Determination of Electron Excitation Temperature in an RF-DC Hollow Cathode Nitrogen Plasma

Abstract

Abstract An RF-DC nitrogen glow discharge generated inside a rectangular hollow cathode was investigated as a source of nitrogen atoms. The plasma was produced at a frequency of 2 MHz at a low-pressure condition at the range of 30 to 100 Pa. The power generator was controlled at the RF voltage of 150 V and DC bias voltage of -500 V. The atomic nitrogen species have been detected by employing an optical emission spectroscopy technique. The use of a rectangular hollow cathode proves that the increase of nitrogen atoms species at a wavelength range of 700-900 nm was produced from the dissociation process of molecular nitrogen species. The present work aims to determine the electron excitation temperature based on the OES spectra. The excitation temperature was calculated by using the Boltzmann plot method. The result is the excitation temperature determined at the range of 0.59 to 0.71 eV. The excitation temperature in the hollow cathode was decreased with the increasing pressure.