Work-piece treatment system having load lock and buffer

For use with a tool for treating a work-piece at sub-atmospheric pressure, transfer apparatus comprising:

• a) an enclosure defining a low pressure region for treatment of work-pieces placed at a work-piece treatment station within the low pressure region;
• b) multiple work-piece isolation load locks for transferring work-pieces, one or two at a time, from higher pressure to lower pressure for treatment and back to said higher pressure subsequent to said treatment, wherein the load locks undergo a pressurization and evacuation cycle to transfer the one or two work-pieces between the higher pressure and the lower pressure;
• c) a first robot including multiple independently operable transfer arms having a common pivot axis for transferring work-pieces within low pressure region from the load locks to a treatment station within the low pressure region;
• d) multiple other robots positioned outside the low pressure region for transferring work-pieces to and from the multiple work-piece isolation load locks from a source of said work-pieces prior to treatment and to a destination of said work-pieces after said treatment;
• and
• e) a low pressure buffer that is maintained at lower pressure dining successive pressurization and evacuation cycles of the load lock, the buffer being for storing a plurality of work-pieces at the lower pressure in positions within the buffer accessible for automated transfer into and out of said buffer.