Metal film etching method
AssigneesKabushiki Kaisha Toshiba, Shibaura Engineering Works Co., Ltd.
InventorsKei Hattori, Akira Kobayashi, Mikio Nonaka, Makoto Muto, Masaru Kasai, Toshiyasu Onoda, Tomoaki Yoshimori
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Abstract
A metal film etching method etches selectively a metal film formed on a layer insulating film provided with viaholes so as to cover the surface of the layer insulating film and fill up the viaholes so that the metal film excluding portions there of filling up the viaholes are removed completely without forming a pit in the portions of the metal film filling up the viaholes. The metal film etching method uses a mixed reactive gas of a gas containing fluorine atoms, a gas containing chlorine atoms and oxygen gas.
Claims6
A metal film etching method comprising etching a metal film formed on a layer insulating film provided with viaholes formed by etching, so as to cover the layer insulating film and fill up the viaholes, to remove the metal film excluding portions thereof deposited in the viaholes, carrying out said metal film etching method using a mixed reactive gas of a gas containing fluorine atoms, a gas containing chlorine atoms and oxygen gas for etching the metal film and wherein the metal film is a tungsten film or a tungsten alloy film formed on a film consisting of a titanium film and/or titanium compound film, and the tungsten film or the tungsten alloy film is etched selectively over the titanium film and/or the titanium compound film.
Dependencies are inferred from the claim text.