Research Information System
CONTRIBUTIONS TO PLASMA PHYSICS, vol.1, no.1, pp.1-10, 2025 (SCI-Expanded)
The thermionic vacuum arc (TVA) is a plasma source that generates highly ionized metal vapor plasmas via anodic evaporation, with independent control over plasma parameters through operational adjustments. This study investigates copper (Cu) plasmas produced by a TVA system under stable-state conditions, focusing on the dependencies of electron temperature (Te) and electron number density (Ne) on operating parameters such as arc current (Iarc) and cathode filament current (If). Optical emission spectroscopy (OES) in the 200–1000 nm range was employed to analyze spectral line intensities of neutral Cu atoms. Te was determined via the Boltzmann plot method, yielding values between 4720 ± 250 K and 5370 ± 300 K as the Iarc increased from 300 to 1200 mA (at a fixed If of 18.5 A), while increasing the If from 16 to 19 A elevated Te from 4580 ± 250 K to 5180 ± 300 K, demonstrating distinct contributions of both parameters to electron heating. Ne was determined using Stark broadening analysis, revealing a weak dependence on operating parameters, with values ranging from (5.0 ± 0.8) × 1016 cm−3 to (8.9 ± 0.9) × 1016 cm−3). These findings highlight the TVA's unique capability to controllably tailor plasma properties, making it a promising candidate for advanced coating processes requiring precise plasma parameter modulation.