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

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 ( ne similar to 1010-1012 cm - 3, Teff similar to 1-3 eV, pgas less than or similar to 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 (greater than or similar to 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.

Automated summary

This paper investigates the reconstruction of the electron energy distribution function (EEDF) using collected emission line intensities and a collisional radiative model. The obtained EEDFs are compared with those obtained from Langmuir probe diagnostics, and the factors affecting the accuracy and uncertainty of the EEDF are analyzed via sensitivity analysis. The study finds that using a sufficient number of emission lines and considering multiple elements can improve the accuracy and reduce the uncertainty of the determined EEDF for low-density discharges.