| 摘要 |
PURPOSE:To enable optimum exposure and improve exposure precision, by calculating the surface shape of the whole surface of a substrate to be exposed before exposure, performing AF detection for each shot at the time of step-and- repeat exposure, determining the optimum exposure plane on the basis of the Af detection and the surface shape, and performing exposure by making the optimum exposure plane coincide with in ideal exposure plane. CONSTITUTION:By moving a wafer stage 24, a global AF measuring shot on a wafer 1 is moved to an AF measuring position, and the position, in the direction of an optical axis, of the surface of a substrate 1 to be exposed in a plurality of shots is detected before exposure. On the basis of all stored AF measurement data, the surface shape of the whole surface of the wafer 1 is calculated and grasped. For each shot the AF measurement similar to the one performed about one of the above-mentioned AF measuring shots is performed. The optimum exposure plane of each shot is determined by the AF measurement values and the above grasped surface shape. By performing correction driving of X, Y, and theta for making the optimum exposure plane coincide with an ideal exposure plane, the alignment of a mask 8 and the wafer 1 in the plane direction is performed, and the exposure of present shot is performed. |
