VACUUM PROCESSING APPARATUS WITH LOW PARTICLE GENERATING VACUUM SEAL

摘要

A wafer processing apparatus (10) is provided with sealing ports (15) between adjacent evacuatable chambers (11 and 16) that are actuated to compress elastomeric seals (26) carried by the valve sealing elements (23) to differing degrees of compression, based on the amount of pressure differential between the chambers (11 and 16) when sealed. The degree of compression is controlled so that less compression of the seal (26) takes place when less is required to seal, such as with lower pressure differentials, thereby avoiding unnecessary fatigue and wear of and around the seals (26) that would otherwise increase the generation of particulate contamination.