The Evolution Behavior of Defects in the Nanofilms of W/Cu and W Probed by Doppler Broadening Positron Annihilation Spectroscopy

Abstract:

W/Cu multilayer nanofilms and pure W nanofilms were prepared in pure Ar and He/Ar mixing atmosphere by radio frequency magnetron sputtering method. The defect evolution of the samples was characterized by Doppler broadening positron annihilation spectroscopy (DB-PAS).The results show that plenty of defects can be produced by introducing helium (He) into W/Cu multilayer nanofilms. With the natural storage time increasing, the helium located in the near surface of W/Cu multilayer nanofilm would be released gradually and induce the coalescence of the helium related defects due to the diffusion of the helium and defects. In addition, the pure W nanofilms were irradiated by 30 keV helium ions and 40 keV hydrogen (H) ions in sequence at room temperature. From the DB-PAS analysis, it can be shown that a large number of vacancy-type defects are produced due to the He and/or H irradiation. H ions would be trapped by He related defects and produced He-H-V complexes.

• Periodical: Defect and Diffusion Forum (Volume 373)
• Pages: 104-107
• DOI: https://doi.org/10.4028/www.scientific.net/DDF.373.104
• Online since: March 2017
• Authors: Ling Wang, Ai Hong Deng*, Kang Wang, Yong Wang, Xiao Bo Lu, Yuan Wang, Ran Li
• Keywords: DB-PAS, Helium Bubbles, Interface, Multilayer Nanofilms

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