Patents by Inventor Toshiaki Koshitaka

Toshiaki Koshitaka 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: 20100136799
    Abstract: A method of manufacturing a semiconductor device includes a first absorption step, a releasing step, a second absorption step, and an exposure step. In the first absorption step, a wafer chuck of a wafer stage absorbs the semiconductor wafer to adjust the temperature of the semiconductor wafer. In the releasing step, the semiconductor wafer is released from the wafer chuck. In the second absorption step, a wafer chuck of a wafer stage for exposure absorbs the semiconductor wafer. In the exposure step, the semiconductor wafer is exposed.
    Type: Application
    Filed: November 24, 2009
    Publication date: June 3, 2010
    Applicant: NEC ELECTRONICS CORPORATION
    Inventor: Toshiaki Koshitaka
  • Publication number: 20020056205
    Abstract: The alignment marks of the present invention, which are to be used for alignment of a wafer, have a slit pattern with a plurality of slits arranged upon the wafer; and a dot pattern with a plurality of dots arranged along the length of the slits at the outer regions of two of the plurality of slits, which are at the ends thereof.
    Type: Application
    Filed: November 9, 2001
    Publication date: May 16, 2002
    Applicant: NEC Corporation
    Inventor: Toshiaki Koshitaka
  • Patent number: 6315912
    Abstract: In a process for forming a lower electrode of a cylindrical capacitor in a semiconductor memory, a polysilicon film is formed on an insulator film to cover an inner surface of a hole formed in the insulator film. An exposed surface of the polysilicon film is treated with a reaction accelerator which reacts with a positive photoresist to lower dissolubility of the positive photoresist to a developer liquid. The positive photoresist is deposited on the whole surface to fill up the hole. As a result, the positive photoresist filled up within the hole reacts with the reaction accelerator within the hole and becomes difficult to dissolve to the developer liquid even after the positive photoresist is exposed to light. The whole of the positive photoresist is exposed to light and then developed with the developer so that the positive photoresist remains only within the hole.
    Type: Grant
    Filed: February 22, 2000
    Date of Patent: November 13, 2001
    Assignee: NEC Corporation
    Inventors: Toshiaki Koshitaka, Tadahisa Fukushima