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Laser absorption spectroscopy of aluminium atoms in pulsed magnetron discharge with pure argon, argon/oxygen, and argon/methane gas mixtures is reported. Time-averaged densities and temperatures of sputtered aluminium atoms were extracted from the absorption signal. The measured Al density depended almost linearly on the pulse current and showed a small dependence on pressure. Al atom temperature increased with discharge current and vice versa with pressure. A drastic decrease of the Al atom density was observed in the Ar/O2 mixture. The Al density dropped to a value close to zero once a critical oxygen gas flow rate was reached. This critical oxygen gas flow was significantly higher in pulsed mode than in DC mode.

Holographic interferometry of atmospheric RF barrier-torch discharge burning in argon and helium is reported. Holographic interferometer of Mach–Zehnder type with He–Ne laser was used for temperature measurement of neutral particles of working gas. Interference pattern was registered by a high-speed charge-coupled devices (CCD) camera. Resulting temperature ranged from 330 to 450 K. A slight difference between temperatures measured close to the glass nozzle outlet and close to the substrate was observed.

A High Power Impulse Magnetron Sputtering (HiPIMS) system was used for deposition of hematite thin films. Ion flux density on substrate was studied for different pulse discharge current densities corresponding to different pulsing frequencies of cathode voltage. Total thermal power flux density on substrate was investigated for the same plasma conditions as ion flux density was measured. Our findings revealed the pulse ion flux density on substrate linearly increases with pulse discharge current density whilst the total thermal power density decreases on about 50% when discharge pulsing frequency falls from 50 kHz to 100 Hz. Our previous investigation proved that the change in the discharge pulsing frequency has significant influence on microstructure of deposited hematite thin film. Results of our study imply that magnitude of the ion flux density on substrate leads to highly textured hematite thin film oriented along the desired (110) plane. Nevertheless the ion flux density on substrate is not substantial contribution to the total energy balance on substrate. Other elementary processes taking place on substrate probably can play a significant role in hematite thin film formation. The highest photocurrents of 0.86 mA cm−2 at 0.55 V and 0.99 mA cm−2 at 0.7 V vs. Ag/AgCl was revealed for the HiPIMS deposited films having the thickness of 25 nm and after the thermal treatment at 750 °C for 30 min. The photocurrents of 0.7 mA cm−2 at 0.55 V and 0.82 mA cm−2 at 0.7 V vs. Ag/AgCl of hematite films annealed at 650 °C for 30 min were reached when the voltage bias was applied to the FTO substrate during the deposition.