聚变堆中H刻蚀碳氢薄膜的分子动力学模拟  

Molecular Dynamics Simulation of H-Etching of Hydrocarbon Films in Fusion Reactor

作　　者：吕晓丹[1] 秦尤敏[1,2] 赵成利[1] 宁建平[1,2] 贺平逆[1] 苟富均[3,4] 

机构地区：[1]贵州大学等离子体与材料表面作用研究所,贵阳550025 [2]贵州大学材料与冶金学院,贵阳550003 [3]辐射物理及技术教育部重点实验室,成都610064 [4]荷兰皇家科学院等离子体所

出　　处：《真空科学与技术学报》2011年第3期320-325,共6页Chinese Journal of Vacuum Science and Technology

基　　金：国际热核聚变实验堆(ITER)计划专项(批准号:2009GB104006);贵州省优秀青年科技人才培养计划(批准号:700968101)资助的课题

摘　　要：使用分子动力学方法模拟了低能H原子与碳氢薄膜的作用过程,以了解基于核聚变装置中等离子体与C基材料的相互作用机制。模拟中使用REBO(reactive empirical bond order)势函数来描述C-H体系中原子间的相互作用,并使用Berendsen热浴来控制体系的温度。文中着重探讨了入射能量对低能H原子刻蚀碳氢薄膜的影响,入射能量分别为0.3,1,5和10eV。模拟结果显示随着入射能量的增加,H原子的吸附率增加,C原子和H原子的刻蚀率增加。同一能量下H原子比C原子更易发生刻蚀。通过讨论发现在H原子与碳氢薄膜作用过程中,当能量大于1 eV时,由于入射的H原子先沉积在表面并与表面原子发生反应形成碳氢化合物,然后在后续入射粒子的轰击下碳氢化合物在表面发生解吸附现象,从而导致了C原子的刻蚀,因此C原子的刻蚀发生主要是化学增强的物理溅射。The etching of hydrocarbon films by low energy hydrogen radicals in the nuclear fusion reactor was simulated,based on molecular dynamics,to understand the interaction of the plasma and the carbon-based materials.In the simulation,the reactive empirical bond order（REBO） potential was used to describe the interaction in the C-H system,and Berendsen thermostat scheme was employed in temperature control.The influence of the impinging H atoms with energies of 0.3,1,5 and 10 eV,respectively,on the etching rate of the hydrocarbon films was evaluated.The simulated results show that the incident energy strongly affects the etching rates of H and C.For instance,as the incident energy increases,the adsorption rate of H,as well as the etching rates of H and C increase.Moreover,at a given incident energy,H atoms outperform C atoms in etching.The hydrocarbon,formed by the impinging H atoms with energy greater than 1 eV and surface C atoms,can be easily desorbed by H bombardment,resulting in etching of carbon.And the chemical enhanced physical sputtering accounts for the etching of carbon

关 键 词：分子动力学 碳氢薄膜 吸附 刻蚀 

分 类 号：O484[理学—固体物理]