Patent attributes
A method for printing a periodic pattern of features into a photosensitive layer includes providing a mask bearing a periodic pattern, providing a substrate bearing the photosensitive layer, and arranging the substrate substantially parallel to the mask. A beam of collimated monochromatic light is formed for illuminating the mask pattern so that the light-field transmitted by the mask forms Talbot image planes separated by a Talbot distance. N sub-exposures of the mask with the beam are performed and the separation between sub-exposures are changed so that the relative separation during the ith sub-exposure with respect to that during the first sub-exposure is given by (mi+ni/N) times the Talbot distance. The mask pattern is exposed to the same energy density of illumination for each sub-exposure, wherein the period is selected in relation to the wavelength so that only the zeroth and first diffraction orders are transmitted by the mask.
