US Patent 11380578 Formation of angled gratings

Systems and methods discussed herein can be used to form gratings at various slant angles across a grating material on a single substrate by determining an ion beam angle and changing the angle of an ion beam among and between ion beam angles to form gratings with varying angles and cross-sectional geometries. The substrate can be rotated around a central axis, and one or more process parameters, such as a duty cycle of the ion beam, can be modulated to form a grating with a depth gradient.