Development of plasma cleaning techniques for in-vessel optical components in ITER

作者：Arkhipov I^*; Gorodetsky A; Zalavutdinov R; Bukhovets V; Zakharov A; Mukhin E; Razdobarin A; Semenov V; Vukolov K; Mukhammedzyanov T; Gott Yu; Taranchenko A; Zvonkov S

来源：Journal of Nuclear Materials, 2011, 415(1): S1210-S1213.

DOI：10.1016/j.jnucmat.2010.09.038

Stream tube reactor coupled with H-2 dc glow discharge has been used for removal of a-C:H films deposited on prototypes of first mirror for Thomson Scattering diagnostics in divertor area of ITER. Deposition of a-C:H films was carried out in the same reactor using H-2/CH4 gas mixture. It was shown that removal rate of soft hydrocarbon films can reach 3 nm/min that will be quite enough for in situ cleaning of first mirrors placed in deposition-dominated areas of ITER. Moreover, cleaning ability of glow discharge was retained in spite of addition of small amounts (up to 6%) of methane to H-2 flow. The high-reflective metallic (Al) mirrors with protective oxide (ZrO2 or Al2O3) layer demonstrated high stability of reflective spectra during the deposition-erosion treatment. Besides, the removal rate of ITER-relevant a-C:H films deposited in magnetron discharge under X-ray radiation and tokamak T-10 during working pulses has been also estimated.

• 出版日期2011-8-1