An imaging technique using TM polarized illumination at 45 degree incidence to a highly reflective surface has been demonstrated possible. The imaging technique was able to produce a single row of over exposed nanochannels. Further experimentation will be required to develop a stable process where multiple rows of channels can be formed. Once the optimal process is determine, experimentation can be designed to create either or both photonic crystal structures and a pitch doubling technique.
"Three Dimensional Nanochannel Formation by Reflective Interference Lithography,"
Journal of the Microelectronic Engineering Conference: Vol. 17
, Article 9.
Available at: https://scholarworks.rit.edu/ritamec/vol17/iss1/9