Thermal desorption behavior of deuterium implanted into polycrystalline diamond

In the present study, the thermal desorption behavior of deuterium implanted into diamond was investigated by means of TDS and XPS. From the results of TDS experiments, the most of all implanted deuterium was desorbed by forming D2 mainly, and two desorption peaks were observed in the temperature range from 700 to 1100 K and from 1100 to 1300 K. The lower temperature deuterium desorption from the diamond was similar to that from HOPG. However, the D/C value of the diamond was approximately 0.2, which was almost half the value of the HOPG. The C 1s XPS spectra of diamond were shifted towards lower energy with increasing heating temperature above 773 K. In addition, the π–π∗ transition peak appeared above this temperature. These meant that the disordered diamond structure were reconstructed through the desorption of deuterium, and stabilized by formation of a graphite network.