Patent ID: 8147222

Claim:
A vacuum system, comprising: a turbo-molecular pump having a plurality of rotor blades; a vacuum manifold formed from multiple vacuum chambers; and a vacuum divider for positioning between rotor blades of the turbo-molecular pump and the vacuum manifold, said vacuum divider having, a first coupling aperture passing through the vacuum divider for allowing gas to pass from a first of the multiple vacuum chambers to the turbo-molecular pump, and a second coupling aperture passing through the vacuum divider for allowing gas to pass from a second of the multiple vacuum chambers to the turbo-molecular pump; and wherein the vacuum divider has a rotor-blade-directed face and is fixed relative to the turbo-molecular pump so that the closest distance between the face and the rotor blades of the turbo-molecular pump is less than 30% of a minimum width of the rotor-blade-directed face separating the coupling apertures to provide a differential pumping ratio (“DPR”) between the first and second of the multiple vacuum chambers.