Detection of deuterium trapping sites in tungsten by thermal desorption spectroscopy and positron annihilation spectroscopy

Abstract

Thermal desorption spectroscopy (TDS) of tungsten implanted with D2+ ions was performed after irradiation with 8 MeV-electrons, 5.0keV-D2+, and 6.0 MeV-Fe3+. The release peak temperatures of the TDS spectra are discussed. Positron annihilation lifetime (PAL) measurements of electron-irradiated tungsten were also performed, showing that single vacancies migrate a sufficient distance to arrive at a sink or meet interstitial-type defects during annealing at 673K. A decrease in the PAL was detected for single vacancies that contain deuterium atoms. The peak temperature of deuterium release from dislocations was lower than that from single vacancies. In samples irradiated with 6.0 MeV-Fe3+, the effect of Fe contamination on deuterium trapping and the deuterium release from voids were detected. These tendencies correspond to previous works.

Keywords

• Tungsten
• Hydrogen isotopes
• Thermal desorption spectroscopy
• Positron annihilation
• Defects
• Ion implantation