Diagnostics of magnetically enhanced RF discharges in methane, argon and methane - argon mixtures

The determination of plasma parameters in RF capacitive discharges enhanced by an external magnetic field using emission spectroscopy, double Langmuir probes and thermocouple methods is reported. The gas temperature, rotational temperature of CH radicals, electron temperature, and charged particle and atomic hydrogen densities as functions of the discharge parameters are determined. The system operating parameters can be adjusted in the following ranges: gas pressure in the discharge chamber 0.1 - 10 Pa; discharge power 80 - 200 W; magnetic field strength 0 - 200 G. Pure methane and pure argon, as well as mixtures of methane and argon in various proportions were used as working gases. In addition, carbon films were deposited on glass substrates and their optical properties were investigated. It is shown that the external magnetic field has a significant influence on both plasma parameters and properties of the deposited films.