Patent ID: 8735765

Claim:
A lateral bellows unit for a cantilever assembly of a plasma processing chamber for processing a substrate wherein a sidewall separates the interior of the chamber into first and second regions in fluid communication via an opening in the sidewall, the bellows unit comprising: a fixed annular plate which mounts on the sidewall of the chamber with an opening in the annular plate surrounding the opening in the sidewall; a movable plate which attaches to an end of the arm unit outside the first and second regions, the arm unit configured to extend horizontally through the opening in the sidewall such that a first end is in the first region and a second end is in the second region defined by the bellows, a substrate support being located on an upper portion of the first end; a bellows extending between the fixed annular plate and the movable plate, the fixed plate, wherein (a) an upper portion of the bellows is compressed and a lower portion of the bellows is expanded when the arm unit is moved to an uppermost position and (b) an upper portion of the bellows is expanded and a lower portion of the bellows is compressed when the arm unit is moved to a lowermost position.