US Patent 7727410 Process for formation of three-dimensional photonic crystal

A process for forming a three-dimensional photonic crystal comprises the steps of providing a base material having a first face and a second face adjoining to each other at a first angle, forming a first mask on the first face, dry-etching the first face in a direction at a second angle to the first face to remove a portion of the base material not protected by the first mask, forming a second mask on the second face, and dry-etching the second face in a direction at a third angle to the second face to remove a portion of the base material not protected by the second mask.