title: Fabrication of Sub-25 nm Diameter GaSb Nanopillar Arrays by Nanoscale Self-Mask Effect.
abstract: GaSb individual nanowires and nanowire arrays are considered as intriguing candidates for electronic and photonic applications. In this paper, we report a new mask-free method to fabricate large area GaSb nanopillar arrays through reactive ion etching of GaSb substrates facilitated by O2 plasma. We have shown that nanoscale oxide self-masks could form thereby facilitating the formation of GaSb nanopillars. We have achieved GaSb nanowires with diameters less than 25 nm and an aspect ratio of 24. Additionally, GaSb nanopillar arrays with desired heights, diameters, and density can be obtained by choosing the plasma chemistry and/or controlling etching parameters, such as bias power and pressure. The nanopillar arrays prepared also exhibit tunable broadband antireflection properties.
authors.affiliation: †Department of Physics and Astronomy, §Weldon School of Biomedical Engineering, and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Tzuging
authors.initials: T
authors.lastname: Lin
authors.affiliation: †Department of Physics and Astronomy, §Weldon School of Biomedical Engineering, and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Sarath
authors.initials: S
authors.lastname: Ramadurgam
authors.affiliation: †Department of Physics and Astronomy, §Weldon School of Biomedical Engineering, and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Chien-Sheng
authors.initials: CS
authors.lastname: Liao
authors.affiliation: †Department of Physics and Astronomy, §Weldon School of Biomedical Engineering, and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Yunlong
authors.initials: Y
authors.lastname: Zi
authors.affiliation: †Department of Physics and Astronomy, §Weldon School of Biomedical Engineering, and ‡Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
authors.forename: Chen
authors.initials: C
authors.lastname: Yang
keywords: GaSb; Nanowires; antireflection coatings; reactive ion etching