Patents by Inventor Hidehito Fukushima

Hidehito Fukushima 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).

  • Remover solvent for partial removal of photoresist layer
    Patent number: 6117623
    Abstract: While it is important in the photolithographic patterning of a photoresist layer on a substrate surface for the manufacture of various electronic devices that the pattern-wise light exposure of the photoresist layer is preceded by partial removal of the photoresist layer on the non-patterning areas such as marginal areas, peripheral areas and back surface opposite to the surface for resist patterning by dissolving away the extraneous photoresist layer with a remover solvent, the invention proposes an improvement in the partial removal of the photoresist layer by using a specific organic solvent or solvent mixture selected relative to the surface tension of the solvent which, in particular, is a mixture of .gamma.-butyrolactone and anisole in a mixing ratio of 70:30 to 97:3 by weight.
    Type: Grant
    Filed: December 2, 1999
    Date of Patent: September 12, 2000
    Assignee: Tokyo Ohka Kogyo Co., Ltd.
    Inventors: Jun Koshiyama, Futoshi Shimai, Hidehito Fukushima