ISSN:
1662-0356
Source:
Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
Topics:
Natural Sciences in General
,
Technology
Notes:
The physical properties of graphene nano-structures are highly anisotropic and generallycorrelated to the graphene sheet orientation. We investigated the capability to grow nano-graphenestructured carbon films and to control their texturing by pulsed laser ablation of a pyrolyticgraphite target (Nd:YAG laser, 2nd harmonic: λ=532 nm, hν=2.33 eV, τ=7 ns, ν=10 Hz, φ=7J/cm2), operating at different temperature conditions. Carbon films were deposited on Si 〈100〉substrates. Detailed characterisation by synchrotron X-ray measurements were performed onsamples deposited in vacuum (~10-3 Pa) at high substrate temperatures (〉800°C) and at roomtemperature followed by post-annealing at high temperature (〉800°C). The X-ray measurementsestablished the formation of nano-sized graphene structures for both sample sets. In the first set, thenano-particles are correlated among them, their size increases with substrate temperature and alongitudinal growth of parallel graphene layers occurs, with the ˆc axis parallel to the substrate. Inpost annealed sample set, on the contrary, the nano-particles size is smaller and depends weakly onannealing temperature. The graphene ˆc axis results to be randomly oriented up to ~850°C. Abovethis temperature it seems that a transition phase occurs and the c axis results to lie parallel tosubstrate plane
Type of Medium:
Electronic Resource
URL:
http://www.tib-hannover.de/fulltexts/2011/0528/01/42/transtech_doi~10.4028%252Fwww.scientific.net%252FAST.48.55.pdf
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