Patents by Inventor Tetsu Ohsawa

Tetsu Ohsawa 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).

  • Patent number: 6033215
    Abstract: A heat treatment boat houses a plurality of semiconductor wafers in a manner separated at intervals for heat-treating the wafers in a heat treatment furnace. The heat treatment boat includes a bottom plate, a first support rod erected on the outer peripheral edge of the bottom plate, a second support rod and a third support rod both erected on the bottom plate so as to make an central angle of 105.degree. to 120.degree. with the first support rod with respect to the center of the respective wafer supported by the rods, and a top plate provided opposed to the bottom plate for holding the rods. The stresses applied to the wafers housed in the heat treatment boat are distributed equivalently to three contacting points with the rods and become the minimum.
    Type: Grant
    Filed: September 23, 1997
    Date of Patent: March 7, 2000
    Assignees: Tokyo Electron Limited, Tokyo Electron Tohoku Limited
    Inventor: Tetsu Ohsawa
  • Patent number: 5645419
    Abstract: A heat treatment device including a handling chamber that has a carriers feed in/out opening for carriers holding plural sheets of objects to be treated parallelly vertical, a vertical heat treatment furnace for heat treating the objects and a posture changer for swinging the carriers near the carriers feed in/out opening of the handling chamber on a rotational center into a territory of lower sides of the carriers to change the posture of the objects to be treated from the vertical position to the horizontal position. The heat treatment device also has a carriers storage unit disposed above the posture changing means for storing a plural number of posture changed carriers, conveying device for conveying the carriers between the storage unit and the posture changing device and the heat treatment furnace side. Also, provided is a transferrer for transferring the objects-to-be-treated to/from an objects-to-be-treated holder for loading and unloading into/out of the heat treatment furnace side.
    Type: Grant
    Filed: March 23, 1995
    Date of Patent: July 8, 1997
    Assignees: Tokyo Electron Kabushiki Kaisha, Tokyo Electron Tohoku Kabushiki Kaisha
    Inventors: Tetsu Ohsawa, Hiroyuki Iwai, Hisashi Kikuchi, Shingo Watanabe, Keiji Takano, Tsutomu Haraoka, Ken Nakao
  • Patent number: 5586880
    Abstract: A heat treatment boat houses a plurality of semiconductor wafers in a manner separated at intervals for heat-treating the wafers in a heat treatment furnace. The heat treatment boat includes a bottom plate, a first support rod erected on the outer peripheral edge of the bottom plate, a second support rod and a third support rod both erected on the bottom plate so as to make an central angle of 105.degree. to 120.degree. with the first support rod with respect to the center of the respective wafer supported by the rods, and a top plate provided opposed to the bottom plate for holding the rods. The stresses applied to the wafers housed in the heat treatment boat are distributed equivalently to three contacting points with the rods and become the minimum.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: December 24, 1996
    Assignees: Tokyo Electron Limited, Tokyo Electron Tohoku Limited
    Inventor: Tetsu Ohsawa
  • Patent number: 5540098
    Abstract: A transfer device an ultrasonic sensor having an oscillating section for oscillating an ultrasonic beam toward wafers which are horizontally arranged in a carrier and a receiving section for receiving a reflected ultrasonic wave, and driving mechanism for vertically moving the ultrasonic sensor relative to the carrier so as to sequentially radiate an ultrasonic beam to the end faces of the wafers. The presence/absence of a wafer and projection of the wafer in and from the carrier are detected based on the reflected wave received by the receiving section.
    Type: Grant
    Filed: February 16, 1994
    Date of Patent: July 30, 1996
    Assignees: Tokyo Electron Limited, Tokyo Electron Tohoku Limited
    Inventor: Tetsu Ohsawa
  • Patent number: 5464313
    Abstract: A heat treatment apparatus for semiconductor wafers is provided with a number, such as two, of heat treatment units which are arranged horizontally and which load wafer boats containing wafers from below. A wafer delivery section is provided to correspond to each of the two heat treatment units, and wafers are conveyed by a wafer transfer mechanism between the wafer delivery section and the heat treatment units. Carrier accommodation racks are provided in upper and lower positions across the two heat treatment units in such a manner that they can be used in common for both wafer delivery sections. The carrier transfer mechanism is provided in front of the two carrier accommodation racks in order to convey carriers containing wafers between carrier stages at front portions of the wafer heat treatment apparatus, the two carrier accommodation racks, and the two wafer delivery sections.
    Type: Grant
    Filed: February 4, 1994
    Date of Patent: November 7, 1995
    Assignees: Tokyo Electron Kabushiki Kaisha, Tokyo Electron Tohoku Kabushiki Kaisha
    Inventor: Tetsu Ohsawa
  • Patent number: 5433784
    Abstract: The vertical treating apparatus according to this invention comprises as major units a process tube for receiving objects to be treated through an opening in a lower part thereof, a lift mechanism (boat elevator) for mounting a wafer boat holding the wafers to load the wafers into the process tube, and a wafer transfer device for transferring the wafers to the lift mechanism. The lift mechanism flexibly supports a cap for closing the opening of the process tube by way of an urging force provided by coil springs, and mounts the wafer boat for holding the wafers on the upper surface thereof. A cap restricting member is provided for restricting the urging force of the coil springs. The cap is provided at a lowermost position of the lift mechanism. Thus, the cap is restricted by the cap restricting member when the wafers are transferred by the transfer device, whereby the wafer boat, etc.
    Type: Grant
    Filed: January 11, 1994
    Date of Patent: July 18, 1995
    Assignees: Tokyo Electron Kabushiki Kaisha, Tokyo Electron Tohoku Kabushiki Kaisha
    Inventors: Katsushin Miyagi, Tetsu Ohsawa
  • Patent number: 5407181
    Abstract: This invention relates to a vertical heat treating device of a two-boat system including below a vertical reaction furnace a first waiting position where a treated boat waits, and second waiting position where a boat to be next treated waits. The device comprises boat transferring device for transfer wafers at the first and the second waiting positions and at the vertical reaction furnace. The boat transferring device can be displaced in a two-dimensional plane at least including rotation and radial displacement from the rotation center. A heat shielding member is also provided for hindering thermal influence between the first and the second waiting positions so that the first and the second waiting positions can be positioned as near each other as possible to minimize a space occupied by the boat transferring device, whereby the vertical heat treating device can be made smaller-sized.
    Type: Grant
    Filed: November 26, 1993
    Date of Patent: April 18, 1995
    Assignees: Tokyo Electron Kabushiki Kaisha, Tokyo Electron Tohoku Kabushiki Kaisha
    Inventor: Tetsu Ohsawa
  • Patent number: 5064337
    Abstract: A handling apparatus, used for handling a carrier of semiconductor wafers, comprises a first mechanism for transferring a carrier between a loader/unloader table and a storage compartment, and a second mechanism, for moving the first mechanism in both vertical and horizontal directions. The first mechanism includes an arm, a loading portion for loading the carrier, and an arm-rocking mechanism. The second mechanism moves the first mechanism to the loader/unloader table, picks up the carrier, and then moves the first mechanism to the storage compartment, where the arm is rocked, so as to discharge the object from the loading portion.
    Type: Grant
    Filed: July 12, 1990
    Date of Patent: November 12, 1991
    Assignee: Tokyo Electron Limited
    Inventors: Teruo Asakawa, Tetsu Ohsawa