US Patent 8215262 Cluster tool architecture for processing a substrate

Embodiments generally provide an apparatus and method for processing substrates using a multi-chamber processing system (e.g., a cluster tool) that has an increased system throughput, increased system reliability, substrates processed in the cluster tool have a more repeatable wafer history, and also the cluster tool has a smaller system footprint. In one embodiment, a cluster tool for processing a substrate includes a first processing rack, a first robot assembly and a second robot assembly operable to transfer substrates to substrate processing chambers in the first processing rack, and a horizontal motion assembly. The horizontal motion assembly includes one or more walls that form an interior region in which a motor is enclosed. The one or more walls defining an elongated opening through which a robot support interface travels, the robot support interface supporting a robot of the horizontal motion assembly.