In order to confirm the possibility that hydrogen in Ta film migrates during SIMS measurement, the influence of primary ion beam irradiation conditions on the depth profile of hydrogen in a Ta film was investigated. Deuterium implanted in a Ta2O5/Ta/Ta2O5 structure was analyzed using Cs+ irradiation interruption. The result shows that hydrogen was discharged from the Ta film to the vacuum of the sample chamber during SIMS measurements with a Cs+ ion beam. The deuterium profile of the Ta film analyzed with an O-2(+) primary ion beam differed from those with Cs+ or Ar+ irradiations, and it depended on the incidence angle of the O-2(+) beam. According to these results, we propose a model where the hydrogen is discharged from Ta films to the vacuum of the sample chamber when Ta2O5 film is removed with Cs+ or Ar+ beam irradiation, but the hydrogen is not discharged when Ta2O5 film is formed on the Ta surface using O-2(+) primary beam irradiation. (C) 2008 Elsevier B.V. All rights reserved.