On the influence of metastable states and the behavior of the EEDF in the characterization of the negative glow of a N2-Ar discharge by OES

15th International Congress on Plasma Physics; 13th Latin American Workshop on Plasma Physics

Isola, L.^1 ; López, M.^1 ; Gómez, B.J.^1 ; Guerra, V.^2

Instituto de Fisica Rosario (CONICET-UNR), 27 Febrero 210 Bis., 2000 Rosario, Argentina^1

Instituto de Plasmas e Fusão Nuclear, Instituto Superior Tecnico, 1049-001 Lisboa, Portugal^2

关键词: Diagnostic techniques;    Discharge conditions;    Electron energy distribution functions;    Fabrication of thin films;    Mixture concentration;    Numerical derivation;    Optical emission spectroscopies (OES);    Second positive systems;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/511/1/012013/pdf
DOI  :  10.1088/1742-6596/511/1/012013

来源: IOP

【 摘 要 】

Optical emission spectroscopy (OES) is an essential diagnostic technique in many plasma systems, such as those used for surface treatments or fabrication of thin films. Despite the simplicity of application of OES, its interpretation is not straightforward. In particular, it requires the use of models, which due to the complexity and variety of discharge conditions, have not yet been fully understood [1]-[3]. In addition, Langmuir probes have been widely used to characterize plasmas. They allow the measurement of several parameters of interest, such as the electron density and temperature, as well as the determination of the electron energy distribution function (EEDF) by numerical derivation of the characteristic V-I [4] or by probe-current modulation [5]. In this work, some second positive system bands in the negative glow of an Ar-N2plasma at a pressure of 2.5 Torr were investigated both by OES and Langmuir probes, for different mixture concentrations. The main purpose of this study was to verify how metastable states and the behavior of the EEDF may influence the interpretation of OES data.