Growth of nanostructured CuO thin films via microplasma-assisted, reactive chemical vapor deposition at high pressures

A variety of nanostructured CuO thin films composed of vertically-aligned wires, needles, leaves, trees, and fans were grown using DC microplasma jets at high pressure (similar to 10 Torr) under oxidizing conditions. A directed flux of active Cu species (atoms, metastables, etc.) for growth was created through dissociation of an organometallic Cu precursor in the hollow-cathode region of a flow-stabilized microplasma, followed by entrainment of species in the expanding, supersonic gas jet. Phase-pure CuO films were spray-deposited onto Si and ITO using both static and raster-scanned jet configurations with growth rates as high as several nm/s. The effects of background gas atmosphere, precursor flux, deposition time, substrate scanning speed, and substrate temperature on CuO film morphology and growth rate are discussed. (C) 2012 Elsevier B.V. All rights reserved.