And Divalent Metal Oxide Other Than Alkaline Earth Oxide Or Magnesium Oxide Patents (Class 501/138)
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Patent number: 6376079Abstract: The present invention provides a semiconducting ceramic which possesses a dielectric strength of 800 V/mm or more and a specific resistance at room temperature of 100 &OHgr;·cm or less, the specific resistance at room temperature undergoing substantially no time-course change. The semiconducting ceramic is formed of a sintered semiconducting material containing barium titanate, wherein the average grain size of the semiconducting ceramic is about 1.0 &mgr;m or less and the relative spectral intensity ratio represented by BaCO3/BaO, which is determined by XPS at the surface of the ceramic, is 0.5 or less.Type: GrantFiled: March 30, 1999Date of Patent: April 23, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Mitsutoshi Kawamoto, Hideaki Niimi
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Patent number: 6376085Abstract: A joining material for an electronic component is disclosed. The component has a plurality of functional layers, each selected from a magnetic layer and dielectric layer and the functional layers are joined with each other. The joining material is comprises a glass and a composition of a mol % of ZnO, b mol % of BaO and c mol % of TiO2 (a=12-45, b=4-45, c=18-81, a+b+c=100), wherein 0.1 to 10 weight parts of the glass is added to 100 weight parts of the composition.Type: GrantFiled: February 24, 1999Date of Patent: April 23, 2002Assignee: NGK Insulators, Ltd.Inventors: Takeshi Oobuchi, Yasunori Koda
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Publication number: 20020036282Abstract: A perovskite compound of the formula, (Na½Bi½)1−xMx(Ti1−yM′y)O3±z, where M is one or more of Ca, Sr, Ba, Pb, Y, La, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu; and M′ is one or more of Zr, Hf, Sn, Ge, Mg, Zn, Al, Sc, Ga, Nb, Mo, Sb, Ta, W, Cr, Mn, Fe, Co and Ni, and 0.01<x<0.3, and 0.01<y<0.3, and z<0.1 functions as an electromechanically active material. The material may possess electrostrictive or piezoelectric characteristics.Type: ApplicationFiled: April 6, 2001Publication date: March 28, 2002Inventors: Yet-Ming Chiang, Sossity A. Sheets, Gregory W. Farrey, Nesbitt W. Hagood, Andrey Soukhojak, Haifeng Wang
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Patent number: 6359327Abstract: A monolithic electronic element is fabricated from a semiconducting ceramic, which element can be produced through firing at 1000° C. or lower and exhibits a satisfactory PTC characteristic even when the element is produced through reoxidation at low temperature. The monolithic electronic element 1 includes a sintered laminate 3 formed of alternatingly stacked semiconducting ceramic layers 5 and internal electrode layers 7, and external electrodes 9 formed on the sintered laminate, wherein the semiconducting ceramic layers 5 comprise sintered barium titanate containing boron oxide; an oxide of at least one metal selected from among barium, strontium, calcium, lead, yttrium and a rare earth element; the boron oxide being incorporated in an amount, as reduced to atomic boron (B), satisfying the following relationships: 0.001≦B/&bgr;≦0.50 and 0.5≦B/(&agr;−&bgr;)≦10.Type: GrantFiled: March 1, 2000Date of Patent: March 19, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Hideaki Niimi, Tatsuya Matsunaga
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Patent number: 6355097Abstract: Bis(dipivaloylmethanato)diisobutoxytitanium or bis(dipivaloylmethanato)-di(2,2 -dimethyl-1-propoxytitanium per se, or as used as a raw material in a MOCVD process, as is or as a solution in an organic solvent, for example, tetrahydrofuran, produces a dielectric thin film of a fine texture having a film thickness which is proportional to the deposition time and the concentration of the solution.Type: GrantFiled: May 16, 2001Date of Patent: March 12, 2002Assignee: Mitsubishi Materials CorporationInventors: Atsushi Itsuki, Taiji Tachibana, Hiroto Uchida, Katsumi Ogi
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Patent number: 6346497Abstract: A dielectric ceramic composition exhibiting a firing temperature of 1300° C. or less, a dielectric constant of 200 or more, a low loss under a high-frequency-high-voltage alternating current, high insulation resistance at high electric field strength, characteristics satisfying the B and X7R characteristics, and excellent high-temperature load properties. It contains a barium titanate solid solution and additive components, and is represented by the formula, ABO3+aR and bM, wherein ABO3 represents the barium titanate solid solution having a perovskite structure; R represents an oxide of at least one metal, M represents an oxide of at least one other metal, a and b respectively represent the molar ratios of single metal oxides and a sintering additive, wherein 0.950≦A/B (molar ratio)≦1.050, 0.12<a≦0.30, and 0.04≦b≦0.30.Type: GrantFiled: September 1, 1999Date of Patent: February 12, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Tomoyuki Nakamura, Shinobu Mizuno, Harunobu Sano
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Patent number: 6346496Abstract: 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: GrantFiled: July 23, 1999Date of Patent: February 12, 2002Assignee: Murata Manufacturing Co., Ltd.Inventors: Yasuhiro Nabika, Tetsukazu Okamoto, Toshiharu Hirota, Noriyuki Yamamoto
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Publication number: 20020016249Abstract: A ceramic capacitor containing at least one dielectric layer formed from a dielectric ceramic composition comprising a sintered body containing ceramic particles having a core/shell structure in an amount of 15% or more based on the total ceramic particles of the sintered body, the core/shell structured particle being composed of a core portion, which is BaTiO3 crystal, and a shell portion surrounding the core portion, which is made of a solid solution comprising BaTiO3 as a major component, has excellent temperature characteristics and a long life-time.Type: ApplicationFiled: June 29, 2001Publication date: February 7, 2002Inventors: Kenji Saito, Koichiro Morita, Youichi Mizuno, Yasunobu Kawamoto, Yoshikazu Okino, Noriyuki Kohzu, Hirokazu Chazono
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Publication number: 20020016246Abstract: 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.Type: ApplicationFiled: March 30, 2001Publication date: February 7, 2002Inventors: Jong Hee Kim, Shigehiro Fujino, Nobutake Hirai
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Patent number: 6344427Abstract: A dielectric ceramic composition of the present invention is a mixture of barium titanate as a main component whose Ba/Ti molar ratio ranging from 1.001 to 1.05 and sub components comprising, at least 0.5 to 5.0 mol of Mg in the form of MgO, 0.1 to 3.0 mol of Dy in the form of Dy2O3, 0.01 to 0.4 mol of Mn in the form of Mn3O4, 0.01 to 0.26 mol of V in the form of V2O5, 0.3 to 3.5 mol of Si in the form of SiO2 and 0.01 to 3.0 mol of Al in the form of Al2O3 per 100 mol of the barium titanate. Even when external electrodes are made of base metal such as copper or the like, a multilayer capacitor whose dielectric layers are not reduced and have high insulation resistance can be obtained by using the dielectric ceramic composition of the present invention.Type: GrantFiled: November 29, 2000Date of Patent: February 5, 2002Assignee: Matsushita Electric Industrial Co., Ltd.Inventors: Kazuhiro Komatsu, Atsuo Nagai, Keiji Kobayashi, Hideki Kuramitsu
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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: 6337032Abstract: A sol-gel precursor mixture for forming a perovskite ferroelectric material and a method for forming a ferroelectric material are provided. The precursor solution comprises a sol-gel formulation of a mixture of an inorganic salt of at least one metal, and metal-organic compounds of other constituent metals in a suitable pH controlled aqueous solvent mixture to form a stable, clear sol-gel mixture. The precursor solution and method provides for formation of thin layers of other ferroelectric dielectrics and piezoelectric materials, particularly lead containing materials, for application including non-volatile DRAMs, optoelectronic devices relying on non-linear optical properties, and piezoelectric devices, and is compatible with processing for submicron device structures for bipolar, CMOS or bipolar CMOS circuits.Type: GrantFiled: February 16, 2000Date of Patent: January 8, 2002Assignees: Nortel Networks Limited, Queen's UniversityInventors: Vasanta Chivukula, Michael Sayer, David R. McDonald, Ismail T. Emesh
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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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Publication number: 20010042852Abstract: The piezoelectric ceramic composition of the present invention contains, as a main component, a material having a composition represented by Formula: CaMXBi4−xTi4−X(Nb1−ATaA)XO15, where M is at least one element selected from the group consisting of Ca, Sr, and Ba; 0.0≦A≦1.0; and 0.0≦X≦0.6.Type: ApplicationFiled: February 26, 2001Publication date: November 22, 2001Inventors: Keiichi Takahashi, Masamitsu Nishida, Hiroshi Sogou
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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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Patent number: 6316376Abstract: A dielectric ceramic composition comprising 3BaO.5TiO2.3Nb2O5 (Ba3Ti5Nb6O28) as a main component and at least one selected from, as a minor component, (b-1) sintering auxiliary selected from the group consisting of a boron-containing glass compound, CuO, ZnO or mixtures thereof, or (b-2) additives selected from the group consisting of V2O5, SnO2, MgO, NiO, Sb2O3, Bi2O3, LiF, Ag2O or mixtures thereof, and mixtures of (b-1) and (b-2), and its preparation process are disclosed.Type: GrantFiled: January 22, 2001Date of Patent: November 13, 2001Inventors: Kug Sun Hong, Jung-Kun Lee, Dong-Wan Kim, Hyun-Seok Jung, Hee-Bum Hong, Jae-Yun Lee, Soung-Jun Yoon
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Patent number: 6309995Abstract: In a start powder mixture of magnesium zinc titanate and a barium lithium boro-silicate flux, it is discovered that the addition of lithium to the flux enables the manufacture of multilayer ceramic capacitors using the powder mixture, that perform to the COG standard including an accelerated life test. This addition of lithium also makes possible the sintering to maturity of COG multilayer capacitors at temperatures as low as 950° C., which in turn allows the use of silver-palladium alloy buried electrodes of high silver and low palladium content which in turn lead to higher capacitor Q and lower manufacturing costs.Type: GrantFiled: August 31, 2000Date of Patent: October 30, 2001Assignee: MRA Laboratories, Inc.Inventors: Galeb H. Maher, Samir G. Maher
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Patent number: 6304157Abstract: A high-frequency dielectric ceramic composition comprises Ba, Ti, Nd, Sm, and Pr as primary components represented by the formula xBaO-yTiO2-z{(1−m−n)Nd2O3-mSm2O3-nPr2O11/3} wherein coefficients x, y, z, m, and n represent molar ratios, x+y+z=1, 0<m≦0.40, 0<n≦0.25, and the coefficients x, y, and z are in an area bounded by points A, B, C and D in a ternary diagram, wherein point A is at (x=0.16, y=0.70, z=0.14), point B is at (x=0.16, y=0.68, z=0.16), point C is at (x=0.13, y=0.68, z=0.19), and point D is at (x=0.13, y=0.70, z=0.17); wherein the composition further comprises a Bi compound in an amount of more than 0 parts by weight to about 9 parts by weight on the basis of Bi2O3 and an Fe compound in an amount of more than 0 parts by weight to about 0.Type: GrantFiled: April 7, 2000Date of Patent: October 16, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Takaya Wada, Hiroshi Tamura
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Patent number: 6295196Abstract: A monolithic ceramic electronic component includes a laminate including a plurality of ceramic layers obtained by sintering a ceramic raw material powder, and a plurality of internal electrodes located between the ceramic layers and obtained by sintering a metallic powder. The ceramic layers have a thickness of about 3 &mgr;m or less and are composed of ceramic grains having an average particle diameter of more than about 0.5 &mgr;m, the particle diameter of the ceramic grains in the thickness direction of the ceramic layers is smaller than the thickness of the ceramic layers, and the internal electrodes have a thickness of about 0.2 to 0.7 &mgr;m.Type: GrantFiled: July 6, 2000Date of Patent: September 25, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Yukio Hamaji, Nobuyuki Wada, Tsuyoshi Yamana, Takanori Nakamura
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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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Publication number: 20010016552Abstract: A high rigidity glass-ceramic substrate for a magnetic information storage medium has a ratio of Young's modulus to specific gravity within a range from 37 to 63 and comprises Al2O3 within a range from 10% to less than 20%. A predominant crystal phase of the glass-ceramic substrate consists of one or more crystals selected from the group consisting of &bgr;-quartz, &bgr;-quartz solid solution, enstatite, enstatite solid solution, forsterite and forsterite solid solution.Type: ApplicationFiled: November 30, 1998Publication date: August 23, 2001Inventors: NAOYUKI GOTO, KOUSUKE NAKAJIMA, JUNKO ISHIOKA
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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: 20010008866Abstract: 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 18, 1998Publication date: July 19, 2001Inventors: MITSUTOSHI KAWAMOTO, HIDEAKI NIIMI, RYOUICHI URAHARA, YUKIO SAKABE
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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: 6258450Abstract: The dielectric ceramic composition is composed of a sintered body of ceramic particles containing Ba2Ti5O11 as a major component. The ceramic particles may contain Ag in the form of solid solution at the rate of 0.2% to 3.0% by mole. the ceramic particles may further contain Ba2TiSi2O8 so the BaTi5O11/Ba2TiSi2O8 ratio is 1.5 to 9 BaTi5O11 to 1 Ba2TiSi2O8. The dielectric ceramic composition can be sintered at a low enough temperature to enable a highly conductive metal such as Ag, Cu or the like to be burned and sintered integrally.Type: GrantFiled: July 21, 1999Date of Patent: July 10, 2001Assignee: Taiyo Yuden Co., Ltd.Inventors: Nobuhiro Sasaki, Yoshinao Takahashi, Katsuyuki Horie
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Publication number: 20010006928Abstract: A dielectric ceramic composition comprising as main components barium titanate and a component M (wherein M is at least one type of component selected from manganese oxide, iron oxide, cobalt oxide, and nickel oxide) and having a ferroelectric phase region, wherein the concentration of the component M in the ferroelectric phase region changes from the outside toward the center. The concentration of the component M in the ferroelectric phase region is higher at the outside compared with near the center of the ferroelectric phase region. It is possible to realize a multi-layer capacitor which can satisfy both of the X7R characteristic (EIA standard) and B characteristic (EIAJ standard) of the temperature characteristic of the electrostatic capacity, has little voltage dependency of the electrostatic capacity and the insulation resistance, is superior in insulation breakdown resistance, and can use Ni or a Ni alloy as the internal electrode layer.Type: ApplicationFiled: December 21, 2000Publication date: July 5, 2001Applicant: TDK CorporationInventor: Takeshi Masuda
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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: 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: 6187707Abstract: A barium titanate-based semiconductive ceramic composition for facilitating miniaturization of thermistor devices by improving rush current resistance characteristics is provided. In the barium titanate-based semiconductive ceramic composition, a fraction of the Ba in BaTiO3 as the major component is replaced with 1 to 25 mole percent of Ca, 1 to 30 mole percent of Sr, and 1 to 50 mole percent of Pb; and wherein to 100 mole percent of the major component, the semiconductivity-imparting agent is added in an amount of 0.2 to 1.0 mole percent as a converted element content, and the additive comprises manganese oxide in an amount of 0.01 to 0.10 mole percent as a converted Mn content, silica in an amount of 0.5 to 5 mole percent as a converted SiO2 content, and magnesium oxide in an amount of 0.028 to 0.093 mole percent as a converted Mg content.Type: GrantFiled: May 20, 1999Date of Patent: February 13, 2001Assignee: Murata Manufacturing Co., Ltd.Inventors: Satoshi Kakihara, Toshiharu Hirota, Yasuhiro Nabika, Noriyuki Yamamoto
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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: 6162752Abstract: The present invention provides barium titanate powder having a withstanding voltage of 800 V/mm or more and a specific resistance at room temperature of 100 .OMEGA..multidot.cm or less, the specific resistance at room temperature undergoing substantially no time-course change. Barium titanate of the powder of the present invention assumes a cubic crystal system. The powder has a particle size of about 0.1 .mu.m or less; the ratio represented by BaCO.sub.3 /BaO as obtained through XPS is about 0.42 or less; the lattice constant is about 0.4020 nm or more; and the ratio represented by Ba/Ti is about 0.988-0.995.Type: GrantFiled: May 11, 1999Date of Patent: December 19, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Mitsutoshi Kawamoto, Hideaki Niimi
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Patent number: 6153931Abstract: The present invention provides a barium titanate-based semiconducting ceramic which exhibits excellent PTC characteristic and which can be fired at a temperature lower than 1000.degree. C. The present invention also provides an electronic element fabricated from the ceramic. The semiconducting ceramic contains, in a semiconducting sintered barium titanate; boron oxide; an oxide of at least one of barium, strontium, calcium, lead, yttrium and a rare earth element; and an optional oxide of at least one of titanium, tin, zirconium, niobium, tungsten and antimony in which the atomic boron is0.005.ltoreq.B/.beta..ltoreq.0.50 and1.0.ltoreq.B/(.alpha.-.beta.).ltoreq.4.0wherein .alpha. represents the total number of atoms of barium, strontium, calcium, lead, yttrium and rare earth element contained in the semiconducting ceramic, and .beta. represents the total number of atoms of titanium, tin, zirconium, niobium, tungsten and antimony contained in the semiconducting ceramic.Type: GrantFiled: March 4, 1999Date of Patent: November 28, 2000Assignee: Murata Manufacturing Co., Ltd.Inventors: Hideaki Niimi, Mitsutoshi Kawamoto, Akinori Nakayama, Satoshi Ueno, Ryouichi Urahara
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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: 6074970Abstract: A multilayer ceramic capacitor is produced by using a dielectric ceramic composition prepared by allowing a composition represented by the composition formula (Ba.sub.1-x Ca.sub.x)TiO.sub.3 (provided that 0.005.ltoreq.x.ltoreq.0.05), namely, 0.5-5 mol % to contain an additive of MnO--CoO--MgO at 0.2 to 2 mol % and a Y.sub.2 O.sub.3 additive at 2.5 mol % or less and further adding a glass component comprising SiO.sub.2 --Al.sub.2 O.sub.3 --BaO--CaO--Ta.sub.2 O.sub.5 at 0.5 to 5 mol % to the resulting composition. The dielectric ceramic composition can be prepared into slurry well by using an aqueous binder and can be sintered well with no occurrence of any crack even by fast firing, and even after barrel treatment, additionally, chipping hardly occurs in the dielectric ceramic composition. Accordingly, the resulting multilayer ceramic capacitor exerts an excellent breakdown voltage even at a large size and can therefore satisfy the JIS B characteristic.Type: GrantFiled: December 11, 1998Date of Patent: June 13, 2000Assignees: Kabushiki Kaisha Toshiba, Nippon Chemi-Con CorporationInventors: Yohashi Yamashita, Hideyuki Kanai, Hironari Shoji, Yuichi Nakano
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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: 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: 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: 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: 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: 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: 5908802Abstract: A process for producing powders of perovskite-type compounds which comprises mixing a metal alkoxide solution with a lead acetate solution to form a homogeneous, clear metal solution, adding an oxalic acid/n-propanol solution to this metal solution to form an easily filterable, free-flowing precursor powder and then calcining this powder. This process provides fine perovskite-phase powders with ferroelectric properties which are particularly useful in a variety of electronic applications.Type: GrantFiled: October 30, 1997Date of Patent: June 1, 1999Assignee: Sandia CorporationInventors: James A. Voigt, Diana L. Sipola, Bruce A. Tuttle, Mark T. Anderson