Thermal annealing effects on chemical states of deuterium implanted into boron coating film

To reveal interaction between boron coating film and energetic hydrogen isotopes, chemical states of deuterium implanted into the boron coating films deposited on graphite by using DC glow discharge in a diborane diluted helium have been studied. The XPS measurements showed the possibility of the formation of B–D and C–D bonds by D2+ ion implantation. The TDS experiments indicated that deuterium desorption took place in two stages, which were attributed to the desorption processes from the trapping sites of B–D and C–D bonds. The results of the XPS measurements after D2+ ion implantation revealed that the peak areas of the B–D and C–D bonds began to decrease at 310 and 473 K and the peaks almost disappeared at 873 and 1073 K, respectively. These results suggest that the trapping site of the B–D bond is largely influenced by thermal annealing effects compared with that of the C–D bond.