Full Minimum Feature Size Enforcement Toward Freeform Optical Metasurfaces at Wafer-Scale

Optical metasurfaces are an exciting area of research and development because they have demonstrated massive size and weight reduction when compared with conventional optical systems. At the same time, high-volume lithographic processes, which are necessary for bringing such systems out of the research lab and into general use, constrain the feature sizes which can be produced. This reality is especially important for the design of devices operating in the optical regime. In this paper, we share our recent work which provides a concrete set of criteria for checking the satisfaction of a minimum feature size (MFS) rule, and from this derive a method for MFS enforcement on lithographic masks for both filled and void regions. Using this method we are able to demonstrate a performance horizon associated with the MFS relative to the operating wavelength, bounding the performance achievable through device optimization.