| 摘要 |
PROBLEM TO BE SOLVED: To provide a chamber capable of preventing intrusion of dust accumulated on the bottom surface in a vacuum chamber into the gap between a bellows and a lifting tube through a port after rolling on the bottom surface. SOLUTION: An annular barrier 14 is provided on the bottom surface in a chamber 1 along the peripheral edge of a port 4, in order to prevent the dust rolling on the bottom surface 1c in the vacuum chamber 1 from entering the gap between a bellows 7 and a lifting tube 5 through the port 4. COPYRIGHT: (C)2004,JPO&NCIPI |
