Fabrication of diamond nanopillars and their arrays

High-density, uniform diamond nanopillar arrays were fabricated by employing bias-assisted reactive ion etching in a hydrogen/argon plasma. Gold nanodots were employed as etching masks. The formation of nanopillar structure is associated with the directional physical etching/sputtering by ion bombardment and selective chemical etching of s p2 carbons by reactive hydrogen atoms and ions. The density and geometry of the nanopillars depend on the initial structure of diamond films and reactive ion etching conditions. The nanopillars with high aspect ratio and large surface area may have potential applications in high-efficiency and high-sensitivity diamond-based biomedical and chemical sensors and in mechanical and thermal management. © 2008 American Institute of Physics.