| 摘要 |
PROBLEM TO BE SOLVED: To minimize contamination in distribution of ultra high purity gas, by wet-cleaning a gas distribution network and then performing liquid drying with a specific H2 O desorbing liquid drying agent during distribution of the ultra high purity gas used for treatment of electronic material. SOLUTION: In distribution of ultra high purity gas, prior to the distribution process, cleaning liquid 25 is first supplied to a distribution network for cleaning from a pump 24 for cleaning. Then, the gas distribution network is liquid-dried with a H2 O desorbing liquid drying agent selected from a group comprising acetone dimethylacetal, 2-2 dichloropropane, 2-2 dibromopropane, mixtures thereof, and an equivalent. Next, the distribution network is purged with dry inert high purity gas comprising less than 1 ppm of any impurity, is exhausted at a pressure which is lower than 5×10<4> Pa with an operation of a vacuum pump 19, and then is exposed to atmosphere containing high purity corrosive gas.
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