Study on retention behavior and chemical states of energetic deuterium implanted into carbon-contained boron film

Retention behavior and chemical states of energetic deuterium (D) implanted into a carbon-contained boron film were investigated by XPS and TDS. It was found from the TDS results that D desorption processes were consisted of following four stages. Two of them were the desorptions of D bound to B as forming B-D-B and B-D bonds, and the others were thought to be that bound to C with different configurations. These results were consistent with the XPS results, showing the C-B (sp2), C-B (sp3) and C-C bonds were formed in the carbon contained boron film. These desorption peaks were attributed to B-C-D and C-C-D bonds, and most of D was mainly trapped by C and desorption temperature was higher than trapped by B, indicating that the D trapped by C would be critical issue for the hydrogen isotope retention control in fusion devices. It was concluded that D trapped by C, especially as C-C-D bond, was chemically stable even though at high temperature.