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Title: Electrical conductivity of cluster-assembled carbon/titania nanocomposite films irradiated by highly focused vacuum ultraviolet photon beams

Abstract

We investigated the electrical transport properties of nanostructured carbon and carbon/titanium oxide nanocomposite films produced by supersonic cluster beam deposition and irradiated by highly focused vacuum UV photon beam. We have observed a relevant increase of the density of states at Fermi level, suggesting that the films acquire a 'metallic' character. This is confirmed by the increment of the conductivity of four orders of magnitude for pure nanostructured carbon films and at least eight orders of magnitude for films containing 9 at. % of titanium. A partial reversibility of the process is observed by exposing the modified films to molecular oxygen or directly to air. We demonstrate the capability of writing micrometric conductive strips (2-3 {mu}m width and 60 {mu}m length) and controlling the variation of the conductivity as a function of the titanium concentration.

Authors:
; ; ; ; ; ; ; ; ; ; ;  [1];  [2];  [2];  [3];  [2];  [2]
  1. CIMAINA-Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano (Italy)
  2. (Italy)
  3. (United Kingdom)
Publication Date:
OSTI Identifier:
20982774
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Applied Physics; Journal Volume: 101; Journal Issue: 6; Other Information: DOI: 10.1063/1.2437658; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; CARBON; CLUSTER BEAMS; COMPOSITE MATERIALS; DEPOSITION; ELECTRIC CONDUCTIVITY; FERMI LEVEL; IRRADIATION; NANOSTRUCTURES; OXYGEN; PHOTON BEAMS; THIN FILMS; TITANIUM; TITANIUM OXIDES; ULTRAVIOLET RADIATION

Citation Formats

Amati, M., Lenardi, C., Agostino, R. G., Caruso, T., Ducati, C., La Rosa, S., Bongiorno, G., Cassina, V., Podesta, P., Ravagnan, L., Piseri, P., Milani, P., CIMAINA-Istituto di Fisiologia Generale e Chimica Biologica, Universita di Milano, Via Trentacoste 2, I-20134 Milano, Dipartimento di Fisica, Universita della Calabria, Ponte Bucci, Cubo 33c, I-87036 Arcavacata di Rende, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ, Sincrotrone Trieste, S. S. 14 km 163.5, Area Science Park, I-34012 Basovizza-Trieste, and CIMAINA-Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano. Electrical conductivity of cluster-assembled carbon/titania nanocomposite films irradiated by highly focused vacuum ultraviolet photon beams. United States: N. p., 2007. Web. doi:10.1063/1.2437658.
Amati, M., Lenardi, C., Agostino, R. G., Caruso, T., Ducati, C., La Rosa, S., Bongiorno, G., Cassina, V., Podesta, P., Ravagnan, L., Piseri, P., Milani, P., CIMAINA-Istituto di Fisiologia Generale e Chimica Biologica, Universita di Milano, Via Trentacoste 2, I-20134 Milano, Dipartimento di Fisica, Universita della Calabria, Ponte Bucci, Cubo 33c, I-87036 Arcavacata di Rende, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ, Sincrotrone Trieste, S. S. 14 km 163.5, Area Science Park, I-34012 Basovizza-Trieste, & CIMAINA-Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano. Electrical conductivity of cluster-assembled carbon/titania nanocomposite films irradiated by highly focused vacuum ultraviolet photon beams. United States. doi:10.1063/1.2437658.
Amati, M., Lenardi, C., Agostino, R. G., Caruso, T., Ducati, C., La Rosa, S., Bongiorno, G., Cassina, V., Podesta, P., Ravagnan, L., Piseri, P., Milani, P., CIMAINA-Istituto di Fisiologia Generale e Chimica Biologica, Universita di Milano, Via Trentacoste 2, I-20134 Milano, Dipartimento di Fisica, Universita della Calabria, Ponte Bucci, Cubo 33c, I-87036 Arcavacata di Rende, Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ, Sincrotrone Trieste, S. S. 14 km 163.5, Area Science Park, I-34012 Basovizza-Trieste, and CIMAINA-Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano. Thu . "Electrical conductivity of cluster-assembled carbon/titania nanocomposite films irradiated by highly focused vacuum ultraviolet photon beams". United States. doi:10.1063/1.2437658.
@article{osti_20982774,
title = {Electrical conductivity of cluster-assembled carbon/titania nanocomposite films irradiated by highly focused vacuum ultraviolet photon beams},
author = {Amati, M. and Lenardi, C. and Agostino, R. G. and Caruso, T. and Ducati, C. and La Rosa, S. and Bongiorno, G. and Cassina, V. and Podesta, P. and Ravagnan, L. and Piseri, P. and Milani, P. and CIMAINA-Istituto di Fisiologia Generale e Chimica Biologica, Universita di Milano, Via Trentacoste 2, I-20134 Milano and Dipartimento di Fisica, Universita della Calabria, Ponte Bucci, Cubo 33c, I-87036 Arcavacata di Rende and Department of Materials Science and Metallurgy, University of Cambridge, Cambridge CB2 3QZ and Sincrotrone Trieste, S. S. 14 km 163.5, Area Science Park, I-34012 Basovizza-Trieste and CIMAINA-Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano},
abstractNote = {We investigated the electrical transport properties of nanostructured carbon and carbon/titanium oxide nanocomposite films produced by supersonic cluster beam deposition and irradiated by highly focused vacuum UV photon beam. We have observed a relevant increase of the density of states at Fermi level, suggesting that the films acquire a 'metallic' character. This is confirmed by the increment of the conductivity of four orders of magnitude for pure nanostructured carbon films and at least eight orders of magnitude for films containing 9 at. % of titanium. A partial reversibility of the process is observed by exposing the modified films to molecular oxygen or directly to air. We demonstrate the capability of writing micrometric conductive strips (2-3 {mu}m width and 60 {mu}m length) and controlling the variation of the conductivity as a function of the titanium concentration.},
doi = {10.1063/1.2437658},
journal = {Journal of Applied Physics},
number = 6,
volume = 101,
place = {United States},
year = {Thu Mar 15 00:00:00 EDT 2007},
month = {Thu Mar 15 00:00:00 EDT 2007}
}
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