title: Microplasma-based synthesis of vertically aligned metal oxide nanostructures.
abstract: Vertically aligned metal oxide nanostructures (e.g., wires, needles, pillars and trees) of CuO, PdO and NiO were synthesized on several substrates (e.g., Si and ITO (indium tin oxide)) using a high-pressure (~Torr) microplasma-based growth technique. Organometallic precursors were dissociated in the hollow cathode region of a supersonic plasma jet creating a directed flux of metal species (e.g., atoms, metastables, etc) which react with an oxygen background to form crystalline metal oxide films having a variety of nanomorphologies. Spiral-like growth fronts were seen in some cases for CuO, suggesting that nanowire growth may involve screw dislocations. Large area, nanowire films >1 cm(2) with good adhesion and electrical connection to ITO substrates were deposited by raster-scanning a single jet. Details of the microplasma operation, the dynamics of the growth process and the resulting materials are discussed.
authors.affiliation: Department of Chemical Engineering, University of California Santa Barbara, Santa Barbara, CA 93106-5080, USA.
authors.forename: Travis L
authors.initials: TL
authors.lastname: Koh
authors.forename: Evan C
authors.initials: EC
authors.lastname: O'Hara
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Gordon