Conveyance system

Abstract

A wafer conveyance system is described for transporting one or more wafers that undergo, while being transported, different processes at a plurality of wafer processing apparatuses inside which one or more wares are processed. A hermetically closed chamber is provided that defines an isolated environment inside which a controlled atmosphere. At least one guide path is provided inside the hermetically closed chamber. At least one mobile element is movable inside the hermetically closed chamber along the at least one guide path to transport one or more wafers from one wafer processing apparatus to another. A plurality of position sensors that detect positions of the at least one mobile element are deployed along each of the at least one guide path in such a manner that they are deployed at intervals close together when near the wafer processing apparatuses and deployed at wider intervals elsewhere. In another aspect, the guide rails may be constructed of a plurality of connectable rail units. Because the guide rail can be disconnected and/or connected between rail units having position sensors, rearrangement and/or reattachment of the plurality of position sensors is not necessary when changing a configuration and/or extending the layout of the guide rail.