OPTICAL-EMISSION SPECTROSCOPY OF ACTIVE SPECIES IN A TICN PVD ARE DISCHARGE

In this article, it is shown that a good correlation is obtained betwe en optical emission spectroscopy (OES) measurements of the plasma ligh t and the electron spectroscopy for chemical analysis (ESCA) of the Ti CN coating of a steel wafer in a physical vapor deposition (PVD) are d ischarge reactor. The reactor works in a N-2-CH4 mixture, at a total p ressure of about 10(-2) mbar, and the plasma is created from a cathodi c titanium are with an evaporation voltage of 20 V and current intensi ty of 60 A. The TiCN deposition takes place at 20 cm from the are disc harge. The study performs the measurement of the relative intensities, spatially resolved, of the N-2(+) line at 427.5 nm, the Ti lines at 4 30.1 nm and 430.5 nm and the CH line at 431.4 nm as a function of the respective concentrations of the methane-nitrogen mixture. The ratio o f the intensities of the plasma lines CH and N-2(+) is quasi-linearly related to the ratio of the concentrations C and N measured by ESCA on the coating. On the basis of the results obtained we are developing O ES as non-intrusive and in situ diagnostic of the plasma reactive spec ies for controlling the TiCN deposition process in an industrial react or.