CMP过程中抛光盘作用外力的影响因素分析

Factors influencing the applied force on a single micro-particle from pad in CMP

根据芯片/磨粒/抛光盘三体接触当量梁的弯曲假设,建立了更加准确合理的抛光盘作用在磨粒上的外力的理论模型,并通过实例对前人的模型和新模型进行对比。最后借用已有分子动力学模拟结果对理论模型进行验证。结果表明作用在单个磨粒上的外力与磨粒的直径、磨粒的浓度、抛光盘的弹性模量有关,理论计算值与分子动力学模拟结果基本一致。

In accordance with hypothesis of the equivalent beam bending for a three body contact among wafer/particles/pad,a more precise and reasonable mathematical model about the applied force on particles from pad is developed.The model comprehensively considers the influence of most valuables in chemical mechanical polishing process including pad elastic modulus,particle diameter and slurry concentration.Then,through theoretical calculation of an example,the new model and former models are compared and analyzed.Finally,after the validation of the molecular dynamics simulation of sliding contact between a single micro-particle and a smooth flat surface,it is found that the theoretical value predicted by the model agrees well with the result of the molecular dynamics simulation under same chemical mechanical polishing conditions.