Multiexposure laser interference lithography

Nanopatterns resulting from two-beam interference in single, double, and multiexposures were simulated. Several patterns were experimentally fabricated to compare with the simulated patterns, allowing judgment of the quality of the simulation tool. Experimental and simulation results were consistent for single and double exposures. Photoresist nanofibers attached and detached from the substrate were fabricated with few changes in the development process. Results show that by increasing the number of exposures, a wide variety of patterns with very fine structures and sophisticated geometries can be generated. Fresnel-lens type structures are formed when the number of exposures is increased. These Fresnel-like patterns might have potential use in obtaining radial and azimuthal polarizations and optical vortices in addition to areas such as security patterns and diffractive optical elements.