| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a method for purifying COF<SB>2</SB>used as a cleaning gas or an etching gas. <P>SOLUTION: The vapor of COF<SB>2</SB>is sucked under a reduced pressure at -160°C to -100°C from the COF<SB>2</SB>containing impurities each having the boiling point close to that of COF<SB>2</SB>or impurities each having the boiling point higher than that of COF<SB>2</SB>. <P>COPYRIGHT: (C)2003,JPO |
