Determination of the excited argon states densities in high-frequency capacitive discharge

Abstract

An experimental measurement of the density of excited argon states 1s5, 1s4, 1s3, and 1s2 was carried out for an rf capacitive discharge in argon at a frequency of 13.56 MHz and 81 MHz for two pressures of 50 and 100 mTorr in a wide range of discharge applied power. A collision-radiative model was developed to calculate the densities of 1s states from the known electron density and the electron energy distribution function. The electron energy distribution function is obtained from a self-consistent discharge simulation based on the Particle in cell with Monte Carlo collisions model. It is shown that the calculated densities of the metastable states of argon are in good agreement with the experimentally measured ones. The calculated resonance state densities are underestimated.