Abstract: In synchrotron radiation (SR) proximity x-ray lithography (XRL), the image is formed under a partially coherent illumination condition. Typically the illumination system consists of one or more condenser mirrors that collect the radiation from a synchrotron source and provide a uniform illumination of the x- ray mask. For a non-ideal mirror surface, height irregularity might not be negligible compared to the wavelength of x ray. Although scattering from rough surfaces has been studied extensively, little attention has been given to the effect of partial coherent illumination. For proximity XRL, the angular blur of illumination as large as 2 - 4 mrad (3 $sigma@) has been proposed on the basis of modeling. The blur from the SR source alone is typically less than 1 mrad (3 $sigma@). In partially coherent illumination, we found that the roughness can add an extra amount of blur which is desirable. Roughness tolerance for XRL beamline mirrors is determined from this study. Finally, the influence of scattering on lithography image formation is discussed. !11
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