Sputtering yield reduction for nano-columnar W surfaces under D ion irradiation

• Published in: Nuclear materials and energy Vol. 37; p. 101507
• Main Authors: Brötzner, J., Cupak, C., Fellinger, M., Biber, H., Lopez-Cazalilla, A., Granberg, F., Kporha, F., Mutzke, A., González-Arrabal, R., Aumayr, F.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01-12-2023; Elsevier
• Subjects: BCA; Deuterium; Ray-tracing; Sputtering; Tungsten nano-columns; Deuterium; BCA; Ray-tracing; Tungsten nano-columns; Sputtering
• ISSN: 2352-1791; 2352-1791
• DOI: 10.1016/j.nme.2023.101507

This study investigates the sputtering properties of nano-columnar tungsten surfaces under 2 keV D2+ irradiation. It was conducted both by performing experiments in a highly sensitive quartz crystal microbalance setup as well as by numerical methods using two simulation codes called SPRAY and SDTrimSP-3D. A key question was whether the strong sputtering yield reduction observed in previous studies under 2 keV Ar+ irradiation is maintained when using a much lighter ion species like deuterium. For the latter, a substantially larger projected range in the material has to be expected. Therefore, a total confinement of the ion-solid interaction within the W nano-columns cannot be assumed a priori. However, both the experiments and the numerical simulations showed in good agreement that the geometrically induced sputtering yield reduction is still observed to the same extent despite the increased range of ions in the material. Thus, a potential application of such nano-columnar tungsten surfaces as plasma facing components in future nuclear fusion devices is not affected.
•Sputter yields of W nano-columns under D ion irradiation were measured and simulated.•The sputtering yield was shown to be reduced and its angular dependence flattened.•Reduction of the sputtering yield can be modelled using simple geometric arguments.