Fluence dependence and thermal stability of defects in helium-implanted cubic zirconia


Fluence dependence and thermal stability of defects in helium-implanted cubic zirconia

Saude, S.; Grynszpan, R. I.; Anwand, W.; Brauer, G.; Grob, J. J.; Le Gall, Y.

Slow positron implantation spectroscopy investigations of yttria-stabilized cubic zirconia implanted with 50 keV He ions detect, at 60% of the projected range, a concentration of defects maximum, which may constitute a barrier for the diffusion of helium towards the surface. The Doppler broadening lineshape dependence on the fluence suggests a change in the nature of defects above 4 x 10**16 ions/cm**2, with an enhancement of the trapping efficiency. These defects evolve into large bubbles by Ostwald ripening after annealing at temperatures higher than 573 K, as suggested by their distribution narrowing. Above 973 K, a breaking-up of the bubbles occurs, with He release and diffusion towards the surface and eventual out-gassing.

Keywords: ion implantation; zirconia; radiation effects; positrons

Permalink: https://www.hzdr.de/publications/Publ-6016
Publ.-Id: 6016