Process for purifying halogen-containing gas

摘要

There is disclosed a process for purifying a halogen-containing gas (halogen gas such as chlorine, fluorine alone or diluted with an inert gas) which comprises bringing the halogen-containing gas into contact with a purifying agent comprising a hydroxide of an alkaline earth metal such as strontium hydroxide and an iron oxide such as triiron tetraoxide to efficiently remove hydrogen halogenides such as hydrogen chloride and hydrogen fluoride along with moisture that are contained as impurities in the halogen-containing gas. The above process enables the formation of a non-corrosive halogen-containing gas having an extremely high purity and capable of being favorably used as etching gas for silicon films, aluminum alloy films, etc. in a semiconductor manufacturing process.