Feasibility of determining electron energy distribution function using optical emission lines in low-pressure Ar/Kr discharge

Abstract

The electron energy distribution function (EEDF) were reconstructed from both collected emission line intensities and a collisional radiative model. The obtained EEDFs from this method were compared with those obtained from Langmuir probe diagnostics over a wide range of discharge conditions ( ∼1010–1012 cm − 3, ∼ 1–3 eV, ≲ 67 Pa) for low-pressure Ar/Kr discharges. In particular, we investigated the factors that affect the accuracy and uncertainty of the EEDF via sensitivity analysis. The following conclusions were obtained: (1) using a sufficiently large number (≳20–30) of Ar/Kr2p-1s emission lines can increase the accuracy of the determined EEDF; (2) for discharges with low electron densities, using emission line sets for both Ar and Kr [instead of only one (Ar or Kr) line set] can significantly reduce the uncertainty in the determined EEDF.