Single-spot e-beam lithography for defining large arrays of nano-holes

Efficient nanoscale patterning of large areas is required for sub-wavelength optics. Here we use the single-spot exposure strategy, where electron beam lithography (EBL) with a focused Gaussian beam is used to define shapes directly. The serial technique is optimized on the JEOL JBX-9500FS 100 keV prototype EBL system for speed and pattern fidelity to a minimum writing time of around 30 min/cm(2) for 200 nm periods in 2D lattices. The machine time and feasibility of the method are assessed in terms of the trade-off between high current and large writing field. (C) 2014 Elsevier B.V. All rights reserved.