AVS 57th International Symposium & Exhibition
    Nanometer-scale Science and Technology Wednesday Sessions
       Session NS+EM+EN-WeA

Paper NS+EM+EN-WeA10
20 μs Photocurrent Response from Lithographically Patterned Nanocrystalline Cadmium Selenide Nanowires

Wednesday, October 20, 2010, 5:00 pm, Room La Cienega

Session: Photonic and Plasmonic Materials and Devices
Presenter: S.-C. Kung, University of California, Irvine
Authors: S.-C. Kung, University of California, Irvine
W.E. van der Veer, University of California, Irvine
F. Yang, University of California, Irvine
K.C. Donavan, University of California, Irvine
R.M. Penner, University of California, Irvine
Correspondent: Click to Email
Lithographically patterned nanowire electrodeposition (LPNE) provides a method for patterning nanowires composed of nanocrystalline cadmium selenide (nc-CdSe) over wafer-scale areas. We assess the properties of (nc-CdSe) nanowires for detecting light as photoconductors. Structural characterization of these nanowires by X-ray diffraction and transmission electron microscopy reveals they are composed of stoichiometric, single phase, cubic CdSe with a mean grain diameter of 10 nm. For nc-CdSe nanowires with lengths of many millimeters, the width and height dimensions could be varied over the range from 60 to 350 nm (w) and 20 to 80 nm (h). Optical absorption and photoluminescence spectra for nc-CdSe nanowires were both dominated by band-edge transitions. The photoconductivity properties of nc-CdSe nanowire arrays containing ~350 nanowires were evaluated by electrically isolating 5 μm nanowire lengths using evaporated gold electrodes. Photocurrents, iphoto, of 10-100× (idark) were observed with a spectral response characterized by an onset at 1.75 eV. iphoto response and recovery times were virtually identical and in the range from 20 to 40 μs for 60 × 200 nm nanowires.