A Raman study of diamond film growth on Co-cemented tungsten carbide

Journal Article · Tue Apr 01 04:00:00 EST 1997 · Journal of the Electrochemical Society

DOI:https://doi.org/10.1149/1.1837598· OSTI ID:509392

Polini, R; Traversa, E ^[1]; Marucci, A; Mattei, G ^[2]; Marcheselli, G ^[3]

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1. Univ. di Roma Tor Vergata (Italy). Dipt. di Scienze e Tecnologie Chimiche
2. CNR, Roma (Italy). Inst. di Metodologie Avanzate Inorganiche
3. Fabbrica Italiana Leghe Metalliche Sinterizzate S.p.A., Novara (Italy)

Phase purity and crystallinity of diamond films grown by hot filament chemical vapor deposition on ISO-grade K10 cemented carbide [94.2 wt % (w/o) WC-5.8 w/o Co] were studied by Raman spectroscopy as a function of substrate temperature, gas phase composition, and substrate pretreatments. High-quality diamond films were grown using 0.5% CH{sub 4}/H{sub 2} in a rather narrow range of substrate temperatures (750 to 760 C). In all the deposited coatings, the first-order Raman band of diamond is detected at 1337 cm{sup {minus}1}. This fact indicates that a 2 GPa residual compressive stress is present in the diamond phase. The linewidth of the diamond Raman peak increases with deposition temperature. This effect has been ascribed to a higher density of defects in diamond crystallites. It has been observed that Co removal from the substrate surface by wet chemical etching before deposition is less effective than a careful selection of deposition parameters to reduce the codeposition of nondiamond carbon phases. This finding has been attributed to the fast diffusion of the binder from the bulk to the substrate surface, even for the etched substrates.

• Sponsoring Organization: USDOE
• OSTI ID: 509392
• Journal Information: Journal of the Electrochemical Society, Journal Name: Journal of the Electrochemical Society Journal Issue: 4 Vol. 144; ISSN 0013-4651; ISSN JESOAN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CHEMICAL VAPOR DEPOSITION
COBALT
CRYSTAL GROWTH
CRYSTAL STRUCTURE
CUTTING TOOLS
DIAMONDS
HYDROGEN
METHANE
RAMAN SPECTROSCOPY
TUNGSTEN CARBIDES