US Patent 7283255 Wireless substrate-like sensor

A wireless substrate-like sensor is provided to facilitate alignment and calibration of semiconductor processing systems. The wireless substrate-like sensor includes an optical image acquisition system that acquires one or more images of targets placed within the semiconductor processing system. Analysis of images of the targets obtained by the wireless substrate-like sensor provides position and/or orientation information in at least three degrees of freedom. An additional target is affixed to a known location within the semiconductor processing system such that imaging the reference position with the wireless substrate-like sensor allows the measurement and compensation for pick-up errors.