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Title: Positron annihilation spectroscopy investigation of vacancy defects in neutron-irradiated 3 C -SiC

We described positron annihilation spectroscopy characterization results for neutron-irradiated 3 C -SiC, with a specific focus on explaining the size and character of vacancy clusters as a complement to the current understanding of the neutron irradiation response of 3 C -SiC. Positron annihilation lifetime spectroscopy was used to capture the irradiation temperature and dose dependence of vacancy defects in 3 C -SiC following neutron irradiation from 0.01 to 31 dpa in the temperature range from 380C °to 790C .° The neutral and negatively charged vacancy clusters were identified and quantified. The results suggest that the vacancy defects that were measured by positron annihilation spectroscopy technique contribute very little to the transient swelling of SiC. Additionally, we used coincidence Doppler broadening measurement to investigate the chemical identity surrounding the positron trapping sites.Finally, we found that silicon vacancy-related defects dominate in the studied materials and the production of the antisite defect C Si may result in an increase in the probability of positron annihilation with silicon core electrons.
 [1] ;  [1] ;  [1] ;  [1] ;  [2]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
  2. (United States)
Publication Date:
Grant/Contract Number:
AC05-00OR22725; SC0006661
Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 95; Journal Issue: 10; Journal ID: ISSN 2469-9950
American Physical Society (APS)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). High Flux Isotope Reactor (HFIR)
Sponsoring Org:
USDOE Office of Science (SC), Fusion Energy Sciences (FES) (SC-24)
Country of Publication:
United States
OSTI Identifier:
Alternate Identifier(s):
OSTI ID: 1346582