SIX-DEGREE-OF-FREEDOM DISPLACEMENT MEASUREMENT METHOD FOR EXPOSURE REGION ON SILICON WAFER STAGE

摘要

A six-degree-of-freedom displacement measurement method for an exposure region (10) on a silicon wafer stage, applied in the six-degree-of-freedom displacement measurement of the exposure region (10) on the silicon wafer stage. The silicon wafer stage comprises a coil array (4) and a movement bench (3). A planar optical grating (9) is fixed below a magnetic steel array (8) of the movement bench (3). A reading head (5) is fixed in a gap of the coil array (4), and a central line of the reading head (5) coincides with a central line of a lens (1). A measurement region (11) is formed on the planar optical grating (9) by an incident measurement light beam (6) from the reading head (5), and the center of the measurement region (11) and the center of an exposure region (2) are located at a same vertical line. One part of the movement bench covered by the exposure region (2) is an approximately rigid body; and when the movement bench (3) is deformed due to movement or vibration, the reading head (5) measures the six-degree-of-freedom displacement of the exposure region, so that the six-degree-of-freedom displacement of the exposure region (2) is obtained by means of calculation. In the method, the six-degree-of-freedom displacement of the exposure region (2) at any time during the movement of the silicon wafer stage is measured; the measurement complexity is reduced and the measurement precision is improved, and especially, the six-degree-of-freedom displacement of the exposure region (2) can at any time be precisely measured even if the movement bench (3) has high flexibility.