Three-dimensional photonic crystals have stimulated researchers in fundamental photonics, as well as possible applications in optical transistors, computers and other devices. However fabricating these structures with the required alignment between different planes has proved fiendishly challenging. A group in the Netherlands has shown that patterning a planar mask to project correctly onto two perpendicular surfaces simultaneously can produce the desired preliminary patterns for etching aligned 3D structures……
http://nanotechweb.org/cws/article/tech/63376
