Ulster University Logo

Ulster Institutional Repository

Investigation of local ordering and electronic structure in Si- and hydrogen-doped tetrahedral amorphous carbon thin films

Biomedical Sciences Research Institute Computer Science Research Institute Environmental Sciences Research Institute Nanotechnology & Advanced Materials Research Institute

Abbas, GA, Papakonstantinou, P and McLaughlin, JAD (2005) Investigation of local ordering and electronic structure in Si- and hydrogen-doped tetrahedral amorphous carbon thin films. APPLIED PHYSICS LETTERS, 87 (25). p. 251918. [Journal article]

[img]PDF - Published Version
170Kb

URL: http://scitation.aip.org/getpdf/servlet/GetPDFServlet?filetype=pdf&id=APPLAB000087000025251918000001&idtype=cvips&prog=normal

DOI: 10.1063/1.2149173

Abstract

This work investigates the C K-edge near-edge x-ray absorption fine structure (NEXAFS) and x-ray reflectivity spectra of Si- and hydrogen-incorporated tetrahedral amorphous carbon (ta-C:Si:H) films. The C K-edge NEXAFS spectra indicate that the sp(2)/sp(3) hybridization ratio increases with the amount of tetramethylsilane vapor precursor introduced during deposition. This suggests that Si addition enhances sp(2)- and reduces sp(3)-bonding configurations. The increase in sp(2) sites correlates well with the decrease in hardness, mass density, and thermal stability. The comparison of angle-dependent NEXAFS spectra of nondoped and Si-doped ta-C films at the K edge reveals significantdopant-induced local ordering in pi(C = C)(*) and sigma(C-H)(*) orbitals. In contrast to the highly oriented pyrolytic graphite, the pi(C = C)(*) orbitals lie parallel to the surface. (c) 2005 American Institute of Physics.

Item Type:Journal article
Faculties and Schools:Faculty of Computing & Engineering
Faculty of Computing & Engineering > School of Engineering
Research Institutes and Groups:Engineering Research Institute
Engineering Research Institute > Nanotechnology & Integrated BioEngineering Centre (NIBEC)
ID Code:280
Deposited By:Mrs Ann Blair
Deposited On:19 Oct 2009 13:07
Last Modified:05 Mar 2012 15:58

Repository Staff Only: item control page