Patents Assigned to Toshiba Ceramics Co., Ltd.
  • Patent number: 6054373
    Abstract: A method of removing metallic impurities diffused in a semiconductor substrate, comprising, the semiconductor-substrate-heating step of heating a semiconductor substrate to at least 200.degree. C. or higher and promoting the release and rediffusion of metallic impurities diffused in the semiconductor substrate, and the metallic-impurity-removing step of dissolving the metallic impurities arrived at the surface of the semiconductor substrate with a chemical agent and removing them from the substrate.
    Type: Grant
    Filed: January 14, 1998
    Date of Patent: April 25, 2000
    Assignees: Kabushiki Kaisha Toshiba, Purex Co., Ltd., Toshiba Ceramics Co., Ltd.
    Inventors: Hiroshi Tomita, Hisashi Muraoka, Ryuji Takeda
  • Patent number: 6043468
    Abstract: A carbon heater comprising heater members (11, 111, 121 . . . 161, 212, 222, 315, 325 . . . 345, 411, 515, 612) in which a plurality of carbon fiber bundles having a plurality of carbon fibers whose diameter is 5 to 15 .mu.m bundled are woven into a longitudinally elongated shape such as a wire shape or a tape shape and the impurity content is less than 10 ppm in ashes.
    Type: Grant
    Filed: July 31, 1998
    Date of Patent: March 28, 2000
    Assignees: Toshiba Ceramics Co., Ltd., Tokyo Electron Limited
    Inventors: Eiichi Toya, Masahiko Ichishima, Tomio Konn, Tomohiro Nagata, Shigeru Yamamura, Norihiko Saito, Kouji Teraoka, Takeshi Inaba, Hiroyuki Honma, Ken Nakao, Takanori Saito, Hisaei Osanai, Toshiyuki Makiya
  • Patent number: 6025596
    Abstract: In a measurement method for measuring the epitaxial film thickness of a multilayer epitaxial wafer, a reflectivity spectrum of a multilayer epitaxial wafer having at least two epitaxial layers of different electric characteristics is measured by using infrared radiation in a far infrared region of at least 500 cm.sup.-1 or less, and frequency-analysis is performed on the reflection spectrum thus obtained by a maximum entropy method, and the film thickness of each epitaxial layer is calculated on the basis of the analysis spectrum thus obtained.
    Type: Grant
    Filed: February 5, 1998
    Date of Patent: February 15, 2000
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Hiroshi Shirai, Kenji Akai, Toshio Abe, Chikara Tojima, Katsuyuki Iwata
  • Patent number: 6019837
    Abstract: A temperature sensor 42 is provided in a furnace 11, measuring temperature above a molten liquid 24 put in a crucible 12 to check proceedings of evaporation of oxygen vaporized from a free surface 44 of the molten liquid 24. From the data, and considering the relation with the oxygen dissolved into the crucible 12, the oxygen concentration in the molten liquid 24 can be found and the amount of oxygen taken into a single silicon crystal 40 pulled up from the molten liquid 24 can be figured out.
    Type: Grant
    Filed: November 25, 1997
    Date of Patent: February 1, 2000
    Assignees: Komatsu Electronic Metals Co., Ltd., Mitsubishi Materials Silicon Corporation, Kagaku Gijutsu Sinkou Jigyo Dan, Toshiba Ceramics Co., Ltd.
    Inventors: Susumu Maeda, Keisei Abe, Kazutaka Terashima, Hideo Nakanishi
  • Patent number: 6004393
    Abstract: A temperature sensor 42 is provided in a furnace 11, measuring temperature above a molten liquid 24 put in a crucible 12 to check proceedings of evaporation of oxygen vaporized from a free surface 44 of the molten liquid 24. From the data, and considering the relation with the oxygen dissolved into the crucible 12, the oxygen concentration in the molten liquid 24 can be found and the amount of oxygen taken into a single silicon crystal 40 pulled up from the molten liquid 24 can be figured out.
    Type: Grant
    Filed: January 22, 1999
    Date of Patent: December 21, 1999
    Assignees: Komatsu Electronic Metals Co., Ltd., Mitsubishi Materials Silicon Corporation, Kagaku Gijutsu Sinkou Jigyo Dan, Toshiba Ceramics Co., Ltd.
    Inventors: Susumu Maeda, Keisei Abe, Kazutaka Terashima, Hideo Nakanishi
  • Patent number: 6001470
    Abstract: A calcining tool material, comprising a flame-spray zirconia coating layer made of unstabilized zirconia and stabilized or partially-stabilized zirconia in admixture, formed on the surface of an alumina-silica-based substrate having an Al.sub.2 O.sub.3 content of not less than 65% by weight.
    Type: Grant
    Filed: November 26, 1997
    Date of Patent: December 14, 1999
    Assignee: Toshiba Ceramics Co., Ltd,
    Inventors: Shigeki Niwa, Tadashi Kimura, Hiroshi Okada, Toshiyuki Suzuki, Kenithi Urathuji, Ataru Nishikawa, Mamoru Uemura
  • Patent number: 5992711
    Abstract: An integrated submerged entry nozzle for thin slab continuous casting has a plate member 12 corresponding to the lower plate of a slide gate and a nozzle member 11 having a flat molten steel passage section in the part to be submerged into molten steel of at least the tip, the both 11. 12 being integrated together by the use of an organic adhesive. The plate member 12 and the nozzle member 11 are separately formed followed by baking or firing, the both 11, 12 are adhered together by the use of an organic adhesive, the adhesive is dried, the outside is covered with a shell, and refractory mortar is filled in the space. Thereafter, a refractory ring 28 is adhered in such a manner as to cover the inside of the adhesive joint part followed by drying.
    Type: Grant
    Filed: April 22, 1998
    Date of Patent: November 30, 1999
    Assignees: Toshiba Ceramics Co., Ltd., Sumitomo Metal Industries, Ltd.
    Inventors: Yoichiro Mochizuki, Tetsuro Fushimi, Etsuhiro Hasebe, Moriki Hashio, Toshihiko Murakami, Sei Hiraki
  • Patent number: 5972529
    Abstract: The present invention has been achieved by a material for a sintering appliance which comprises a base material comprising alumina.times.silica containing from 65 to 95% by weight of Al.sub.2 O.sub.3 having formed on the surface thereof a flame-coated film comprising ZrO.sub.2 and CaO as main components, wherein the content of CaO is from 23 to 30% by weight based on the weight of the ZrO.sub.2 and CaO, the mineral composition of the main components of the coated film is calcium zirconate. Preferably the difference of thermal expansion between the base material and the flame-coated film is 0.3 or more at 1,200.degree. C.
    Type: Grant
    Filed: April 17, 1998
    Date of Patent: October 26, 1999
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Tadashi Kimura, Hiroshi Okada, Toshiyuki Suzuki
  • Patent number: 5966625
    Abstract: A single crystal silicon wafer is sliced off so as to have a slant surface that is inclined from plane (001) such that the normal of the slant surface is inclined by 0.01.degree. to 0.2.degree. from direction [001] toward direction [110]. After being cleaned, the silicon wafer is heat-treated at 600-1,300.degree. C. for not less than 1 minute in an ultrapure argon or hydrogen atmosphere containing nitrogen at not more than 0.1 ppm, to thereby cause the slant surface to have a stepped crystal surface structure. The stepped crystal surface structure is constituted of step walls Sa and Sb when it has been formed by a heat treatment in an argon atmosphere, and substantially all of its step walls are of a type Sb when it has been formed by a heat treatment in a hydrogen atmosphere.
    Type: Grant
    Filed: November 6, 1998
    Date of Patent: October 12, 1999
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Lei Zhong, Norihiro Shimoi, Yoshio Kirino
  • Patent number: 5961874
    Abstract: In a flat casting nozzle 10 having a taper 13, the position of the terminal end 14 of the taper 13 formed on the long edge side and the position of the terminal end 17 of a taper 16 formed on the short edge side are mutually shifted.
    Type: Grant
    Filed: March 23, 1998
    Date of Patent: October 5, 1999
    Assignees: Toshiba Ceramics Co., Ltd., Sumitomo Metal Industries, Ltd.
    Inventors: Etsuhiro Hasebe, Tetsuro Fushimi, Tatsuya Shimoda, Yoichiro Mochizuki, Tadasu Takigawa, Toshihiko Murakami, Sei Hiraki
  • Patent number: 5958279
    Abstract: A refractory slide-gate plate including a refractory base plate which is designed in a ring shape or so as to have a recess portion on a surface thereof, a refractory plate member which is fixedly engaged with the inside of the ring-shaped refractory base plate or with the recess portion of the refractory slide-gate to be integrated with the refractory base plate, and an inert gas supply groove comprising a step portion which is formed in 2 to 20 mm width and in 2 to 20 depth on at least one of the inner peripheral portion of the ring-shaped refractory base plate and the inner peripheral portion of the recess portion. The refractory plate member is preferably formed of Al.sub.2 O.sub.3 --ZrO.sub.2 --C-based refractory material or ZrO.sub.2 -based refractory material.
    Type: Grant
    Filed: May 28, 1993
    Date of Patent: September 28, 1999
    Assignee: Toshiba Ceramics Co., Ltd
    Inventors: Toshio Kawamura, Kazuhide Kawai, Shigeki Niwa
  • Patent number: 5937316
    Abstract: The present invention is a SiC member and fabrication method thereof useful for heat treating semiconductors, wherein at least the surface of the member comprises: CVD-.beta.-phase SiC columnar crystals grown in perpendicular to the surface of the member; and CVD-.alpha.-phase SiC crystals grown up from interface of CVD-.beta.-phase columnar crystals. This structure thereby makes it possible to reduce the infrared ray transmittance of the heat treatment member and facilitates the heating of the heat treatment member by absorbing the infrared rays. Absorption of the IR rays results in favorable the temperature follow-up characteristics during the heat treatment of a semiconductor.
    Type: Grant
    Filed: June 20, 1997
    Date of Patent: August 10, 1999
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Takeshi Inaba, Syuichi Takeda, Masanori Sato
  • Patent number: 5904769
    Abstract: This invention provides an epitaxial growth method capable of decreasing variations of the resistance of an epitaxial layer resulting from an in-plane temperature distribution of a silicon wafer and also capable of reducing particles and haze. This epitaxial growth method is an epitaxial growth method of growing a boron- or phosphorus-doped silicon epitaxial layer on the surface of a silicon wafer with an in-plane temperature distribution of 2 to 50.degree. C., and includes the steps of arranging the silicon wafer in a reaction vessel, supplying into the reaction vessel a source gas containing (a) silane, (b) 5 to 600 vol % of hydrogen chloride added to the silane, and (c) a dopant consisting of a boron compound or a phosphorus compound, and growing a boron- or phosphorus-doped silicon epitaxial layer on the surface of the wafer by setting a vacuum degree of 10 to 200 torr in the reaction vessel and heating the wafer to 900 to 1100.degree. C.
    Type: Grant
    Filed: January 3, 1997
    Date of Patent: May 18, 1999
    Assignees: Toshiba Ceramics Co., Ltd., Toshiba Machine Co., Ltd.
    Inventors: Tadashi Ohashi, Shinichi Mitani, Takaaki Honda
  • Patent number: 5868850
    Abstract: A vapor phase growth unit for vapor phase growing on the surface of a wafer under a heated condition, which supports the wafer with a wafer supporter within a reaction chamber and has a heater under the wafer supported by said wafer supporter, wherein a reflection plate for reflecting at least downward heat from said heater is provided, an insulation cylinder is provided surrounding the side periphery of the heater, and the reflection plate consists of vitreous carbon.
    Type: Grant
    Filed: June 6, 1996
    Date of Patent: February 9, 1999
    Assignees: Toshiba Ceramics Co., Ltd., Toshiba Kikai Co., Ltd.
    Inventors: Masahiko Ichishima, Eiichi Toya, Tadashi Ohashi, Masaki Shimada, Shinichi Mitani, Takaaki Honda
  • Patent number: 5856251
    Abstract: Castable refractory for a slide gate plate is mainly formed of alumina raw material and amorphous carbon raw material of 2 to 15 wt %, and contains silicon carbide and/or boron carbide, the total content thereof being equal to 0.5 to 10 wt % (the content of boron carbide is equal to or less than 3 wt %, and when the content of boron carbide is less than 0.5 wt %, silicon carbide is set to 3 wt % or more), 2 to 10 wt % magnesia of 1 mm or less in particle size, 0.2 to 3 wt % silica fine powder of 5 micrometers or less in particle size, and 0.1 to 5 wt % salt of condensate of formalin and aromatic sulfonate.
    Type: Grant
    Filed: June 9, 1997
    Date of Patent: January 5, 1999
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Hisahiro Teranishi, Isao Imai, Toshihiro Indou
  • Patent number: 5849597
    Abstract: A treatment apparatus for analyzing the impurities in silicic material with high precision, includes a container having an inner space in which at least one analysis sample container and a sample decomposing solution are accommodated. The container is divided into a lid body and a lower body, each of the lid body and the lower body being opened at the division surface side thereof to form an open end and being closed at the surface side opposite to the division surface side to form a close end thereof. The inner peripheral surface of the open end of the lower body is formed in a stepwise shape so that the analysis sample container is disposed to be spaced from the surface of the decomposing solution which is stocked in the lower body, and the inner peripheral surfaces of the lid body and the lower body are smoothly continuously threadily engaged with each other through abutment faces thereof to keep the container in an appropriate hermetic level.
    Type: Grant
    Filed: December 18, 1996
    Date of Patent: December 15, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Fumio Tokuoka, Kazuhiko Shimanuki
  • Patent number: 5834108
    Abstract: A ceramic porous body has a layered structure including a plurality of foam-like ceramic layers. The foam-like ceramic layers are formed by firing foam-like ceramic shaped layers each having a thickness of not more than 5 mm. The adjacent shaped layers are joined directly, or bonded via a thin foam-like ceramic layer or dense ceramic layer.
    Type: Grant
    Filed: August 21, 1995
    Date of Patent: November 10, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shunzo Shimai, Koichi Imura, Ichiro Shibata, Kenichi Okamoto, Akiko Niizuma, Tadayoshi Muto
  • Patent number: 5817274
    Abstract: Disclosed is a method of manufacturing aluminum nitride, which comprises the steps of preparing a mixed gas consisting essentially of an ammonia gas and at least 0.5% by volume of a hydrocarbon gas, calcining .gamma.-Al.sub.2 O.sub.3 or a precursor thereof at 300.degree. to 1,100.degree. C. so as to prepare the .gamma.-Al.sub.2 O.sub.3 having a moisture content of 1 weight % or less; heating the calcined .gamma.-Al.sub.2 O.sub.3 in the mixed gas at a temperature of 1,200.degree. to 1,700.degree. C., thereby preparing porous aluminum nitride having a specific surface area of 10 m.sup.2 /g or more; and heat-treating the porous aluminum nitride in an atmosphere of an ammonia gas, or a mixed gas of an ammonia gas and an inert gas, at 1600.degree. to 2000.degree. C., so as to make contents of both carbon and oxygen contained in the aluminum nitride 1 weight % or less.
    Type: Grant
    Filed: September 4, 1997
    Date of Patent: October 6, 1998
    Assignees: Toshiba Ceramics Co., Ltd., Toshiba Monofrax Co., Ltd.
    Inventors: Hiroaki Kotaka, Hidenori Yamaoka, Shuitsu Matsuo, Masahiro Ando, Mikiya Fujii, Hiroyuki Terada, Yasuo Misu
  • Patent number: 5808745
    Abstract: A silicon wafer measuring method includes: (a) a first step of measuring a light transmission characteristic (I.sub.OBS) of the pulled silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the pulled silicon wafer, (b) a second step of measuring a light transmission characteristic (I.sub.O) of a floating zone silicon wafer functioning as a reference silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the floating zone silicon wafer, and (c) a third step of calculating a substitutional carbon concentration ?C.sub.SC ! on the basis of the light transmission characteristic (I.sub.OBS) of the pulled silicon wafer measured during the first step and the light transmission characteristic (I.sub.O) of the floating zone silicon wafer measured during the second step, (d) a fourth step of comparing the substitutional carbon concentration ?C.sub.
    Type: Grant
    Filed: May 6, 1997
    Date of Patent: September 15, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Hiroshi Shirai, Mikio Watanabe, Shinichiro Takasu
  • Patent number: 5804324
    Abstract: A setting member for a heating material formed by sintering and heating a base and a coating layer at 1300.degree. to 1550.degree. C., in which the base comprises at least one selected from the group consisting of Al.sub.2 O.sub.3, MgO and ZrO.sub.2 in an amount of 70 wt % or more, the coating layer contains at least one main component selected from the group consisting of Al.sub.2 O.sub.3, MgO and ZrO.sub.2 in an amount of 80 wt % or more and 0.5 to 10.0 wt % of at least one additional component selected from Fe.sub.2 O.sub.3, TiO.sub.2, BaO, SrO, ZrO.sub.2, CaO, and MgO (different from CaO and MgO used as a stabilizer for ZrO.sub.2) excluding the same types of the additional component as used in the main component of the coating layer.
    Type: Grant
    Filed: January 18, 1996
    Date of Patent: September 8, 1998
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Shigeki Niwa, Hiroshi Okada, Yasuharu Okiyama, Toshiyuki Suzuki