Bremen 2017 – wissenschaftliches Programm
P 23.11: Poster
Mittwoch, 15. März 2017, 16:30–18:30, HS Foyer
Electronegativity and oxygen kinetics during E-H transition in inductively coupled radio frequency plasmas . — •Thomas Wegner1 and Jürgen Meichsner2 — 1Max-Planck-Institute for Plasma Physics, Greifswald, Germany — 2Institute of Physics, University of Greifswald, Greifswald Germany
The electronegativity and oxygen kinetics in inductively coupled plasma at 13.56 MHz was evaluated during the E-H transition by comprehensive plasma diagnostics to determine experimentally the particle density for electrons, negative atomic oxygen ions, metastable and ground state molecular oxygen as well as the effective electron temperature and gas temperature. Furthermore, the negative atomic oxygen ion density was calculated by their balance equation taking into account the experimentally determined densities and temperatures as well as the rate coefficients from literature. The calculated negative ion density is compared with the measured negative ion density by laser photodetachment experiment and by the electron density peak in the early afterglow due to collisional detachment. The three different methods provide adequate agreement in the negative ion density and describe the continuous decrease of the electronegativity over two orders of magnitude from the E-mode to the H-mode. Additionally, the dominant elementary processes are identified for negative ion formation and recombination in the E-mode and H-mode, respectively.
Funded by the DFG Collaborative Research Center Transregio 24, project B5.