Theoretical investigation of subwavelength structure fabrication based on multi-exposure surface plasmon interference lithography

Abstract

We propose a method of fabricating subwavelength structures based on multi-exposure surface plasmon interference lithography. This new nanolithography technique fabricates various subwavelength structures breaking the diffraction limit, which differs from the common method of writing various micro structures by using a two-laser-beam interference with sample rotation. Analysis of the optical field distributions obtained using the proposed nanolithography technique, which was performed using the theory of surface plasmon interference lithography in combination with coordinate matrix transformation, is also provided. Various special subwavelength structures are demonstrated by presenting simulated optical field distributions corresponding to different sample rotations, including two-dimensional lattice structures and periodic quasi-hexagonal structures. These structures are potentially useful in micro- and nano-optics applications. Keywords: Nanolithography, Subwavelength structures, Surface plasmon interference, Sample rotation