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1. A system comprising: a semiconductor processing tool including: a wafer-handling robot; one or more wafer stations; and a first controller, wherein: each wafer station includes one or more corresponding wafer supports, the wafer-handling robot and the first controller are communicatively connected; and an autocalibration wafer including: a substrate sized to be carried by the wafer-handling robot and having a first side that is configured to contact an end effector of the wafer-handling robot when the substrate is carried by the wafer-handling robot; a plurality of first imaging sensors supported by the substrate and positioned at locations offset from a common point of the substrate, each first imaging sensor having a downward-facing field of view when the substrate is oriented with the first side facing downwards; and a second controller, wherein: the second controller is communicatively connected with each of the first imaging sensors, and the second controller and the first controller, in aggregate, are configured to: a) select a first wafer support of the one or more wafer supports of a first wafer station of the one or more wafer stations, b) cause the wafer-handling robot to position the autocalibration wafer above the first wafer station, c) cause each first imaging sensor to obtain a corresponding first image of a fiducial of the first wafer support while the autocalibration wafer is positioned above the first wafer support, d) cause the wafer-handling robot to retrieve a first edge ring, e) cause the wafer-handling robot to transfer the first edge ring to the first wafer support such that a center point of the first edge ring is nominally centered on a center point of the first wafer support when viewed along a vertical axis, f) cause the wafer-handling robot to position the autocalibration wafer over the first wafer support and the first edge ring, g) cause each first imaging sensor to obtain a corresponding second image of a fiducial of the first wafer support and a fiducial of the first edge ring while the autocalibration wafer is positioned over the first wafer support and the first edge ring, and h) determine an edge ring/wafer support horizontal offset between the center point of the first edge ring and the center point of the first wafer support based on gap sizes between the fiducials of the first wafer support and the first edge ring in the second images.
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