Method and device for delivering a pure gas charged with a predetermined quantity of at least one gaseous impurity to an apparatus

摘要

A method of delivering a pure gas charged with a predetermined quantity of at least one gaseous impurity to an apparatus, comprising the steps of mixing at least two different auxiliary gases, including the impurity to form a mixture, diluting a sampled quantity of the mixture in the pure gas in a predetermined manner, delivering the pure gas charged with the impurity to the apparatus, wherein the auxiliary gases are stored in a reservoir in the form of a mixture of known composition, most of the auxiliary gases in the mixture having volume concentrations substantially of the same order of magnitude.