Nitrogen self-diffusion in magnetron sputtered Si-C-N films

Journal Article · Sun May 01 00:00:00 EDT 2011 · Journal of Applied Physics

DOI:https://doi.org/10.1063/1.3585780· OSTI ID:21560227

Hueger, E; Schmidt, H ^[1]; Geue, T; Stahn, J ^[2]; Tietze, U; Lott, D ^[3]; Markwitz, A ^[4]; Geckle, U; Bruns, M ^[5]

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1. Institute of Metallurgy, Materials Physics Group, Clausthal University of Technology, Robert-Koch-Str. 42, D-38678 Clausthal-Zellerfeld (Germany)
2. Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)
3. Helmholtz-Zentrum Geesthacht, Max Planck Str. 1, D-21502 Geesthacht (Germany)
4. National Isotope Centre, GNS Science, 30 Gracefield Road, PO Box 31-312 Lower Hutt (New Zealand)
5. Institute for Materials Research III, Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen (Germany)

Self-diffusion was studied in magnetron sputtered nitrogen-rich amorphous compounds of the system Si-C-N by using nitrogen as a model tracer. As shown by infra-red spectroscopy a transient metastable region exists, where the structure of the material can be visualized as silicon nitride tetrahedra which are connected by carbo-diimide (-N=C=N-) bonds to a three dimensional amorphous network. In this region diffusion studies are carried out by neutron reflectometry and isotope multilayers as a function of annealing time, temperature and chemical composition. Low diffusivities between 10{sup -20} and 10{sup -24} m{sup 2}/s were found. In the metastable region, diffusion is faster than diffusion in amorphous silicon nitride by 1 to 2 orders of magnitude, while the activation enthalpies of diffusion between 3.1 and 3.4 eV are the same within error limits. This can be explained by the fact that the diffusion mechanism along SiN{sub 4} tetrahedra is identical to that in amorphous silicon nitride, however, the carbo-diimide bonds seem to widen the structure, allowing faster diffusion. A correlation between diffusivities and the number of carbo-diimid bonds present in the material is found, where the highest diffusivities are observed for materials with the highest number of carbo-diimid bonds, close to the composition Si{sub 2}CN{sub 4}.

• OSTI ID: 21560227
• Journal Information: Journal of Applied Physics, Vol. 109, Issue 9; Other Information: DOI: 10.1063/1.3585780; (c) 2011 American Institute of Physics; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
AMORPHOUS STATE
ANNEALING
CARBON COMPOUNDS
CHEMICAL BONDS
CHEMICAL COMPOSITION
DEPOSITION
INFRARED SPECTRA
LAYERS
MAGNETRONS
NITROGEN
NITROGEN COMPOUNDS
SELF-DIFFUSION
SEMICONDUCTOR MATERIALS
SILICON COMPOUNDS
SPECTROSCOPY
SPUTTERING
TEMPERATURE DEPENDENCE
THIN FILMS
DIFFUSION
ELECTRON TUBES
ELECTRONIC EQUIPMENT
ELEMENTS
EQUIPMENT
FILMS
HEAT TREATMENTS
MATERIALS
MICROWAVE EQUIPMENT
MICROWAVE TUBES
NONMETALS
SPECTRA