Exposure method based on multiple exposure process
AssigneeCanon Kabushiki Kaisha
InventorYumiko Ohsaki
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Abstract
An exposure method for printing, upon a photosensitive material, a pattern having fine lines of an odd number extending about a certain point, through a multiple exposure process, wherein a phase shift mask having an even number of boundaries defined with a phase difference of 180 deg. between adjacent regions about the point, is used, and wherein the number of the boundaries is larger than the number of fine lines.
Claims16
An exposure method for printing, upon a photosensitive material, a pattern having fine lines of an odd number extending about a certain point, through a multiple exposure process, characterized in that a phase shift mask having an even number of boundaries defined with a phase difference of 180 deg. between adjacent regions about the point, is used, wherein the number of the boundaries is larger than the number of fine lines.
A multiple exposure method using plural masks, characterized in that a position where an image of a low-contrast pattern is to be formed on the basis of a mask, of the masks, having fine lines extending in different directions, is exposed with an image of a pattern of a mask having a phase difference of 180 deg. between adjacent patterns, whereby a contrast of an exposure amount distribution related to the pattern of the low contrast is increased.
Dependencies are inferred from the claim text.