| 摘要 |
PURPOSE:To realize the optimum focusing for the size of an exposure region and each device, at the time of wafer exposure. CONSTITUTION:A plurality of focusing positions 31 selected for each device are designated in the exposure region 32 of a wafer, and the vertical position is detected at each focusing position 31. Thereby the focusing of the exposure regions 32 concerning a reduction projection lens is performed. The focusing positions 31 are determined at five points on each scribe line on four corners of the exposure region 32 different in devices and in the vicinity of the central part. The height difference between the scribe lines and the pattern forming surface is equal at the focusing points 31 of each exposure region 32, so that the vertical position can be accurately detected. In spite of difference of the sizes of the exposure regions 32 and the kinds of devices, the optimum focusing is enabled, and a stable pattern can be formed. As to the position where the focusing positions 31 overlap with each other between the exposure regions 32, focusing capability can be improved by preserving the previously detected vertical position data. |
