| 摘要 |
In view of a specific area having a characteristic surface state in a mark-formed area or a surrounding area thereof, an area calculation unit (33) has a window having a dimension corresponding to the specific area scan the whole measurement area in order to obtain a quantity representing a surface state based on measured signals through the window, and then, by identifying a measured signal area corresponding to the specific area based on the quantity as a function of the window's position, extracts a measured signal area corresponding to the mark. And a position calculation unit (35) performs computation such as pattern-matching on the signal area extracted, thereby detecting the position of the mark accurately and quickly. <IMAGE> |
