Neutral gas temperature in silicon based DC MHCD operated in various gases near atmospheric pressure

Sylvain Iséni (1) , Ronan Michaud (1) , Philippe Lefaucheux (1) , Goran Sretenovic (2) , Volker Schulz-von Der Gathen (3) , Remi Dussart (1)

1 GREMI - Groupe de recherches sur l'énergétique des milieux ionisés
2 University of Belgrade [Belgrade]
3 RUB - Ruhr University Bochum = Ruhr-Universität Bochum

Micro hollow gas discharges (MHCD) have been on high interest to produce highly ionized gas geometries have been developed to produce micro-cavities, MEMS fabrication technologies offer several advantages. For instance, a silicon (Si) based MHCD allows for reducing significantly the electrode gap (8 µm SiO2 layer) and the cavity size (typically from 50 µm to 200 µm diameter, 30 µm depth) [2,3]. Operated in DC at pressure ranges from 2.104 Pa to 105 Pa, the plasma ignites in the cavity in the so-called normal regime. Transition to the abnormal regime leads to an expansion of the plasma out of the cavity. While Si-based DC MHCD were used to suffer from their short lifetime, recent advances on the MHCD design allow for extending their lifetime over several days of operation [4]. This study focuses on the accurate measurement of the gas temperature in and out the cavity, operated in different regimes, by means of space resolved optical emission spectroscopy. Two approaches are applied depending on the gas mixture (He, Ar, N2): either by studying the profile of resonant atomic lines taking in to account the Van der Waals broadening or with the determination of the N2(C-B) rotational temperature. Limitations of the latter approach will be discussed specifically. Heat transfer and temperature gradient will be discussed with regard to the geometry and the material properties of the present MHCD design. 1. K. H. Schoenbach and K. Becker, Eur. Phys. J. D 70, 29 (2016). 2. L. Schwaederlé, M. K. Kulsreshath, L. J. Overzet, P. Lefaucheux, T. Tillocher, and R. Dussart, J. Phys. Appl. Phys. 45, 065201 (2012). 3. C. H. Sillerud, P. D. D. Schwindt, M. Moorman, B. T. Yee, J. Anderson, N. B. Pfeifer, E. L. Hedberg, and R. P. Manginell, Phys. Plasmas 24, 033502 (2017). 4. R. Michaud, V. Felix, A. Stolz, O. Aubry, P. Lefaucheux, S. Dzikowski, V. Schulz-von der Gathen, L. J. Overzet, and R. Dussart, Plasma Sources Sci. Technol. 27, 025005 (2018).

Domaines: Plasmas; Micro et nanotechnologies/Microélectronique; Optique / photonique; Thermique [physics.class-ph]

Sylvain Iséni, Ronan Michaud, Philippe Lefaucheux, Goran Sretenovic, Volker Schulz-von Der Gathen, et al.. Neutral gas temperature in silicon based DC MHCD operated in various gases near atmospheric pressure. International Workshop on Microplasmas - IWM 10, May 2019, Kyoto, Japan. ⟨hal-02189151⟩