Summary:
An electron cyclotron resonance (ECR) plasma reactor developed at the European Spallation Source Bilbao has been operated in pulsed mode at 50 Hz to study the breakdown-process dynamics by time-resolved diagnostics. Injected power, reflected power, electrical-biased probe saturation current, and light emission were measured simultaneously for three different magnetic fields: under ECR, ECR, and asymmetric over ECR profiles. Gas pressure, power, and duty cycle have been used in a parametric study obtaining information about microwave (MW) coupling and plasma formation stages during the breakdown process. The study is relevant for designers that need to extract short beam pulses from a 2.45 ECR ion source for any application because the total breakdown time measured is defined as corresponding to reach the steady-state plasma parameters. A simple model of residual electron density evolution between pulses is proposed to describe the MW coupling as a function of incoming power and duty cycles.
Keywords: Electron cyclotron resonance (ECR) plasma source, plasma breakdown, pulsed ECR ion source.
JCR Impact Factor and WoS quartile: 0,868 - Q4 (2012); 1,300 - Q3 (2023)
DOI reference:
https://doi.org/10.1109/TPS.2012.2222933
Published on paper: December 2012.
Published on-line: October 2012.
Citation:
O.D. Cortázar, A. Megia-Macías, A. Vizcaíno-de-Julián, Experimental study of breakdown time in a pulsed 2.45-GHz ECR hydrogen plasma reactor. IEEE Transactions on Plasma Science. Vol. 44, nº. 12, pp. 3409 - 3419, December 2012. [Online: October 2012]
