Y. G. Wang, M. X. Xia, B. S. Zou, T. H. Wang, W. Han, S. X. Zhou
Current-Voltage Characteristics of in Situ Graphitization of Hydrocarbon Coated on ZnSe Nanowire
Journal of Physical Chemistry C 114 (2010) 12839–12849
Current voltage characteristics of hydrocarbon coated on ZnSe nanowire annealed by current-induced Joule heating have been studied via an in situ transmission electron microscope (TEM) technique. The major feature of the measured current-voltage curves is the presence of negative conductance due to a remarkable drop of current at the early stage of the graphitization which decreases the density of the band tail states resulting from hydrogen that escaped from various clusters and the sp3 and sp2 coordinated carbon networks. At the later stage of graphitization, the current began to increase rapidly due to sp3 coordination transformation into sp2 coordination, which effectively narrowed the band gap. Finally, a linear relationship between the current and voltage appeared as a result of a phase transition from the amorphous hydrocarbon to graphite, leading to the semiconductor to conductor transition. The details revealed in the measured current-voltage curve strongly suggest that the electrical property of the hydrocarbon deposition may be optimized by intentional arrangement with current-induced Joule heating.
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Franta D., Nečas D., Zajíčková L., Buršíková V., Cobet C.,
Band structure of diamond-like carbon films assessed from optical measurements in wide spectral range,
Diamond and Related Materials 19 (2010) 114–122