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This paper describes effects of vacuum ultraviolet (VUV) optical emission from the plasma on the secondary electron emission coefficient (SEEC) in PIII processes. To examine this, time-resolved measurements of the VUV emission intensity and the SEEC are performed in continuous and square-wave-modulated discharges. For all the measured data, a good linearity between the SEEC and the VUV intensity is found out, and the ion-induced SEEC can be distinguished from the photon-induced SEEC. In the afterglow of the modulated discharge, the SEEC decreases because the VUV emission intensity. Therefore, ion implantation in the afterglow allows us to reduce a current requirement of the pulse generator, leading to low-cost PIII processes. [Copyright &y& Elsevier]

Abstract: This paper reports on plasma parameters and ion composition of droplet-free Zr ion source for plasma immersion ion implantation and deposition (PIII&D). Zirconium (Zr) ions were obtained by ionizing sputtered Zr atoms in inductively-coupled argon discharge. The characteristics of plasma density, plasma potential and electron temperature were typical ones of such a inductive discharge, and the plasma parameters were not significantly influenced by mixing the sputtered Zr atoms into the plasma. Actually, the main ionic component was still Ar+ ions, and the ion density ratio of [Zr+]/[Ar+] was as low as ∼8%. Increase in sputtering rate of the Zr source will be necessary to improve the ion density ratio. [Copyright &y& Elsevier]

Abstract: Zirconium oxide films were prepared by plasma-based ion implantation and deposition (PBII&D), where a zirconium pulse arc discharge was generated in O2/Ar gas mixture. The plasma was maintained for approximately 3ms, and the ion current at the substrate was detected in a time range from 1 to 10ms after the arc initiation. At O2/Ar pressures of 2.6–3.0Pa, a stoichiometric film was obtained, while at a pressure lower than 2.2Pa, the film also contained ZrO x (x <2) phase as well as ZrO2 phase. In the absence of argon gas, the plasma became unstable, which resulted in shortage of zirconium ions in the plasma, and hence, a stoichiometric condition was not found. [Copyright &y& Elsevier]