Cavity ring-down spectroscopy measurements of the concentrations of C 2(X1Σg +) radicals in a DC arc jet reactor used for chemical vapour deposition of diamond films

Journal article

Absorption spectroscopy measurements are reported of the absolute number density (3.0±0.9×1012 cm-3) and vibrational temperature (3000±500 K) of C2(X1Σ g+) radicals in a DC arc activated chemical vapour deposition reactor under the standard operating conditions (3.3% CH4 in H2 and 6.4 kW discharge) used to grow polycrystalline diamond films. The ratio of number densities of C2 radicals in their ground (X1Σg+) and low-lying electronically excited (a3Πu) states is close to that expected from a Boltzmann distribution at the measured temperature, despite the more rapid rates of reaction of C2(X) with H2 and hydrocarbon molecules. © 2003 Elsevier B.V. All rights reserved.

Authors: Rennick, C; Smith, J; Ashfold, M; Orr-Ewing, A

• Journal: Chemical Physics Letters
• Volume: 383
• Issue: 5-6
• Pages: 518-522
• Publication date: 2004-01-15
• DOI: 10.1016/j.cplett.2003.11.089
• ISSN: 0009-2614
• Language: English