Method for plasma etching

Abstract

Abstract PURPOSE:To obtain the state wherein an anisotropic etching is easily accomplished and to have the state suited for employment of microscopic working technique by a method wherein a mixed gas, in which hydrogen gas is added besides chlorine reaction gas, is used as the reaction gas to be used when a plasma etching is performed on aluminum or an aluminum alloy. CONSTITUTION:A mixed gas in which hydrogen gas is added besides carbon tetrachloride and trichloroboron is used as the reaction gas to be used when a plasma etching is performed on aluminum. When said plasma etching is going to be performed, a hydrocarbon polymer is grown on the side wall part of an aluminum film, and an anisotropic etching can be accomplished. This hydrocarbon polymer can be removed easily by performing an oxygen plasma treatment. The content of hydrogen gas of approximately 10-50vol% is considered practicable. When hydrogen gas is mixed, cathode dropping voltage is boosted, an anisotropic etching can be accomplished even when making power density is low, and the ratio of selectivity can be increased.

Inventors

• 👤 Masaki Shintani
• 👤 正樹 新谷

Bibliographic Details