Excimer laser gas refining - using alkali or alkaline earth metal to remove carbon tetra:fluoride

摘要

In the refining of an excimer laser gas contg. rare gas(es), a fluorine source gas and impurities (opt. including CF4) by sequential contact of the gas with highly reactive metal(s) to convert the fluorine source gas into metal fluoride(s) solid alkali (ne earth) metal cpd(s) to convert most of the fluorides into solid fluorides, and zeolite to remove most of the remaining impurities by adsorption the novelty is that the remaining gas is subsequently contacted with alkali and/or alkaline earth metal(s) at elevated temp. to decompose the CF4 and form a solid metal fluoride and carbon.