Stage control apparatus, exposure apparatus and method of manufacturing a semiconductor device

摘要

An exposure apparatus includes a projection optical system for projecting exposure light, with which a reticle formed with a pattern is irradiated, onto a wafer, a stage for holding and aligning the wafer or reticle, an alignment optical system for outputting alignment light, a reflection mirror provided on the stage, and a plurality of interferometers for measuring the position of the stage by irradiating the reflection mirror with measurement light. The interferometer to be used to measure the position of the stage in a predetermined direction is switched to another in accordance with whether the stage is aligned to the projection optical system or to the alignment optical system. <IMAGE>