Patents Examined by Thi Dung
  • Patent number: 5007984
    Abstract: A method for etching a chromium film includes the steps of forming a resist having a phenol novolak resin as a principal chain on the chromium film formed on a substrate, and etching the chromium film using an etchant while stripping off the resist from the chromium film using an etchant containing nitric acid. A second method for etching a chromium film comprises the steps of forming an aluminum film or an aluminum alloy film on the chromium film formed on a substrate, forming a resist having a predetermined pattern on the aluminum film or the aluminum alloy film, etching the aluminum film or the aluminum alloy film and the chromium film using phosphoric acid, and removing by etching the aluminum film or the aluminum alloy film using phosphoric acid containing nitric acid after removing the resist.
    Type: Grant
    Filed: September 27, 1988
    Date of Patent: April 16, 1991
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Michinari Tsutsumi, Atsushi Endo, Toshio Yada