Patents by Inventor Yohji Ogawa

Yohji Ogawa 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).

  • Apparatus for preventing clouding of a semiconductor wafer
    Patent number: 5122170
    Abstract: An apparatus for preventing clouding of a mirror-finished semiconductor wafer in a semiconductor wafer treating zone by controlling an internal atmosphere in the semiconductor wafer treating zone. The apparatus has an air conditioner for introducing the air from an external environment into the semiconductor wafer treating zone, and a removing device disposed in the air conditioner or between the air conditioner and the external environment for removing at least part of the sulfur oxides out of the sulfur oxides and nitrogen oxides in the air introduced from the external environment. The air introduced through the air conditioner and the cleaning device forms an atmosphere including a sulfur oxide concentration of 60 ng/l or less in the semiconductor wafer treating zone.
    Type: Grant
    Filed: May 31, 1991
    Date of Patent: June 16, 1992
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Kazuo Satoh, Yohji Ogawa, Hirofumi Okano, Kiyomi Suzuki
  • Apparatus for preventing clouding of a semiconductor wafer
    Patent number: 5039321
    Abstract: An apparatus for preventing clouding of a mirror-finished semiconductor wafer in a semiconductor wafer treating zone by controlling an internal atmosphere in the semiconductor wafer treating zone. The apparatus has an air conditioner for introducing the air from an external environment into the semiconductor wafer treating zone, and a removing device disposed in the air conditioner or between the air conditioner and the external environment for removing at least part of the sulfur oxides out of the sulfur oxides and nitrogen oxides in the air introduced from the external environment. The air introduced through the air conditioner and the cleaning device forms an atmosphere including a sulfur oxide concentration of 60 ng/l or less in the semiconductor wafer treating zone.
    Type: Grant
    Filed: October 31, 1989
    Date of Patent: August 13, 1991
    Assignee: Toshiba Ceramics Co., Ltd.
    Inventors: Kazuo Satoh, Yohji Ogawa, Hirofumi Okano, Kiyomi Suzuki