We report on the fabrication of two-dimensional arrays of nano-optical apertures in gold layers by electron beam lithography (EBL) on a transparent glass substrate. 30 x 30 μ m(2) large arrays of high aspect ratio sub-wavelength cylinders (400 nm diameter with period of 1.81 μ m) and annular apertures (diameters 250/330 nm and 3 10/330 nm inner/outer with period of 600 nm) were patterned in a 750 nm thick resist layer using a high contrast negative tone resist. The resist structures show sharp and vertical edges after development. The 150 nm thick deposited gold layer ensures optical transmission of less than 1.1 X 10(-4) at 633 nm wavelength. White light based optical characterizations agreed with theory predictions and prove the good quality of the structures.
Giulia Tagliabue, Alfredo Angelo Luigi Naef, Ershad Mohammadi, Theodoros Tsoulos
Jürgen Brugger, Roger Hersch, Thomas Walger