Abstract: A manufacturing system and method for processing semiconductor wafers through a plurality of processing stations that perform manufacturing operations on wafers includes a plurality of processing stations, each of which are capable of performing at least one processing operation on a wafer, each of the processing stations having a controlled environment for processing the wafers, and a branched tunnel joined and communicating with the controlled environment. A means is provided for maintaining a clean environment in the tunnel. Within the tunnel there are provided a plurality of guided transport vehicles adapted to travel between the process stations. A plurality of wafer carriers, each adapted to support a single wafer and be carried by the transport vehicles, are part of the system.