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Volume 6 Research & Reviews: Journal of Material Sciences
ISSN: 2321-6212 Materials Physics 2018
August 16-17, 2018
August 16-17, 2018 | London, UK
4th International Conference on
Condensed Matter and Materials Physics
Diamond growth in air at room temperature in СVD-grown pseudo-graphite films
I M Shmytko, O V Misochko and S K Brantov
Institute of Solid State Physics - RAS, Russia
Attempts have been made to develop a simple and fast technique of producing diamond-like films by chemical vapor
deposition (СVD) via methane pyrolysis at ~1270-1420 K using a simple reaction cell in the form of a capacitor. Under the
impact of electric field ~ 10-2 V/µm the сarbon condensed onto single crystal silicon substrates placed between the capacitor
graphite plates. However, applying this technique we obtained instead of diamond-like films, pseudo-graphite films with
graphitization index of ≈0.44. The films were extremely brittle, easily ground in an agate mortar into nanopowder with grain
sizes of several tens of nanometers and demonstrated micro hardness comparable to that of diamond (~70-90 GPа). They
also exhibited a pronounced texture in the direction of the film normal coinciding with the graphite c-axis and consisted of
nanocrystallites with average size <D>≈7 nm. Moreover, the films turned out to be highly inhomogeneous with local lattice
parameter variations Δc≈0.22 Ǻ (Δc/c≈ε=3.15%). After ~ 2 years this film aged in a normal atmosphere at room temperature
have undergone considerable and, in our opinion, unique variations. Researches on the film by XRD, Raman spectroscopy and
SEM methods showed that for the aging their structure has changed. The main products of the interaction of the films with
the atmosphere turned out to be carbide of silicon and carbon in the form of micro crystalline diamond of high perfection, see
fig.1-b. The mechanism reconstruction of pseudo-graphite film into the silicon carbide and diamond is discussed.
Res. Rev. J Mat. Sci. 2018, Volume 6
DOI: 10.4172/2321-6212-C2-018