Plasma and Fusion Research

Volume 17, 1302094 (2022)

Letters

Fuzz Growth Process under He-W Co-Deposition Conditions
Wanqi SHEN, Shin KAJITA1), Hirohiko TANAKA, Quan SHI2) and Noriyasu OHNO
Graduate School of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603, Japan
1)
Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561, Japan
2)
National Institute for Fusion Science, 322-6 Oroshi-cho, Toki 509-5292, Japan
(Received 13 June 2022 / Accepted 5 July 2022 / Published 15 August 2022)

Abstract

Helium (He)-Tungsten (W) co-deposition experiments were conducted in the linear plasma device Co-NAGDIS at a temperature of 1223 K to observe the characteristics of fuzz growth on the W surface with auxiliary W deposition. The dependence on the deposition rate of W was investigated and a clear difference in fuzz thickness was found between He-only and co-deposition experiments. In addition, the fuzz structures on a single sample exhibited a spatially nonuniform distribution, which was probably caused by the nonuniformity in the deposition rate.

Keywords

fuzz, helium, co-deposition, tungsten

DOI: 10.1585/pfr.17.1302094

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