Development of Simplified Simulation Method of Diffusion Based on Monte Carlo Analysis

大规模集成电路中导体等微元器件的失效主要是由原子级缺陷引起的。缺陷核化通常通过沿沿着边界扩散而发生。然而，分子动力学模拟不能应用于真实的部件中的过程，因为它可以在很短的时间内模拟原子的行为。针对原子沿表面沿着跳跃的情况，提出了一种模拟长周期缺陷形核过程的蒙特卡罗方法。本文从原子力学的角度分析了铝导体晶界开槽的形核过程。该方法成功地模拟了切槽的形成。然后，在熔化温度附近的晶界和表面之间的交叉点附近的原子的运动是由分子动力学模拟和凹槽的形成可以识别为低SIGMA边界。分子动力学结果验证了新方法的有效性。

The failure of microelement such as conductors in a LSI is caused mostly by the atomic scale defects. The defect mucleation often takes place by diffusion along boundaries. The molecular dynamics simulation, however, can not be applied to the process in a real component because it can simulate the behavior of atoms in a very short period. A Monte Carlo method to simulate the process of defect nucleation in a longer period is proposed focusing on the jumps of atoms along the surface. In this study, the nucleation process of grain boundary grooving in an aluminum conductor is analyzed in terms of atomic mechanics. The formation of grooving is successfully simulated by the method. Then, the motion of atoms near an intersection between grain boundary and surface near the melting temperature is simulated by a molecular dynamics and the formation of grooving can be recognized for low SIGMA boundaries. The validity of new method is examined by the molecular dynamics result.