Patents by Inventor Yutaka Wada

Yutaka Wada has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20060110566
    Abstract: Disclosed is to provide with an optical recording medium of a write-once type in which an excellent recording characteristic can be obtained over low speed recording to high speed recording.
    Type: Application
    Filed: October 24, 2005
    Publication date: May 25, 2006
    Inventors: Yutaka Wada, Masatsugu Suwabe, Junko Shimada, Toru Yano, Keiji Oya, Koichi Shigeno
  • Publication number: 20060105679
    Abstract: A substrate polishing apparatus is used to polish a surface of a substrate such as a semiconductor wafer to a flat mirror finish. The substrate polishing apparatus has a polishing table and a polishing pad mounted on the polishing table for polishing a semiconductor substrate. The polishing pad has a through hole formed therein. The substrate polishing apparatus also has a light emission and reception device for emitting measurement light through the through hole formed in the polishing pad to the semiconductor substrate and receiving reflected light from the semiconductor substrate so as to measure a film on the semiconductor substrate. The light emission and reception device is disposed in the polishing table. The substrate polishing apparatus includes a supply passage for supplying a fluid to a path of the measurement light. The supply passage has an outlet portion detachably mounted on the polishing table.
    Type: Application
    Filed: November 16, 2005
    Publication date: May 18, 2006
    Inventors: Kazuto Hirokawa, Shunsuke Nakai, Shinrou Ohta, Yutaka Wada, Yoichi Kobayashi
  • Patent number: 6942548
    Abstract: An abrading plate has a self-stopping capability such that when an object, such as a semiconductor wafer having a device structure that includes raised regions and depressed regions fabricated on the surface, is being polished, the raised regions are removed and polishing stops automatically. The abrading plate, to produce a flat and mirror polished surface on the an object, has abrasive particles having a chemical purity of not less than 90% and a particle size of not more than two micrometers, a binder material, and a given volume of porosity. A ratio of the abrasive particles and the binder material is not less than 1:0.5 by volume, and proportions of abrasive particles, a binder material and porosity are, respectively, not less than 10%, not more than 60% and 10-40% by volume. A surface is polished for a given duration with a liquid not containing abrasive particles so as to eliminate the raised regions and to obtain a flat surface.
    Type: Grant
    Filed: July 30, 2001
    Date of Patent: September 13, 2005
    Assignee: Ebara Corporation
    Inventors: Yutaka Wada, Hirokuni Hiyama, Kazuto Hirokawa, Hisanori Matsuo
  • Publication number: 20050155868
    Abstract: An electrolytic processing apparatus can increase the efficiency of the dissociation reaction of water and efficiently perform electrolytic processing, and can eliminate the need for an operation for a change of ion exchanger. The electrolytic processing apparatus includes: a processing electrode and a feeding electrode; a liquid supply section for supplying a liquid containing an ion-exchange material between the workpiece and at least one of the processing electrode and the feeding electrode; a power source for applying a voltage between the processing electrode and the feeding electrode; and a drive section for moving the workpiece and at least one of the processing electrode and the feeding electrode relative to each other; wherein electrolytic processing of the workpiece is carried out while keeping the workpiece not in contact with and close to the processing electrode at a distance of not more than 10 ?m.
    Type: Application
    Filed: January 14, 2005
    Publication date: July 21, 2005
    Inventors: Itsuki Kobata, Yutaka Wada, Hirokuni Hiyama, Takayuki Saito, Yasushi Toma, Tsukuru Suzuki, Akira Kodera
  • Publication number: 20050094548
    Abstract: An optical recording medium comprises a transmission substrate and a recording layer formed on the transmission substrate, the recording layer containing at least a dye material expressed by a general formula shown at the following chemical formula (in the chemical formula 1, R1 represents alkyl group having carbon numbers 1 to 4, R2, R3 represent alkyl group having carbon numbers 1 to 4, benzyl group or groups combined to form 3 to 6 rings, Y1 and Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6) and a dye material expressed by a general formula represented by the following chemical formula 2(in the chemical formula 2, R1 and R2 represent alkyl groups having carbon numbers 1 to 4, benzyl groups or groups combined to form 3 to 6 rings, Y1, Y2 independently represent organic groups and X represent ClO4, BF4, PF6, SbF6): In a write once type optical recording medium such as DVD?R and DVD+R, satisfactory recording characteristics can be obtained from low-speed recording to high-s
    Type: Application
    Filed: October 27, 2004
    Publication date: May 5, 2005
    Applicants: Sony Corporation, ASAHI DENKA CO., LTD.
    Inventors: Yutaka Wada, Masatsugu Suwabe, Toshihiro Akimori, Junko Shimada, Keiji Oya, Koichi Shigeno, Toru Yano
  • Publication number: 20050054267
    Abstract: A wafer is pressed against a fixed abrasive and brought into sliding contact with the fixed abrasive. Thus, the wafer is polished. A surface of the fixed abrasive is dressed so as to generate free abrasive particles thereon. A liquid or a gas, composed of a mixture of liquid or inert gas and pure water or chemical liquid, is ejected onto the surface of the fixed abrasive during or after the dressing process.
    Type: Application
    Filed: October 6, 2004
    Publication date: March 10, 2005
    Inventors: Yutaka Wada, Tomohiko Akatsuka, Tatsuya Sasaki
  • Publication number: 20050030838
    Abstract: A magneto-optical recording medium for MSR reproduction of a high signal quality wherein both faces of a land and a groove are used as recording tracks is disclosed. A magneto-optical recording medium wherein both of a land portion and a groove portion on a substrate are used as recording and reproduction tracks while laser light having passed through an objective lens is illuminated on the recording and reproduction tracks is configured that a ratio Wg/Wl between a track width (Wg) of the groove portion and a track width (Wl) of the land portion is equal to or higher than 0.65 but equal to or lower than 0.85, and, where the wavelength of the laser light is represented by ?, the numerical aperture of the objective lens by NA and the refractive index of the substrate by n, the groove distance Gp is equal to or greater than 1.0×?/NA but equal to or smaller than 1.2×?/NA and besides the depth D of the groove is equal to or greater than ?/11 n but equal to or smaller than ?/8 n.
    Type: Application
    Filed: October 1, 2002
    Publication date: February 10, 2005
    Inventors: Yutaka Wada, Hiroshi Nakayama, Atsushi Takeuchi, Mitsuo Arima
  • Publication number: 20050022908
    Abstract: It is an object of the present invention to provide a metal surface treatment composition and a metal surface treatment method superior in stability, which can apply a good chemical conversion treatment to a galvanized steel plate without requiring a burden of waste water treatment, and a galvanized steel plate superior in a rust-preventive property and adhesion, which is obtained by such a metal surface treatment method. A metal surface treatment composition comprising niobium oxide colloidal particles, wherein the niobium oxide colloidal particles are derived from a niobium oxide sol which is stabilized by containing citric acid or salts thereof in an amount of 0.02 to 1.0 by a mole ratio relative to Nb.
    Type: Application
    Filed: July 16, 2004
    Publication date: February 3, 2005
    Inventors: Atsuhiko Tounaka, Yutaka Wada
  • Publication number: 20040248415
    Abstract: The present invention relates to a polishing method and a polishing liquid for polishing a workpiece such as a semiconductor wafer with a fixed abrasive. In the polishing method for polishing a workpiece by pressing the workpiece to be polished against a fixed abrasive and bringing the workpiece in sliding contact with the fixed abrasive, the workpiece is polished while supplying a polishing liquid which contains an anionic surface-active agent and does not contain abrasive particles.
    Type: Application
    Filed: July 8, 2004
    Publication date: December 9, 2004
    Inventors: Yutaka Wada, Tomohiko Akatsuka, Tatsuya Sasaki, Toshiya Hagihara
  • Patent number: 6827633
    Abstract: A wafer is pressed against a fixed abrasive and brought into sliding contact with the fixed abrasive. Thus, the wafer is polished. A surface of the fixed abrasive is dressed so as to generate free abrasive particles thereon. A liquid or a gas, composed of a mixture of liquid or inert gas and pure water or chemical liquid, is ejected onto the surface of the fixed abrasive during or after the dressing process.
    Type: Grant
    Filed: December 30, 2002
    Date of Patent: December 7, 2004
    Assignee: Ebara Corporation
    Inventors: Yutaka Wada, Tomohiko Akatsuka, Tatsuya Sasaki
  • Publication number: 20040242121
    Abstract: A substrate polishing apparatus polishes a surface of a substrate such as a semiconductor wafer to a flat mirror finish. The substrate polishing apparatus according to the present invention has a rotatable table having a polishing pad for polishing a semiconductor substrate, a light emission and reception device for emitting measurement light through a through hole formed in the polishing pad to the semiconductor substrate and receiving reflected light from the semiconductor substrate so as to measure a film on the semiconductor substrate, and a supply passage for supplying a fluid to a path of the measurement light. The supply passage has an outlet portion positioned in the through hole.
    Type: Application
    Filed: July 14, 2003
    Publication date: December 2, 2004
    Inventors: Kazuto Hirokawa, Shunsuke Nakai, Shinro Ohta, Yutaka Wada, Yoichi Kobayashi
  • Publication number: 20040235301
    Abstract: The present invention relates to a polishing method for polishing a workpiece by pressing the workpiece to be polished against a fixed abrasive and bringing the workpiece in sliding contact with the fixed abrasive. The polishing method includes a first step of polishing the workpiece while supplying a polishing liquid which contains an anionic surface-active agent and does not contain abrasive particles, and a second step of polishing the workpiece while supplying a polishing liquid which contains a cationic surface-active agent and does not contain abrasive particles.
    Type: Application
    Filed: January 30, 2004
    Publication date: November 25, 2004
    Inventors: Yutaka Wada, Tomohiko Akatsuka, Tatsuya Sasaki
  • Publication number: 20040221874
    Abstract: A method is suitable for cleaning substrates, after polishing, that require a high degree of cleanliness, such as semiconductor wafers, glass substrates, or liquid crystal displays. The method includes polishing a substrate using an abrasive liquid containing abrasive particles, and cleaning a polished surface of the substrate by supplying a cleaning liquid having substantially the same pH as the abrasive liquid or similar pH to the abrasive liquid so that a pH of the abrasive liquid attached to the polished surface of the substrate is not rapidly changed.
    Type: Application
    Filed: May 13, 2004
    Publication date: November 11, 2004
    Inventors: Yutaka Wada, Hirokuni Hiyama, Norio Kimura
  • Publication number: 20040180238
    Abstract: A first dielectric layer 3, a multilayer magnetic film 10 in which a first magnetic layer 4 having perpendicular magnetic anisotropy at room temperature, a second magnetic layer 5 having inplane magnetic anisotropy at room temperature, and a third magnetic layer 6 having perpendicular magnetic anisotropy at room temperature are sequentially laminated, a second dielectric layer 7, a reflective layer 8, and a protective layer 9 are sequentially laminated onto one principal plane of a disk substrate 2 on which a land and a groove exist, thereby forming a magnetooptic disk 1. Saturation magnetization of the second magnetic layer 5 is set to a range from 8.80×10−2 to 1.76×10−1 Wb/m2. A gas pressure upon film creation of the second magnetic layer is set to a range from 0.6 to 3.0 Pa. A content ratio of Co in the third magnetic layer 6 is set to a range from 15 to 17 atom %.
    Type: Application
    Filed: December 29, 2003
    Publication date: September 16, 2004
    Inventors: Yutaka Wada, Hiroshi Nakayama
  • Patent number: 6752692
    Abstract: A method is suitable for cleaning substrates, after polishing, that require a high degree of cleanliness, such as semiconductor wafers, glass substrates, or liquid crystal displays. The method includes polishing a substrate using an abrasive liquid containing abrasive particles, and cleaning a polished surface of the substrate by supplying a cleaning liquid having substantially the same pH as the abrasive liquid or similar pH to the abrasive liquid so that a pH of the abrasive liquid attached to the polished surface of the substrate is not rapidly changed.
    Type: Grant
    Filed: August 21, 2001
    Date of Patent: June 22, 2004
    Assignee: Ebara Corporation
    Inventors: Yutaka Wada, Hirokuni Hiyama, Norio Kimura
  • Patent number: 6712678
    Abstract: It is an object of the present invention to provide a mechanism for effectively discharging debris produced when a substrate is polished by a bonded-abrasive element, and a polishing apparatus. According to the present invention, a polishing apparatus presses a surface of a substrate against a bonded-abrasive surface and moves the surface to be polished and the bonded-abrasive surface relative to each other to polish the surface. A mechanism is provided for discharging debris produced on the bonded-abrasive surface when the surface to be polished is polished.
    Type: Grant
    Filed: September 21, 2001
    Date of Patent: March 30, 2004
    Assignee: Ebara Corporation
    Inventors: Yutaka Wada, Hirokuni Hiyama, Kazuto Hirokawa, Hisanori Matsuo
  • Patent number: 6672945
    Abstract: A abstract polishing apparatus has a substrate carrier a substrate and an abrasive member having a polishing surface. The surface is slidingly engaged with the substrate in order to effect polishing. The dressing device includes a light source when generating light rays for irradiating the polishing surface of the abrasive member, whereby dressing the polishing surface. A temperature control system control the temperature of the polishing surface of the abrasive member by sensing the temperature of the polishing surface with the temperature sensor. Mechanical dressing of the polishing surface, in addition to dressing by radiation of the polishing surface, may also be employed in order to flatten the entire polishing surface. The abrasive member preferably includes an abrasive particles, a binder and a photophilic for promoting the dressing of the polishing surface by light rays.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: January 6, 2004
    Assignee: Ebara Corporation
    Inventors: Hisanori Matsuo, Hirokuni Hiyama, Yutaka Wada, Kazuto Hirokawa
  • Patent number: 6626739
    Abstract: A method is provided for polishing a device wafer, which has projections and depressions formed on a surface thereof, with the use of an abrading plate. The method comprises polishing the device wafer while supplying a surface active agent and/or while dressing a surface of the abrading plate. This method for polishing the device wafer can always exhibit a self-stop function, without being restricted by the composition of the abrading plate, and without being restricted by the type of the substrate.
    Type: Grant
    Filed: August 18, 2000
    Date of Patent: September 30, 2003
    Assignee: Ebara Corporation
    Inventors: Yutaka Wada, Hirokuni Hiyama, Kazuto Hirokawa, Hisanori Matsuo
  • Patent number: 6595831
    Abstract: A polishing method and apparatus can concurrently establish a stable removal rate, a small step height reduction rate, and reduction of detects on the polished surface for various kinds of polished subjects, while providing less environmental problems and requiring less processing costs. The method for polishing a surface of a semiconductor device wafer comprises first polishing a surface of the semiconductor wafer by a first fixed abrasive polishing method; and finish polishing the polished surface of the semiconductor wafer by a second fixed abrasive polishing method different from the first fixed abrasive polishing method.
    Type: Grant
    Filed: April 28, 2000
    Date of Patent: July 22, 2003
    Assignee: Ebara Corporation
    Inventors: Kazuto Hirokawa, Hirokuni Hiyama, Yutaka Wada, Hisanori Matsuo, Noburu Shimizu
  • Patent number: RE39262
    Abstract: A polishing apparatus includes a turntable with an abrasive cloth mounted on an upper surface thereof, and a top ring disposed above the turntable for supporting a workpiece to be polished and pressing the workpiece against the abrasive cloth under a predetermined pressure. The turntable and the top ring are movable relatively to each other to polish a surface of the workpiece supported by the top ring with the abrasive cloth. The abrasive cloth has a projecting region on a surface thereof for more intensive contact with the workpiece than other surface regions of the abrasive cloth. The projecting region has a smaller dimension in a radial direction of the turntable than a diameter of the workpiece when the projecting region is held in contact with the workpiece. A position of the projection region is determined on the basis of an area in which the projecting region acts on the workpiece.
    Type: Grant
    Filed: February 28, 2002
    Date of Patent: September 5, 2006
    Assignee: Ebara Corporation
    Inventors: Masayoshi Hirose, Yoshimi Sasaki, Akira Ogata, Seiji Ishikawa, Tamami Takahashi, Hirokuni Hiyama, Yutaka Wada