Two-wafer loadlock wafer processing apparatus and loading and unloading

Abstract

Wafers from plural non-vacuum multiple wafer carriers are loaded and unloaded in an atmospheric front end of a wafer processing machine and transferred to and from a high vacuum chamber of a transfer module of a wafer processing cluster tool, or back end, through a single two-wafer loadlock. Preferably, with the wafers oriented horizontally throughout, two wafers are sequentially loaded into and simultaneously moved inbound to the high vacuum back end of the system, through one loadlock and sequentially moved into and simultaneously moved outbound through the same loadlock, the loadlock having a pair of water cooled supports for simultaneously actively cooling the two wafers. In both the atmospheric front end and vacuum back end environments, transfer arms load and unload the loadlock, and transfer wafers within the environments when all loadlocks are sealed. Preferably, two wafers are actively cooled in the loadlock. Preferably also, wafers are passed through a wafer aligner after being removed from a carrier and before placed in the loadlock. When two wafers are removed from the loadlock into the vacuum back end, one or two wafers may be temporarily held in a buffer position within the back end vacuum chamber.