斜入射离子束辅助沉积对类金刚石薄膜结构影响的分子动力学模拟

Molecular dynamics simulation of the structure characteristic of diamond-like carbon films influence by oblique incidence ion-beam-assisted deposition

采用分子动力学(MD)模拟方法,从原子尺度上研究了离子束辅助沉积(IBAD)类金刚石(DLC)薄膜过程中离子束入射角对薄膜结构的影响.重点讨论了不同的离子束入射角所对应的薄膜表面模型,平均密度和sp3键含量.结果表明,离子束斜入射加强了入射原子的水平动能,从而加强了原子水平迁移;Ar离子斜入射时C原子迁移率均比垂直入射大,薄膜密度和sp3键含量都比垂直入射小.不同的离子束入射角随着到达比和入射能的变化,对薄膜结构的影响不同.离子束斜入射时可以得到不同结构的膜.

On atomic scale, using molecular dynamics （MD） simulation, the influence of different ion-beam incident angles on the structure of diamond-like carbon （DLC） films was discussed in the process of ion-beam-assisted deposition （IBAD）. The study focused on the model of film surface, average density and SP3 hybridization fraction under different ion beam incidence angles. The results showed that horizontal kinetic energy of the incident atoms was enhanced by the oblique incident assist ions, thereby the horizontal migration of the C-atoms were also enhanced. The ratio of migration of C-atoms with ion-beam oblique incidence became greater than with verticalineidace, however, the density of the film and SP3 hybridization fraction became smaller. The effect of different ion-beam incident angle on the films structure varies with the variation of assistance/deposition atomic ratio （Ar/ C） and incident energy. Thus films with different structures could be obtained when the incidence of ion-beam is oblique.