With an advance of fabrication technologies and computational electromagnetics the engineers can exploit very complex structures, which allow unprecedented control of electromagnetic fields over subwavelength spatial dimensions. Plasmonic nanostructures can focus light in very small dimensions, therefore they are applicable in unconventional photolithography to produce nanopatterns in a cost effective way, which are the required platform of several devices, e.g. very sensitive hydrogen sensors or very high density data storage devices.
In this Master Thesis bow-tie nanoantennas will be designed, which can be fabricated by self-assembling dielectric spheres on top of a photoresist layer, followed by metal deposition and removal of the spheres. The silver bow-tie nanoantennas, presented in Fig. 1, can focus light to expose the photoresist and to pattern very large areas of resist to fabricate periodic rod or hole structures arranged in hexagonal lattice.
The following tasks must be fulfilled:
- Literature review of the unconventional lithography setups.
- Execute numerical simulations to choose the geometry parameters and the constitutive materials. Calculate the electromagnetic intensity distribution of the nanoantennas in the photoresist.
- Investigate the applicability of the traditional dissolution models in case of unconventional nanolithography.
- Develop algorithm and produce software to calculate the resist pattern after dissolution.
- Optimize the parameters of the unconventional lithography setup and determine the parameters of the dissolution process to create holes with the smallest possible lattice constant at a given wavelength.