Patents by Inventor Gudrun Dietz

Gudrun Dietz 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).

  • Exposure of uniform fine pattern on photoresist
    Patent number: 4704348
    Abstract: Exposure of fine patterns on a photoresist is carried out by controlling the humidity and temperature of a gas to be supplied to an exposure apparatus separate from the ambient atmosphere.Temperature of the atmosphere at least in the vicinity of a photoresist is controlled in a predetermined range and air or gas to be supplied to the exposure space is humidified to a desired degree.Water content in the photoresist is kept uniform and constant by the specially controlled atmosphere and enables uniform pattern width of the exposed fine pattern all over the photoresist surface.
    Type: Grant
    Filed: September 25, 1985
    Date of Patent: November 3, 1987
    Assignees: Hitachi, Ltd., Veb Carl Zeiss Jena. DDR.
    Inventors: Yasuhiro Koizumi, Soichi Torisawa, Walter Gartner, Gudrun Dietz, Wolfgang Retschke