SUBSTRATE SUPPORT SYSTEM, LITHOGRAPHIC APPARATUS AND METHOD OF EXPOSING A SUBSTRATE

摘要

A substrate support system is provided, the substrate support system comprising: a support part, the support part configured to support a bottom surface of a substrate on a support plane; a moveable part, the moveable part moveable between a retracted position, in which a top end of the moveable part is below the support plane, and an extended position, in which the top end of the movcable part is above the support plane, such that the top end contacts the bottom surface of a substrate supported by the support part when moving between the retracted and extended positions and supports the bottom surface of the substrate above the support plane in the extended position; and a measurement system configured to measure a time taken for the moveable part to move from the retracted position to the extended position, to compare the measured time with a reference time, and to generate a signal when the measured time deviates from the reference time by more than a predetermined amount.