| 摘要 |
<p>PURPOSE:To refine a gas of ultrahigh purity without making existing gas-supply facilities useless and to produce a high-performance semiconductor device by a method wherein a means such as an adsorption type trap, a reaction type getter or the like is used immediately before a gas is introduced into a chamber. CONSTITUTION:An electrode 3 is placed inside a vacuum chamber 1; e.g., a silicon substrate 4 is placed on this electrode 3. A high-frequency power supply 6 is connected electrically to the electrode 3 via a matching box 5. A vacuum chamber 1 is connected to a gas refining unit via pipes 7, 8, 9 and an aggregate pipe 10 of the pipes. Because this is structured in such a way that adsorption columns 12a-12c composed mainly of activated charcoal are installed at the pipes 7-9 near the vacuum chamber, these columns can adsorb an impurity contained in a gas, especially water, even when an ordinary gas available on the market is used; it is possible to reduce an influence due to the impurity. Accordingly, it is possible to etch a substrate 2 easily to a highly selective and good shape.</p> |
