CPC G03F 7/001 (2013.01) [B05C 3/02 (2013.01); B05D 1/18 (2013.01); B81C 1/00523 (2013.01); B81C 1/00539 (2013.01); B81C 1/00555 (2013.01); B81C 1/00626 (2013.01); B81C 1/00634 (2013.01); G02B 5/1857 (2013.01)] | 18 Claims |
1. A method of etching a blazed surface relief structure in a substrate, the method comprising:
moving the substrate between a first position and a second position in an etching system, wherein in the first position only a first part of the area to be etched is exposed to an etchant, wherein the etchant is an anisotropic etchant, and in the second position the area to be etched is exposed to the etchant such that the first part of the area to be etched is exposed to the etchant for a longer period of time than at least one other part of the area to be etched, and wherein the movement is defined according to an etching profile, both the movement of the substrate and an orientation of the substrate are relative to a surface of the etchant defined according to the etching profile; and
removing the substrate from the etchant when etching is complete;
wherein the surface relief structure comprises a variable depth etching profile.
|