Patents by Inventor Masahiko Baba

Masahiko Baba 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: 20080168866
    Abstract: A method of manufacturing a honeycomb structure-body molding die formed with material feed holes and slit recesses formed in a lattice pattern in communication with the material feed holes, respectively, for molding the material into a honeycomb shape is disclosed. The method comprises a preparing step, a feed-hole forming step and a slit-recess forming step. In the slit-recess forming step, grinding work is conducted using a disc-like thin-blade grinding stone to form non-communication slit recesses on the slit-processing surface each in a depth not to communicate with the material feed holes (in a non-communication grinding process). Then, the grinding work is further conducted to grind the non-communication slit recesses into the slit recesses until the slit recesses are brought into communication with the material feed holes (in a communication grinding process).
    Type: Application
    Filed: January 14, 2008
    Publication date: July 17, 2008
    Applicant: DENSO CORPORATION
    Inventor: Masahiko BABA
  • Patent number: 6228165
    Abstract: A method of manufacturing a crystal of silicon in accordance with a Czochralski method, includes the steps of applying an electric potential across a quartz crucible containing a silicon melt, and pulling a crystal of silicon from the silicon melt.
    Type: Grant
    Filed: July 28, 1999
    Date of Patent: May 8, 2001
    Assignee: Seh America, Inc.
    Inventors: Masahiko Baba, Scott Matthew Kirkland, Richard William Rudberg, Susumu Sonokawa, Darren Mark Taie, Akira Uchikawa
  • Patent number: 6030451
    Abstract: A method and apparatus for measuring and controlling the diameter of a silicon single crystal ingot grown by the Czochralski technique using dual optical cameras focused on diametrically opposed edges of the meniscus of the growing crystal to measure the actual crystal diameter. The crystal growth parameters can be adjusted in response to the measured diameter to maintain a constant, desired diameter. The method and apparatus of the invention provide a continuous accurate measurement of the crystal diameter and avoid unnecessary adjustments to the crystal growth conditions resulting from diameter measurement errors due to the effects of crystal orbit, melt level changes and camera angle variations.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: February 29, 2000
    Assignee: SEH America, Inc.
    Inventors: Aaron LaBrie, Masahiko Baba
  • Patent number: 5584930
    Abstract: A method for measuring a diameter of a single crystal ingot pulled up in a single crystal pulling apparatus comprising: calculating the weight of the pulled-up single crystal, calculating the descent amount of the melt surface relative to the crucible wall from the calculated pulled-up weight of the grown single crystal, and then either correcting the value of the ingot diameter actually measured by the optical sensor in response to the descent amount of the melt surface level or raising the crucible by an amount equal to the descent amount of the surface level.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: December 17, 1996
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Nobuo Katsuoka, Yoshihiro Hirano, Atsushi Ozaki, Masahiko Baba
  • Patent number: 5378900
    Abstract: The growing portion of a single crystal 1 grown by the pull method is recorded and the image signal is output to a digitizing circuit 3 that converts the image signal into binary data. A memory device 4 stores the digitized images and the point P at the boundary between dark and light is detected by scanning the stored digitized images starting from the scanning-start pixel and proceeding in the direction parallel to the direction of single crystal pulling. The diameter D of the growing portion of the single crystal is determined based upon the boundary P, and the scanning-start pixel for the current operation is set at the pixel that is separated from the boundary Pb in the preceding operation by a preset number of pixels d in the opposite direction of the scan.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: January 3, 1995
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Yoshihiro Hirano, Masahiko Baba
  • Patent number: 5269875
    Abstract: Used in a Si crystal pulling apparatus using the Czochralski method, to lower the concentration of oxygen in the Si single crystal without increasing the production cost and to make the concentration substantially even all over the Si single crystal. The crystal 36 is produced by disposing a straightening tube 40 concentrically with and above a quartz crucible 22, letting inert gas flow down through the tube, dipping a seed crystal in Si molten liquid 28 in the quartz crucible and then pulling the seed crystal up. The concentration of oxygen in the Si single crystal is adjusted by controlling the distance H between the surface of the Si molten liquid and the bottom end of the straightening tube in accordance with the pull-up length Y or the pull-up time from a certain growth point of the crystal.
    Type: Grant
    Filed: January 24, 1992
    Date of Patent: December 14, 1993
    Assignee: Shin-Etsu Handotai Company, Limited
    Inventors: Susumu Sonokawa, Kenji Araki, Atsushi Iwasaki, Masahiko Baba
  • Patent number: 5240684
    Abstract: A device for measuring the diameter of the growing portions of the single crystals grown by the Czochralski technique is provided. This device is capable of measuring the crystal diameter with a high degree of accuracy over a wide range from the small-diameter portion thereof to the large diameter portion. A one-dimensional camera 28 and a two-dimensional camera 48 are fixed to a shoulder chamber 34 in such a manner that the optical axes thereof are parallel to each other. An optical path switch-over device, consisting of a cylinder 56, a movable plane mirror 52 mounted on a cylinder rod, and a fixed plane mirror 54, is provided. When the diameter of a neck portion of the single crystal 20 having a diameter of 10 mm or less is measured, the light reflected by the plane mirrors 52 and 54 is made incident on the two-dimensional camera 48, and the diameter of a bright ring 27 is measured on the basis of the image obtained by the two-dimensional camera.
    Type: Grant
    Filed: July 29, 1991
    Date of Patent: August 31, 1993
    Assignee: Shin-Etsu Handotai Company, Limited
    Inventors: Masahiko Baba, Hiroyuki Ibe
  • Patent number: 5183528
    Abstract: A method for automatically controlling growing a single crystal neck portion by the CZ method, comprising the steps of pulling up a seed crystal (30) at 2 mm/min. for five minutes so as to grow a single crystal 32; next measuring a diameter of the lower end of the crystal; modifying an electric power for heating a melt based on the difference between the measured diameter and a reference value; waiting for five minutes; keeping the electric power constant for 10 minutes with controlling the pulling up speed so as to approach the diameter of the crystal to the reference value and with measuring the pulling up speed repeatedly; and next modifying the power based on the difference between the mean speed and a reference value. The last two steps are repeated alternatively.
    Type: Grant
    Filed: February 28, 1991
    Date of Patent: February 2, 1993
    Assignee: Shin-Etsu Handotai Company, Limited
    Inventors: Masahiko Baba, Hiroshi Ohtsuna
  • Patent number: 5170061
    Abstract: A method and an apparatus for measuring oscillation of a melt surface in growing a single crystal by Czochralski process, particularly in growing and pulling a crystal neck portion having a small diameter of 2 to 5 mm. The image of a region where the single crystal is being grown by the Czochralski process is taken by a camera 38 and the outside diameter D.sub.o of a bright ring image 70 of a brightness not lower than a predetermined reference value E is detected in accordance with video signals produced by the camera (Steps 80-83). The amount of oscillation of the outside diameter D.sub.o is measured as the amount S.sub.v of oscillation of the melt surface near the region where the single crystal is grown. The reference value E is determined by multiplying the maximum value of the video signals in one field with a predetermined constant K. The constant K is a value which, when the velocity of pulling of the single crystal is fixed to zero, substantially maximizes the amount of S.sub.
    Type: Grant
    Filed: April 29, 1991
    Date of Patent: December 8, 1992
    Assignee: Shin-Etsu Handotai Company, Limited
    Inventor: Masahiko Baba
  • Patent number: 5138179
    Abstract: Disclosed are a method of and a device for crystal diameter measurement in an apparatus for automatically controlling single crystal growth by the CZ technique. In the diameter measurement method, a growing region of a single crystal 32 is photographed by a camera 38, and an outer diamter Do of a luminous ring image 70 having a luminance above a reference value E is detected from a video signal supplied from the camera 38, the diameter Do thus detected being used for crystal diameter control.
    Type: Grant
    Filed: March 29, 1991
    Date of Patent: August 11, 1992
    Assignee: Shin-Etsu Handotai Company, Limited
    Inventors: Masahiko Baba, Hiroshi Ohtsuna
  • Patent number: 5129986
    Abstract: A method for controlling a specific resistance of a single crystal in a Czochralski-method type single crystal pulling apparatus having a hermetical chamber in which the single crystal is pulled up from a polycrystal melt and an inert gas supply and exhaust system by means of which an inert gas is supplied to the hermetical chamber and exhausted therefrom; the method being characterized in that the pneumatic pressure in the hermetical chamber and the supply rate of the inert gas are controlled in accordance with a prepared control pattern with respect to the passage of pulling time.
    Type: Grant
    Filed: November 16, 1990
    Date of Patent: July 14, 1992
    Assignee: Shin-Etsu Handotai Co., Ltd.
    Inventors: Hidetoshi Seki, Seiichiro Ohtsuka, Masahiko Baba
  • Patent number: 5089238
    Abstract: Used in an apparatus for pulling a Si single crystal 36 up from Si molten liquid 35 by using the Czochralski method. In order to produce a Si single crystal having a desired quality, the diameter of the Si single crystal is controlled by controlling the pull-up speed of the Si single crystal, the sum of a reference temperature set value T.sub.B (X), which is a function of a pull-up distance X of the Si single crystal from a certain growth point, and a value proportional to a diameter deviation .DELTA.D is regarded as a reference temperature, and electric power supplied to a heater (24) for heating the Si molten liquid is controlled so that the temperature of the vicinity of the heater is equal to the reference temperature.
    Type: Grant
    Filed: October 22, 1990
    Date of Patent: February 18, 1992
    Assignee: Shin-Etsu Handotai Company Limited
    Inventors: Kenji Araki, Akiho Maeda, Masahiko Baba
  • Patent number: 4794263
    Abstract: An apparatus for measuring the diameter of a crystal in which an optical sensor scans along a sensing line which crosses at one point a luminous ring formed at the interface between a crystalline rod and a melt; the picture element position corresponding to a maximum luminance is discriminated when the optical sensor scans; the mean value of the picture element position is calculated over at least one revolution of the crystalline rod; and the diameter D of the crystalline rod at a portion thereof interfacing with the melt is calculated from the mean value and the level of the melt. Similarly, the minimum crystal diameter can be calculated by obtaining the picture element position corresponding to the minimum crystal diameter instead of obtaining the mean of the picture element position.
    Type: Grant
    Filed: October 19, 1987
    Date of Patent: December 27, 1988
    Assignee: Shinetsu Handotai Kabushiki Kaisha
    Inventors: Nobuo Katsuoka, Yoshihiro Hirano, Atsushi Ozaki, Masahiko Baba