Edge roller assembly, method for contacting an edge of a substrate, and transport system for transporting semiconductor wafers to a wafer processing station

The present invention relates generally to semiconductor fabrication and, more particularly, to an edge roller assembly, a method for contacting an edge of a substrate, and a transport system for transporting semiconductor wafers to a wafer processing station. An edge roller assembly includes first and second grip rings. The grip rings are held together in an opposing relationship such that outer surfaces thereof define a groove for receiving an edge of a substrate. The grip rings may be O-rings formed of a rubber material. In one embodiment, the grip rings are held together by lower and upper clamp plates that are adjustably fastened together so that the clamping forces exerted on the substrate can be controlled. The upper clamp plate may have a height adjustment knob for adjusting the height of the edge roller assembly mounted thereon. A method for contacting an edge of a substrate and a transport system for transporting semiconductor wafers to a wafer processing station also are described.