Fabrication of silicon nanospheres placeable on a desired position for dielectric metamaterials in the visible region

Abstract

We proposed a fabrication method for silicon nanospheres with diameters of 100-200 nm at arbitrary locations by using electron-beam lithography and hydrogen annealing. The nanospheres showed a strong magnetic field response in the visible region that was observed as scattered light emitted from the nanospheres. The scattering spectra were calculated by finite-difference time-domain simulation. Periodically arranged silicon nanospheres were successfully fabricated as designed, and the scattered light was measured by dark-field illumination microscopy. The scattering spectra were in the visible range, and the peak position was redshifted as the diameter increased.