Ar/O/sub 2/ gas pressure and arc current dependences of atomic components of zirconia prepared by intermittent zirconium arc PBII&D

Abstract

Summary form only given. Plasma-based ion implantation and deposition (PBII&D) is promising to modify the surface of substrate with a three dimensional shape, because both a conformal ion implantation and film deposition can be carried out. In the present research, zirconium oxide films were prepared using an intermittent zirconium arc discharge with arc currents of 30 A and 60 A in a mixed gas of argon/oxygen or pure oxygen gas, where the gas flow rate was varied from 100 sccm to 600 sccm, corresponding to the gas pressure of 0.12 Pa to 1.9 Pa. The arc current lasts 2-10 ms at every shot of the arc generation. The repetition rate is 0.25 Hz. The target with a diameter of 60 mm is placed at 150 mm apart from the arc source and is immersed in the plasma. The target applied voltage was varied from 0 to -10 kV. The atomic components of prepared films were investigated under variations of applied voltage and arc current. Stoichiometric films were obtained at Ar/O/sub 2/ flow rates of 300-400 sccm and 600 sccm for arc currents of 30 and 60 A, respectively, i.e., a large flow rate is necessary with increasing the arc current. In zirconia film preparation by PBII&D, the target voltage was varied under the conditions of an Ar/O/sub 2/ flow rate of 400 sccm and an arc current of 60 A. The Stoichiometric conditions were obtained at target voltages lower than -1 kV, while no stoichiometric films were not obtained at applied voltages higher than -2 kV. In case of no stoichiometric films, metallic zirconium components strongly appear. Thus, it is found that there is an optimal Ar/O/sub 2/ gas flow rate for respective ion fluxes. The arc in pure oxygen gas circumstance was unstable, and therefore, is inadequate to the zirconia film preparation.