| abstract |
The first chamber cleaning gas and the first silicon-containing film-etching gas of the present invention comprise at least one compound selected from the group consisting of FCOF, CF3OCOF and CF3OCF2OCOF, and O2 in the specific amount, and optionally other gases. The second chamber cleaning gas and the second silicon-containing film-etching gas comprise CF3COF, C3F7COF or CF2(COF)2 and O2 in specific amounts, and optionally may comprise other gases. The chamber cleaning gases and silicon-containing film etching gases of the present invention have a low global warming potential and hardly generate substances in the exhaust gases such as CF4, etc, which are harmful to the environment and have been perceived as contributing to global warming. Therefore, the gases are friendly to the global environment, and have easy handling and excellent exhaust gas treating properties. Further, the chamber cleaning gases of the invention have excellent cleaning rate. |