Correlation of boron and nitrogen contents with the flux of energetic Ar+ ions at the substrate during the deposition of BN coatings by RF magnetron sputtering

Abstract Thin films of BN x O y have been deposited by RF magnetron sputtering from a BN target in Ar plasma (1 Pa) at different substrate RF bias conditions. The possibility of obtaining high-quality BN coatings at a target–substrate distance greater than the mean free path of B and N atoms has been investigated. The discharge characteristics have been measured by means of an electrostatic probe of the Langmuir type. The flux and energy of the Ar + ions have been determined and correlated to the net contents of boron and nitrogen as measured by means of the N(d,p) and 11 B(p,α) nuclear reactions. The results deduced by XRD, FTIR and nanohardness measurements show that under the experimental conditions used, the flux of Ar + ions at the substrates is insufficient to promote the formation of crystalline BN films.