Electronic Conduction Mechanisms of Self Assembled Monolayers of 7-Ethynyl-2,4,9-trithia-tricyclo[3.3.1.1$^{3,7}$]decane on Cadmium Sulfide

POSTER

Abstract

Four-terminal current-voltage (I-V) data are recorded for tunnel junctions of the type Al/barrier/Pb at temperatures ranging from 4K to room temperature. Conductance voltage (G-V) data are then derived numerically. The tunnel barrier is comprised of 7-Ethynyl-2,4,9-trithia-tricyclo[3.3.1.1$^{3,7}$]decane adsorbed on amorphous CdS ultra-thin films. The CdS films are of the order of 1-4 nm thick, and are prepared by RF sputtering in argon. 7ETTD is then spin-doped onto the CdS films from a dilute ($\sim $1.4 mg.ml$^{-1})$ solution in dimethylether which produces a self-assembled monolayer of the compound. Analysis of I-V, G-V and other data indicates that a combination of conduction mechanisms come into play depending on the current, voltage, and temperature. These mechanisms are primarily temperature activated hopping, direct tunneling, and, possibly, frontier-orbital coupling. The results show that the addition of a 7ETTD layer dramatically changes the electronic properties of the tunnel barrier. These changes are reflected in corresponding inelastic electron tunneling spectroscopy data.

Authors

  • Robert Mallik

  • Vishal Pandya

    Plasma Dynamics Corp., Department of Chemistry, University of Calabria, P. Bucci-15c, 87036 Rende (CS), ITALY, Air Force Institute of Technology, Gothenburg University, Sweden, Denison University, Department of Physics, University of Notre Dame, Department of Physics, John Carroll University, Department of Chemistry, The University of Akron, Department of Phyiscs, The University of Akron, Faculty of Chemical Technology, University of Pardubice, Czech Republic, Johns Hopkins University, Baltimore MD, Kent State University, Kent OH, University of Iowa, Physics Dept., Cleveland State University, Ohio State University, Rochester Institute of Technology, The Ohio State University, University of Akron, NASA Glenn Research Center, National Center For Space Exploration Research, Penn State College of Medicine, Department of Physics, Kent State University

  • Vishal Pandya

    Plasma Dynamics Corp., Department of Chemistry, University of Calabria, P. Bucci-15c, 87036 Rende (CS), ITALY, Air Force Institute of Technology, Gothenburg University, Sweden, Denison University, Department of Physics, University of Notre Dame, Department of Physics, John Carroll University, Department of Chemistry, The University of Akron, Department of Phyiscs, The University of Akron, Faculty of Chemical Technology, University of Pardubice, Czech Republic, Johns Hopkins University, Baltimore MD, Kent State University, Kent OH, University of Iowa, Physics Dept., Cleveland State University, Ohio State University, Rochester Institute of Technology, The Ohio State University, University of Akron, NASA Glenn Research Center, National Center For Space Exploration Research, Penn State College of Medicine, Department of Physics, Kent State University

  • Vishal Pandya

    Plasma Dynamics Corp., Department of Chemistry, University of Calabria, P. Bucci-15c, 87036 Rende (CS), ITALY, Air Force Institute of Technology, Gothenburg University, Sweden, Denison University, Department of Physics, University of Notre Dame, Department of Physics, John Carroll University, Department of Chemistry, The University of Akron, Department of Phyiscs, The University of Akron, Faculty of Chemical Technology, University of Pardubice, Czech Republic, Johns Hopkins University, Baltimore MD, Kent State University, Kent OH, University of Iowa, Physics Dept., Cleveland State University, Ohio State University, Rochester Institute of Technology, The Ohio State University, University of Akron, NASA Glenn Research Center, National Center For Space Exploration Research, Penn State College of Medicine, Department of Physics, Kent State University