| 摘要 |
PURPOSE:To make it possible to prevent the generation of alignment errors such as impossibility of autoalignment and an alignment mark erroneous recognition by a method wherein the scanning direction of a scanning head is set in two crossing directions. CONSTITUTION:In a wafer alignment method with which a wafer 20 and a reticle or a mask are aligned by scanning the wafer alignment mark 2 provided on the surface of the wafer 20 and also by detecting a scattered light on the alignment mark, the scanning direction of the above-mentioned scanning head is set in two intersecting directions. For example, the laser beam 1 coming from a laser tube 11 is sent to a vertical scanning mirror 16 or a horizontal scanning mirror 17 by an optical path switching mirror 12 through the intermediary of mirrors 13 to 15, and the alignment mark 2 is scanned in vertical direction or in horizontal direction. At that time, the scattered light 5 is detected from the mark by a photoelectric conversion sensor 18, and the alignment mark is discriminated from the waveform of the scattered light. |
