Search: L773:0040 6090 OR L773:1879 2731
> (2000-2009) >
Chemical vapour dep...
Chemical vapour deposition of molybdenum carbides: aspects of phase stability
-
- Lu, J (author)
- Department of Inorganic Chemistry, Ångström Laboratory, University of Uppsala, Box 538, S-751 21 Uppsala, Sweden
-
- Hugosson, Håkan Wilhelm, 1972- (author)
- Condensed Matter Theory Group, Department of Physics, University of Uppsala, Box 530, S-751 21, Uppsala, Sweden
-
- Eriksson, O (author)
- Condensed Matter Theory Group, Department of Physics, University of Uppsala, Box 530, S-751 21, Uppsala, Sweden
-
show more...
-
- Nordström, L (author)
- Condensed Matter Theory Group, Department of Physics, University of Uppsala, Box 530, S-751 21, Uppsala, Sweden
-
- Jansson, U (author)
- Department of Inorganic Chemistry, Ångström Laboratory, University of Uppsala, Box 538, S-751 21 Uppsala, Sweden
-
show less...
-
(creator_code:org_t)
- Elsevier, 2000
- 2000
- English.
-
In: Thin Solid Films. - : Elsevier. - 0040-6090 .- 1879-2731. ; 370:1-2, s. 203-212
- Related links:
-
https://urn.kb.se/re...
-
show more...
-
https://doi.org/10.1...
-
show less...
Abstract
Subject headings
Close
- Thin films of different molybdenum carbides (δ-MoC1−x, γ′-MoC1−x and Mo2C) have been deposited from a gas mixture of MoCl5/H2/C2H4 at 800°C by CVD. The H2 content in the vapour has a strong influence on the phase composition and microstructure. Typically, high H2 contents lead to the formation of nanocrystalline δ-MoC1−x films while coarse-grained γ′-MoC1−x is formed with an H2-free gas mixture. This phase has previously only been synthesized by carburization of Mo in a CO atmosphere and it has therefore been considered as an oxycarbide phase stabilized by the presence of oxygen in the lattice. Our results, however, show that γ′-MoC1−x films containing only trace amounts of oxygen can be deposited by CVD. Stability calculations using a FP-LMTO method confirmed that the γ′-MoC1−x phase is stabilized by oxygen but that the difference in energy between e.g. δ-MoC0.75 and oxygen-free γ′-MoC0.75 is small enough to allow the synthesis of the latter phase in the absence of kinetic constraints. Annealing experiments of metastable δ-MoC1−x and γ′-MoC1−x films showed two different reaction products suggesting that kinetic effects play an important role in the decomposition of these phases.
Subject headings
- NATURVETENSKAP -- Fysik (hsv//swe)
- NATURAL SCIENCES -- Physical Sciences (hsv//eng)
Keyword
- Molybdenum carbide
- Carbides
- Chemical vapor deposition
Publication and Content Type
- ref (subject category)
- art (subject category)
Find in a library
To the university's database