Abstract: A robot arm comprises a first and a second link, the first link having a proximal end and a distal end and the second link having a proximal and a distal end. A fixed pulley, with circumferential surfaces concentric with the first pivot axis is mounted at the proximal end of the first link. A second-link pulley is fixed to the second link for rotation about the second pivot axis. An end effector pulley is fixed to the end effector for rotation about the third pivot axis. A first belt drive is also provided and includes one or more belts connected between the circumferential surfaces of the fixed pulley and the second link pulley so that ratation of the first link relative to the fixed pulley about the first pivot axis causes rotation of the second link about the second pivot axis relative to the first link. One or more idler pulleys is provided and is rotatably mounted to one or both of the links.

Abstract: The present invention is a wafer handling robot which does not require a second mechanism for performing the task of pre-alignment. The robot uses the moving elements of the wafer handling robot which perform the wafer handling tasks to perform the tasks of centering and notch or flat finding of a wafer.

Abstract: A wafer scrubbing system includes a upper and lower elongated scrubbers extending generally parallel with one another, the scrubbers being driven in rotation about their own axes. The wafer is disposed between the scrubbers so that the top and bottom surfaces of the wafer engage the scrubbers. The scrubbers are arranged to provide different frictional forces with the wafer at opposite ends of the scrubbers, and thereby provide a torque on the wafer about a central axis transverse to the top and bottom surfaces of the wafer and transverse to the scrubber axes.

Abstract: Wafer handling apparatus includes a plurality of holding stations arranged in an upstream-to-downstream order and devices to treat the wafers held at the stations. Cyclically operative wafer shifting devices engage the wafers, simultaneously remove the engaged wafers during that cycle from the holding stations, shift the engaged wafers downstream relative to said holding stations and then simultaneously redeposit the wafers onto the holding stations. Thus, each wafer redeposited on a cycle of the wafer shifting devices is disposed at a holding station downstream from the holding station occupied by such wafer before that cycle of the shifting devices. Wafer supply and removal devices are provided for introducing and removing the wafers to and from the holding stations after they are treated. A method of handling wafers among a plurality of holding stations is also disclosed.