Plasma Cleaning of Metallic Mirrors from Carbon-Containing Films – New Possibilities for In Situ Monitoring of the Efficiency of Wall Conditioning in Fusion Devices
DOI:
https://doi.org/10.6000/2369-3355.2018.05.03.2Keywords:
Fusion devices, plasma, wall cleaning, electrical resistance, carbon film thickness.Abstract
The method proposed for measuring the erosion rate of the carbon film, pre-deposited on the mirror-like surface of the test metallic samples, directly during wall conditioning procedures in a fusion device. The practical realization of the method provided at the DSM-2 stand where deuterium plasma produced in conditions of electron resonance at frequency 2.45 GHz used for cleaning the samples. For controlling C-film thickness the time variation of electrical conductivity of the circuit ‘film+plasma+entire scheme’ was measured. The final cleaning stage sets according to the saturation section corresponding to the resistance of the entire measuring scheme. To check the state of full purification of samples from a carbon-containing film the reflectance at normal incidence in the wavelength 220-650 nm was measured before C-film deposition, just after C-film deposition, and after finishing the cleaning procedure. In all cases (16 experiments) the approach of total resistance to the ‘entire resistance’ of the scheme in use was supported by restoration of the reflectance of stainless steel samples to its initial value.
The method can be reversed, i.e. allows one to control in situ the appearance of a contaminating layer growing on the surface of a metal sample, preliminary cleaned before being installed in a vacuum vessel
References
Voitsenya VS, Konovalov VG, Ryzhkov IV et al., First results with collecting probes in U-2M torsatron. Problems of Atomic Science and Technology. 2018, №6. Series: Plasma Physics (118), p. 17-20. http://vant.kipt.kharkov.ua/ARTICLE/VANT_2018_6/article_2018_6_17.pdf
Orlinski DV, Voitsenya VS, and Vukolov KYu. First mirrors for diagnostic systems of an experimental fusion reactor I. Simulation mirror tests under neutron and ion bombardment. Plasma Devices Oper 2007; 15: 33-75. http://www.tandfonline.com/loi/gpdo20 DOI: https://doi.org/10.1080/10519990601160075
Tymoshenko AI, Taran VS, Tereshin VI. Plasma characteristics of two-step vacuum-arc discharge and its application for a coatings deposition. Probl. Atom. Sci. Techn., series: Plasma Phys 2007; 1: 179-81. http://vant.kipt.kharkov.ua/ARTICLE/VANT_2007_1/article_ 2007_1_179.pdf
Voitsenya VS, Bardamid AF, Donné AJH. Experimental simulation of the behaviour of diagnostic first mirrors fabricated of different metals for ITER conditions. Open Physics J 2016; 3: 23-54. https://pure.tue.nl/ws/portalfiles/portal/37530269 DOI: https://doi.org/10.2174/1874843001603010023
Babaev VG, Guseva MV, Savchenko NF, Novikov ND, Khvostov VV, Flad P. High oriented sp1-carbon film. Journal of Surface Investigation: X-ray, synchrotron and neutron studies 2004; issue 3: 16-27 (in Russian).
Dasgupta D, Demichelis F, Tagliaferro A. Electrical conductivity of amorphous carbon and amorphous hydrogenated carbon. Phil Mag 1991; 63: 1255-66.
http://dx.doi.org/10.1080/13642819108205558 DOI: https://doi.org/10.1080/13642819108205558
Konshina EA. Amorphous hydrogenated carbon and its use in optical devices. Monograph. St. Petersburg, 2010 (in Russian). Available at https://books.ifmo.ru/book/599/amorfnyy_gidrogenizirovannyy_uglerod_i_ego_primenenie_v_opticheskih_ustroystvah.htm
Sinel’nikov BM, Tarala VA, Prokhoda TN. Synthesis and study of the properties of diamond-like carbon films obtained from methane in RF plasma. Bulletin of the Southern Scientific Center of the Russian Academy of Sciences 2009; 5 (issue 2): 120-4 (in Russian). http://www.ssc-ras.ru/files/files/120-124_sin.pdf
Fantz U, Wünderlich D. Franck–Condon factors, transition probabilities and radiative lifetimes for hydrogen molecules and their isotopomeres. INDC(NDS)-457 (Reproduced by the IAEA in Vienna, Austria May 2004). https://inis.iaea.org/collection/NCLCollectionStore/ _Public/37/088/37088524.pdf
Weinert M, Wimmer E, Freeman AJ. Chemical sputtering of carbon materials due to combined bombardment by ions and atomic hydrogen. Phys Rev 1986; B26: 4571-8. https://journals.aps.org/ prb/pdf/10.1103/PhysRevB.26.4571
Jacob W, Hopf C, Schlüter M. Chemical sputtering of carbon materials due to combined bombardment by ions and atomic hydrogen. Phys Scr 2006; T124: 32–6. http://iopscience.iop.org/ article/10.1088/0031-8949/2006/T124/007/pdf DOI: https://doi.org/10.1088/0031-8949/2006/T124/007
Arumainayagam Christopher, Lee Hsiao-Lu, Nelson Rachel B, Haines David R, Gunawardane Richard P. Low-energy electron-induced reactions in condensed matter. Surf Sci Rep 2010; 65: 1-44. https://doi.org/10.1016/j.surfrep.2009.09.001 DOI: https://doi.org/10.1016/j.surfrep.2009.09.001
Wang Chao, Diao Dongfeng, Fan Xue, Chen Cheng. Graphene sheets embedded carbon film prepared by electron irradiation in electron cyclotron resonance plasma. Appl Phys Lets 2012; 100: 231909. https://doi.org/10.1063/1.4727894 DOI: https://doi.org/10.1063/1.4727894
Shepperd Kristin R. Low-energy electron induced processes in hydrocarbon films adsorbed on silicon surfaces. Ph D. Thesis. https://smartech.gatech.edu/bitstream/handle/1853/29648/shepperd_kristin_r_200908_phd.pdf
Fischer R, Dose V. Electron energy distribution reconstraction in low-pressure helium plasmas from optical measurements. Plasma Phys Control Fusion 1999; 41: 1109-23. http://citeseerx.ist.psu.edu/ viewdoc/download?doi=10.1.1.10.6295&rep=rep1&type=pdf DOI: https://doi.org/10.1088/0741-3335/41/9/304
Aleiferis S, Svarnas P. Automated electrostatic probe device of high resolution and accuracy. Rev Sci Instr 2014; 85: 123504. https://doi.org/10.1063/1.4903354 DOI: https://doi.org/10.1063/1.4903354
Aleiferis Spyridon. Experimental study of H- negative ion production by electron cyclotron resonance plasmas. Ph. D. Thesis, Université Grenoble Alpes, 2016.
https://tel.archives-ouvertes.fr/tel-01492954/document
Kurutz U, Friedl R, Fantz U. Investigations on Cs-free alternatives for negative ion formation in a low pressure hydrogen discharge at ion source relevant parameters. Plasma Phys Contr Fusion 2017; 59: 075008. https://doi.org/10.1088/1361-6587/aa7120 DOI: https://doi.org/10.1088/1361-6587/aa7120
Yang Peng, Yang Wantai. Surface chemoselective phototransformation of C−H bonds on organic polymeric materials and related high-tech applications. Chem Rev 2013; 113: 5547-94. https://doi.org/10.1021/cr300246p DOI: https://doi.org/10.1021/cr300246p
Chen Mao, Zhong Mingjiang, Johnson Jeremiah A. Light-controlled radical polymerization: mechanisms, methods, and applications. Chem Rev 2016; 116: 10167−211, Special Issue: Photochemistry in Organic Synthesis. https://doi.org/10.1021/acs.chemrev.5b00671 DOI: https://doi.org/10.1021/acs.chemrev.5b00671
Skurat Vladimir E, DorofeevYurij I. The transformations of organic polymers during the illumination by 147.0 and 123.6 nm light. Die Angewandte Makromolekulare Chemie 1994; 216: 205-24 (3877). https://doi.org/10.1002/apmc.1994.052160114 DOI: https://doi.org/10.1002/apmc.1994.052160114
Fozza AC, Roth J, Klemberg-Sapieha JE, Kruse A, Holländer A, Wertheimer MR. Oxidation and ablation of polymers by vacuum-UV radiation from low pressure plasmas. Nucl Instrum Methods Phys Res Sect B Beam Interact Mater At 1997; 131: 205-10. https://doi.org/10.1016/S0168-583X(97)00154-7 DOI: https://doi.org/10.1016/S0168-583X(97)00154-7
Sakamoto Y, Ishii S, Yano V, et al. Electron cyclotron resonance discharge cleaning of JFT-2 tokamak (JAERI). J Nucl Mater 1980; 93&94: 333-7. https://doi.org/10.1016/0022-3115(80)90344-X DOI: https://doi.org/10.1016/0022-3115(80)90344-X
Janev RK, Langer WD, Evans K Jr, Post DE Jr. Elementary Processes in Hydrogen-Helium Plasmas. Cross Sections and Reaction Rate Coefficients. Springer-Verlag Berlin Heidelberg New York London Paris Tokyo. 1987. 326 p. http://b-ok.cc/book/ 2124621/df22e7
Downloads
Published
How to Cite
Issue
Section
License
Policy for Journals/Articles with Open Access
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.
- Authors are permitted and encouraged to post links to their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work
Policy for Journals / Manuscript with Paid Access
Authors who publish with this journal agree to the following terms:
- Publisher retain copyright .
- Authors are permitted and encouraged to post links to their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work .