摘要 |
PROBLEM TO BE SOLVED: To provide a vacuum chamber, which is enhanced in operating efficiency by a method where a time required for reaction products such as halides produced by reaction on a halogen corrosive gas to separate off from the inner wall of the chamber as particles is elongated, and maintenance operations which are carried out periodically are lessened in frequency. SOLUTION: At least a part of a vacuum chamber, such as a chamber or a bell jar exposed to halogen corrosive gas and/or plasma, is formed of a sintered body whose main component is a compound of yttria with alumina, and the inner wall of the sintered body is partially roughened into a roughened surface whose surface roughness is Ra 0.5 to 10 μm. |