Abstract: The substrates supported in substrate holders are carried on holder carriers in a manner, that their extended surfaces are exposed to the surrounding atmosphere along an extended surface of the holder carriers. The holder carriers include an axis traverse to their extended surface. The substrates on a holder carrier are vacuum treated in a vacuum treatment chamber. This chamber communicates via a gate valve with a transfer vacuum chamber. A holder carrier with substrates in the vacuum treatment chamber is exchanged with a holder carrier carrying untreated substrates from the transfer vacuum chamber 23 by means of an exchange robot. During treatment in the vacuum treatment chamber, holder carriers with treated substrates and holder carriers with untreated substrates are exchanged in the transfer vacuum chamber through a gate valve. The transfer vacuum chamber acts as a load-lock.