Purity Grade 99.999% Formula CF4 Application Tetrafluoromethane is sometimes used as a low temperature refrigerant. It is used in electronics microfabrication alone or in combination with oxygen as a plasma etchant for silicon, silicon dioxide, and silicon nitride. Alternative Name Carbon tetrafluoride, Perfluoromethane, Tetrafluorocarbon, Freon 14, Halon 14, Arcton 0, CFC 14, PFC 14, R 14,UN 1982 Molecular Weight 88.0043g/ mol CAS No. 75-73-0 Package 44L 49L