Plasmonic interference nanolithography with a double-layer planar silver lens structure.

We present here a surface plasmon interference lithography method with double-layer planar silver lens. This kind of lithography method provides interference patterns with sufficient contrast for lithography process and simple structure for the convenience of fabrication. Rigorous coupled wave analysis method has been performed with practical parameters to testify this lithography scheme. Furthermore, some key factors influencing the pattern quality have been discussed. It is pointed out that three factors mainly determine the resolution of the interference patterns, and therefore we give a theoretical resolution limit of about 1/12 wavelength to the surface plasmon interference lithography method.