Patents by Inventor Eiichi Miyakoshi

Eiichi Miyakoshi 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).

  • Method for recirculating high-temperature etching solution
    Patent number: 4980017
    Abstract: A method for recirculating a high-temperature etching solution according to the present invention comprises the steps of continuously removing, from a bath for etching a wafer for a semiconductor device, a portion of an etching solution contained in the etching bath, injecting a predetermined amount of pure water for adjusting the concentration of the etching solution into the removed etching solution, heating the resulting solution to a predetermined temperature, and recirculating the heated solution into the etching bath.
    Type: Grant
    Filed: September 26, 1989
    Date of Patent: December 25, 1990
    Assignee: Nisso Engineering Company, Ltd.
    Inventors: Toshimitsu Kaji, Tadao Takeuchi, Tsutomu Kawashima, Eiichi Miyakoshi, Yasukatsu Nishikata, Yasuya Hisatome