Magnetron sputtering modes during pulsed deposition process determined by the analysis of power supply parameter

The goal of this paper is to present a new control method of reactive magnetron sputtering. The processes of reactive magnetron sputtering of aluminum target in Ar + O₂ atmosphere in high efficiency deposition and low efficiency deposition mode were studied. The mode of magnetron operation — metallic, transient, reactive (compound) — was determined by the analysis of medium frequency (MF) magnetron voltage and current waveforms and a circulating power (power supply parameter). This parameter enables monitoring of any mismatch between plasma-magnetron impedance and the resonant circuit of power supply. The experiments show that the Al_xO_y layer formation conditions could be determined by use of the power supply parameters. Conclusions were supported by the refractive index and dielectric constant measurements.