Nanofabrication on bumpy or multilevel surfaces is often a problem; even for the most accurate state-of-the-art methods. Now, reporting in Nanotechnology, researchers at Aalto University in Finland have established a rapid fabrication process that may provide a solution. They utilize atomic layer deposition (ALD) of ion-sensitive resist for the very conformal coating of non-planar sample surfaces. The key feature is the exposure of patterns by focussed ion beam (FIB), which has a large depth of focus in comparison to e-beam or UV lithographies.
The application of ALD and FIB effectively solves the problems with resist deposition and exposure. The difficulties associated with non-uniform etching speed are addressed by solely utilizing dry etching for both the resist development and release etching steps.
Full story: http://nanotechweb.org/cws/article/lab/57900