Fabrication of high-aspect ratio silicon nanopillars for tribological experiments

Abstract

© 2015 The Authors. This article reports the results of the fabrication of large arrays of nanopillars for future tribological experiments. This fabrication focused on achieving a constant high aspect ratio up to 1:24 and a separation between each pair of adjacent pillars. Electron beam lithography was used to write patterns in hydrogen silsesquioxane (HSQ) negative tone resist. To achieve nanopillars of high aspect ratios and with smooth sides, deep reactive ion etching was employed with SF6 and O2 at cryogenic temperatures. Finally, the residual HSQ was removed using CHF3/O2 plasma etching in order to obtain a smooth finish.