, 60 mol %.ltoreq.z.ltoreq.75 mol % and 0 mol % .ltoreq..alpha..ltoreq.0.2 mol %. Accordingly, since the dielectric ceramic composition for microwave according to the present invention has the dielectric constant more than 85, the temperature factor of the resonant frequency within .+-.5 ppm/.degree.C., and the quality factor more than 6000 in 1 GHz, it can be utilized in the filter for microwave, the dielectric for the resonator, the laminated ceramic capacitor, the dielectric for the filter for electromagnetic wave obstacle and the dielectric for capacitor.Type: GrantFiled: March 3, 1997Date of Patent: May 12, 1998Assignees: Korea Telecommunication Authority, Electronics And Telecommunications Research InstituteInventors: Jung-Rae Park, Tae-Hong Kim, Suk-Jin Lee, Tae-Goo Choy
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Patent number: 5744015Abstract: An electrochemical process for producing unsaturated hydrocarbon compounds from unsaturated hydrocarbon compounds and for extracting oxygen from a gas containing N.sub.2 O, NO, NO.sub.2, SO.sub.2, or SO.sub.3 is described. The process is characterized by the use of mixed metal oxide materials having a perovskite structure represented by the formula:A.sub.s A'.sub.t B.sub.u B'.sub.v B".sub.w O.sub.xwherein A represents a lanthanide or Y, or a mixture thereof; A' represents an alkaline earth metal or a mixture thereof; B represents Fe; B' represents Cr or Ti, or a mixture thereof; and B" represents Mn, Co, V, Ni, or Cu, or a mixture thereof.Type: GrantFiled: June 7, 1995Date of Patent: April 28, 1998Inventors: Terry J. Mazanec, Thomas L. Cable, John G. Frye, Jr., Wayne R. Kliewer
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Patent number: 5731220Abstract: A semiconductor device and process for making the same are disclosed which incorporate a relatively large percentage of erbium dopant (1 to 5%) into a BST dielectric film 24 with small grain size (e.g. 10 nm to 50 nm). Dielectric film 24 is preferably disposed between electrodes 18 and 26 (which preferably have a Pt layer contacting the BST) to form a capacitive structure with a relatively high dielectric constant and relatively low leakage current. Apparently, properties of the thin film deposition and small grain size. including temperatures well below bulk BST sintering temperatures, allow the film to support markedly higher defect concentrations without erbium precipitation than are observed for bulk BST. For erbium doping levels generally between 1% and 3%, over an order of magnitude decrease in leakage current (compared to undoped BST) may be achieved for such films.Type: GrantFiled: June 7, 1995Date of Patent: March 24, 1998Assignee: Texas Instruments IncorporatedInventors: Robert Tsu, Bernard M. Kulwicki