Patent ID: 8524443
Filing Date: 2013-09-03
Classification: G03B,G03F

Abstract:
1. A method for printing a desired periodic pattern of linear features into a photosensitive layer formed on a substrate, which method includes: a) providing a mask bearing a mask pattern of linear mask features that are parallel to a first direction, said linear mask features having a period that is twice that of the desired pattern; b) arranging the photosensitive layer parallel to the mask and with a separation from the mask pattern; c) generating monochromatic light at a wavelength; and d) illuminating the mask pattern with said light over a range of angles that lies substantially in a plane parallel to said first direction so that the light at each angle of illumination transmitted by the mask forms Talbot image planes and exposes the photosensitive layer to an angle-dependent transversal intensity distribution, whereby an integration of said distribution over the range of angles prints the desired periodic pattern; wherein the range of angles is selected in relation to the wavelength, the separation and the period such that illuminating the mask at an angle that is changed across the range would cause a particular transversal intensity distribution, which initially exposes the photosensitive laver, to displace longitudinally with respect to the layer by at least a distance between successive Talbot image planes that are formed by light at a mean angle of the range of angles.