Molecular dynamic simulation of interaction of C+ ions and fusion material tungsten

作者：Tian Shuping; He Pingni; Zhang Jingquan; Pan Yudong; Gou Fujun^*

来源：Chinese Journal of Vacuum Science and Technology, 2013, 33(4): 351-357.

DOI：10.3969/j.issn.1672-7126.2013.04.11

• Carbon deposition
• Carbon membrane
• Deposited rate
• Energy increase
• Fusion material
• Possible mechanisms
• Simulated results
• Sputtering rate

The interaction of the impinging C+ion beam and the fusion material W was modeled and simulated, based on molecular dynamics, to understand the possible mechanisms responsible for the carbon deposition and carbon ion sputtering of W surface in fusion. The impacts of the interaction conditions, including the incident C+energy and exposure, on the interaction were simulated. The simulated results show that the carbon atom exists mainly in sp3state on W surfaces, and that the energy of incident C+strongly affects the deposition and sputtering rates. For example, as the energy increases, the deposition rate of C varies in a decrease-increase mode;whereas the sputtering rate changes in an increase-decrease mode. At an energy of 50 eV and an exposure of 3.11×1016cm-2, a thin carbon membrane forms on W surface, at an energy of 150 eV and 250 eV, carbon atoms are implanted in top layers of W, no carbon membrane can be observed. As the energy increases, the peaks of the depth profiles of C-W and C-C bonds move deeper inside W, with an increasingly thicker layer of C-W bond and a thickness unchanged layer of C-C bond. The sputtering of W, rarely occurs though, may seriously damage the lattice.

• 出版日期2013
• 单位四川大学