Patent ID: 6727979
Filing Date: 2004-04-27
Classification: G03B

Abstract:
A projection aligner for transferring an image of a pattern formed on a mask to an object to be exposed by scanning a light beam across the mask and the object, said projection aligner comprising:a projection optical system that projects the light beam passed through the mask onto the object; a magnification adjusting mechanism that adjusts the magnification of said projection optical system; a driving mechanism that moves the mask and the object synchronously so that the light beam scans across the mask and the object in a predetermined beam scanning direction; and a controller that controls said magnification adjusting mechanism and said driving mechanism to keep a difference between the magnification of said projection optical system and a velocity ratio of the mask and the object moved by said driving mechanism below a predetermined maximum value, said maximum value being determine based on a line width of the pattern formed on the mask.