Characteristics of an atmospheric-pressure radio frequency-driven Ar/H2 plasma discharge with copper wire in tube

This paper investigates a plasma discharge driven by a 13.56 MHz radio frequency (RF) power supply at atmospheric pressure, in which a copper wire is inserted in the discharge tube for the deposition of Cu films. The results show that the jet plasma formation originates from the discharge between the copper wire and induction coil because of its electrostatic field. The axial distribution of the plasma parameters in the RF plasma jet, namely the gas temperature, excitation temperature, and electron number density, is determined by diatomic molecule OH fitting, Boltzmann slope, and H𝛽 Stark broadening, respectively. The discharge current significantly declines when a small amount of hydrogen is added to the argon as the plasma-forming gas, and the gas temperature of discharge plasma increases considerably