石墨烯薄膜的电迁移损伤演化模拟

石墨烯因其优异的电学性能,被期望成为下一代微电子器件领域中的重要材料。然而电迁移引起的孔洞或丘凸等损伤始终是威胁微电子器件可靠性的因素,因此研究石墨烯薄膜的电迁移损伤及失效变得尤为重要。我们在对石墨烯薄膜的应力迁移和热迁移问题研究的基础上开展了其电迁移损伤演化及失效的研究。本文将采用分子动力学方法,结合Tersoff势函数和速度形式的Verlet算法建立了单层石墨烯薄膜承载过程的理论模型,并对其有效性进行了验证,并模拟记录了石墨烯薄膜的电迁移损伤演化过程及失效特征。通过理论与数值模拟相结合的研究,进一步揭示了石墨烯薄膜电迁移损伤的演化规律与趋势,为微电子器件的设计和优化提供理论和技术参考。

Growth of Electromigration-Induced Damages in Graphene Material: A Simulation and Theoretical Study

We addressed the growth of electromigration-induced damages and failure mechanisms of graphene material. The damages, including voids and hillocks, were empirically approximated as the defects mainly formed in stretching, shearing and nano-indentation and possibly originated from stress migration and thermal migration, as we reported previously. The evolution of the damages was mathematically modeled with Tersoff potential and in Verlet algorithm, theoretically analyzed in molecular dynamics, numerically simulated with software LAMMPS and experimentally evaluated with results reported in literature. The evolution of the damages and possible failure mechanisms of both mono-layered and multi-layered graphene were simulated. The physics for electromigration, involving the temperature, atomic defects, layer number of graphene, impurity and size effect, remains to be investigated. We suggest that the simulated results be of some basic and technological interest in fabrication of micro-electronics and nano-electronics devices.