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J. Laimer, G. Misslinger, H. Störi:
"Diamond deposition with chlorinated methanes: Investigation of the plasma chemistry";
Surface & Coatings Technology, 174-175 (2003), 938 - 942.

Methane and chlorinated methanes (CH₄, CH₃Cl, CH₂Cl₂, CHCl₃, CCl₄) were diluted in hydrogen and were decomposed in an electrodeless pulsed RF discharge sustained in a quartz glass tube. From the active plasma zone a small amount of the process gas was extracted by a helium flushed probe system, transported to and detected by a calibrated quadrupole mass spectrometer. The gas phase chemistry in the reactor was also modelled by CHEMKIN computer code. A reaction mechanism for the C-H-Cl system, which consists of 158 reactions and 40 species, was used to model the complex plasma chemistry. lt turned out that in the plasma the chlorinated methanes are decomposed very quickly to the main stable species HCl, CH₄ and C₂H₂. Chlorinated hydrocarbon radicals are only present within a few millisecond after the initial contact of the precursor with the plasma. At steady state, the radicals CH₃, Cl and H are most abundant. CH₄, C₂H₂ and also smaller amounts of C₂H₄ and C₂H₆ are in a quasi equilibrium. The chlorinated hydrocarbons were close to the detection limit.

Kevwords: Diamond; Plasma chemistry; Chlorinated methanes; Mass spectrometry; Kinetic modelling

http://aleph.ub.tuwien.ac.at/F?base=tuw01&func=find-c&ccl_term=AC04405852