Helium irradiation effects on retention behavior of deuterium implanted into boron coating film by PCVD

Abstract Helium irradiation effects on the retention of energetic deuterium implanted into the boron coating film were investigated by means of X-ray photoelectron spectroscopy (XPS) and thermal desorption spectroscopy (TDS). It was found, by XPS, that the B 1s peak was shifted to lower binding energy side by He+ ion irradiation and the FWHM was extended. These facts show that the some defects were introduced into the boron coating film by He+ ion irradiation. From TDS experiment, the deuterium retention, especially the amount of B–D terminal bond, increased by the pre-He+ ion irradiation. However, it decreased by the post-He+ ion irradiation. These experimental results indicate that the B–D terminal bond was mainly influenced by the He+ ion irradiation because the two neighbor B–D bonds have to dissociate simultaneously for the B–D–B bridge bond.