| 摘要 |
PURPOSE:To expand a focus margin and to enhance the throughput of the title exposure method by a method wherein the exposure amount near a center focus is sensed relatively and the movement speed in the Z-axis direction of a member which moves an image formation face is changed. CONSTITUTION:A wafer stage 7 at a projection aligner is constituted of the following: an X-Y stage 8 which moves a wafer 10 in its inner-face direction (X-Y direction); and a Z stage 9 which moves the wafer in the optical-axis (Z-axis) direction. When the action of the stage 8 is combined with that of the stage 9, the wafer 10 is moved to a designated position. The stage 9 is raised or lowered in the optical-axis direction; a three-stage image-formation face is set; an exposure operation is performed sequentially. In this case, the exposure amount of a center focus [indicated by a solid line (b)] is divided partially into the side of a minum focus [indicated by a solid line (a)] and the side of a plus focus [indicated by a solid line (c)]. Thereby, a wide margin is obtained in a composed light-intensity contrast curve [indicated by a broken line (d)], and the throughput of the title exposure method can be enhanced when the ascending and descending speed of the stage 9 is made relatively large near the center focus. |
