procedures for registration by means of a projizierenden optical system belichtungsapparat for its implementation and the belichtungsapparat used semiconductor manufacturing process

摘要

A registration method is usable with a projection optical system (1) for projecting first and second patterns of a first object (1a) simultaneously upon a second object (2) having a surface step, for measuring at different locations the surface position of the second object with respect to the direction of optical axis of the projection optical system prior to the pattern projection to bring the surface of the second object into coincidence with an image plane of the projection optical system on the basis of the measurement, wherein the first pattern has a smaller depth of focus than that of the second pattern. The method includes bringing the surface position of the second object, at the location whereat the first pattern is to be projected, into coincidence with the image plane of the projection optical system; and correcting any tilt of the surface of the second object with respect to the image plane of the projection optical system. IMAGE