| 摘要 |
<p>A process for preventing or removing deposits in the exhaust gas region (27) of a vacuum installation (5) is proposed, in which a gas containing constituents that can be deposited in the exhaust gas region (27) is pumped at least intermittently out of a vacuum chamber (10) which communicates by way of a gas pipe (11) with a vacuum pump (12). To that end, there is mixed with the gas, at least intermittently, immediately upstream of or inside the vacuum pump (12), a reactive gas that prevents deposits from the gas forming inside the vacuum pump (12) and/or in components located downstream thereof and/or that reduces or removes deposits already formed therein. The proposed process is suitable especially in the anisotropic plasma etching of silicon with alternate etching steps and polymerisation steps, in which a sulfur-containing etching gas is supplied to the vacuum chamber (10) during the etching steps and a gas containing a polymer-forming compound is supplied to the vacuum chamber (10) during the polymerisation steps.</p> |
