Digital writing of large diffraction grating patterns

Abstract

A method of fabricating a substrate includes providing a substrate having a flat surface and a beam writing system operable to write in a first direction and a second direction, wherein the second direction is perpendicular to the first direction, The method further includes providing a diffraction grating layout pattern having a first diffraction grating, a second diffraction grating, and a third diffraction grating. The method also includes locating the substrate in the beam writing system, whereby the beam writing system is operable to write into the flat surface, and aligning one of the first, second, and third diffraction gratings parallel with the beam writing system first direction. Additionally, the method includes writing the diffraction grating layout pattern into the substrate flat surface via the beam writing machine.