Patents by Inventor Minoru Eguchi

Minoru Eguchi 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: 20030140843
    Abstract: The invention provides a method of producing silicon single crystals which comprises using the CZ method under application of a magnetic field to the silicon melt and under application of an electric current containing a component perpendicular to this magnetic field, namely using the EMCZ method, adjusting the pulling rate in the process of single crystal growth and thereby growing a single crystal under conditions such that the outside diameter of the potential region of the ring-forming oxidation-induced stacking faults (R-OSF) occurring in the cross section of the crystal is within the range of 70% to 0% of the crystal diameter. By this, wafers for semiconductors excellent in device characteristics such as gate oxide integrity or the like can be produced with high productivity without formation of COPs with not less than 0.1 &mgr;m in size, or of dislocation clusters.
    Type: Application
    Filed: November 8, 2002
    Publication date: July 31, 2003
    Inventors: Tadashi Kanda, Shunji Kuragaki, Masahito Watanabe, Minoru Eguchi
  • Patent number: 6579363
    Abstract: By using a semiconductor single crystal pulling apparatus for growing single crystals by the Czochralski method while rotating the melt by a magnetic field and electric current, namely by the EMCZ method, which comprises a main pulling means for pulling a single crystal, a holding mechanism for gripping an engaging stepped portion formed on the single crystal through engaging members and a sub pulling means for moving the holding mechanism up and down and in which an electric current is passed through the main pulling means and through the sub pulling means, it is possible to prevent heavy single crystals from undergoing a falling accident and, at the same time, effectively reduce the power consumption. In this pulling apparatus, it is effective to feed an electric current to the sub pulling means alone and it is desirable to dispose two or more electrodes whether the pulling means is of a shaft type or wire type.
    Type: Grant
    Filed: October 17, 2001
    Date of Patent: June 17, 2003
    Assignees: Sumitomo Metal Industries, Ltd., NEC Corporation
    Inventors: Souroku Kawanishi, Masahito Watanabe, Minoru Eguchi
  • Patent number: 6527852
    Abstract: A semiconductor crystal growing apparatus includes a device for applying a magnetic field to inside a semiconductor melt and a device for passing a current through the semiconductor melt. An electrode for applying the current to the inside of the semiconductor melt extends through a tube surrounding the electrode.
    Type: Grant
    Filed: April 18, 2001
    Date of Patent: March 4, 2003
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 6497761
    Abstract: An apparatus for growing a single crystal of semiconductor is provided, which makes it possible to grow a heavy single crystal of semiconductor of 100 kg or greater in weight even if a growing single crystal contains a neck. In the apparatus, the first and second electrodes are provided such that the first ends of the first and second electrodes are electrically connected to the power supply and the second ends of the first and second electrodes are contacted with the melt in the crucible. During the growth process, a specific voltage is applied across the first ends of the first and second electrodes, thereby forming the electrical current path interconnecting the second ends of the first and second electrodes in the melt. The magnetic field is generated with the magnetic field generator to intersect with the electrical current path in the melt. No electric current flows through the growing single crystal from the melt.
    Type: Grant
    Filed: March 6, 2001
    Date of Patent: December 24, 2002
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 6432198
    Abstract: In an apparatus for growing a semiconductor single crystal from semiconductor melt, a crucible retains the semiconductor melt. An electrode contacts with the semiconductor melt and applies current to the semiconductor melt. The electrode is formed of the same material as the semiconductor crystal.
    Type: Grant
    Filed: February 1, 2001
    Date of Patent: August 13, 2002
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Publication number: 20020073919
    Abstract: By using a semiconductor single crystal pulling apparatus for growing single crystals by the Czochralski method while rotating the melt by a magnetic field and electric current, namely by the EMCZ method, which comprises a main pulling means for pulling a single crystal, a holding mechanism for gripping an engaging stepped portion formed on the single crystal through engaging members and a sub pulling means for moving the holding mechanism up and down and in which an electric current is passed through the main pulling means and through the sub pulling means, it is possible to prevent heavy single crystals from undergoing a falling accident and, at the same time, effectively reduce the power consumption. In this pulling apparatus, it is effective to feed an electric current to the sub pulling means alone and it is desirable to dispose two or more electrodes whether the pulling means is of a shaft type or wire type.
    Type: Application
    Filed: October 17, 2001
    Publication date: June 20, 2002
    Inventors: Souroku Kawanishi, Masahito Watanabe, Minoru Eguchi
  • Publication number: 20010047749
    Abstract: An apparatus for growing a single crystal of semiconductor is provided, which makes it possible to grown a heavy single crystal of semiconductor of 100 kg or greater in weight even if a growing single crystal contains the neck. In the apparatus, the first and second electrodes are provided in such a way that the first ends of the first and second electrodes are electrically connected to the power supply and the second ends of the first and second electrodes are contacted with the melt in the crucible. During the growth process, a specific voltage is applied across the first ends of the first and second electrodes, thereby forming the electrical current path interconnecting the second ends of the first and second electrodes in the melt. The magnetic field is generated with the magnetic field generator to intersect with the electrical current path in the melt. No electric current flows through the growing single crystal from the melt.
    Type: Application
    Filed: March 6, 2001
    Publication date: December 6, 2001
    Applicant: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Publication number: 20010018889
    Abstract: In an apparatus for growing a semiconductor crystal from semiconductor melt, a crucible retains the semiconductor melt. An electrode contacts with the semiconductor melt and applies current to the semiconductor melt. The electrode is formed by the same material as the semiconductor crystal.
    Type: Application
    Filed: February 1, 2001
    Publication date: September 6, 2001
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 6221156
    Abstract: In an apparatus for growing a semiconductor crystal from semiconductor melt, a crucible retains the semiconductor melt. An electrode contacts with the semiconductor melt and applies current to the semiconductor melt. The electrode is formed of the same material as the semiconductor crystal.
    Type: Grant
    Filed: March 15, 1999
    Date of Patent: April 24, 2001
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 6077346
    Abstract: In the growth of a semiconductor single crystal according to the Czochralski method, a magnetic field is generated in a semiconductor melt and a current is supplied in the semiconductor melt in a direction perpendicular to the magnetic field. This makes it possible to cause the semiconductor melt to rotate spontaneously without rotating the crucible, thereby to grow a single crystal of semiconductor without striation even when growing a single crystal of semiconductor having a large diameter. Also it is made possible to exactly control the rotation rate of the semiconductor melt by changing the intensity of the magnetic field and the magnitude of the current independently. Further, the distribution of the rotation rates in the semiconductor melt can also be varied by changing the position of electrodes or electrode protecting tubes for immersing in the semiconductor melt.
    Type: Grant
    Filed: December 11, 1998
    Date of Patent: June 20, 2000
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 6048779
    Abstract: There is provided a method of growing silicon monocrystal by Czochralski method where cusp field is applied to molten silicon, including the step of applying cusp field to molten silicon so that a center of the cusp field is situated at a depth of one-third or greater of an entire depth of the molten silicon, the depth being defined as a distance from a surface level of the molten silicon. The method makes it possible to eliminate growth slits in all regions in a growth direction of grown silicon monocrystal, and in addition, to accomplish uniform oxygen concentration profile where a difference in an oxygen concentration in a direction of a diameter of crystal is equal to or smaller than 5%. Furthermore, the method makes it possible to eliminate growth slits in all regions in a growth direction in a large-diameter silicon monocrystal, for instance, having a 40 cm-diameter.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: April 11, 2000
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi
  • Patent number: 5367979
    Abstract: In a method of growing a monocrystalline silicon based on the Czochralski method, the thermal Rossby number is set to at least 80 to develop the convection of a liquid of melted silicon in an axially symmetric form. A tube made of quartz is inserted in the silicon liquid to supply oxygen thereto to control the oxygen density of a resultant crystal. According to this method, there can be grown a silicon monocrystal which contains oxygen in an arbitrary density range from 10.sup.15 /cm.sup.3 to 10.sup.18 /cm.sup.3 and which has a uniform oxygen density variation not exceeding 5% in a plane vertical to a direction of the crystal growth.
    Type: Grant
    Filed: January 14, 1993
    Date of Patent: November 29, 1994
    Assignee: NEC Corporation
    Inventors: Masahito Watanabe, Minoru Eguchi