Abstract. As a potential solution to next-generation nanolithography, directed self-assembly (DSA) of block copolymers (BCPs) is still restrained in high-volume manufacturing primarily due to its defectivity issue. Though defects possess greater free energies than aligned morphologies and are highly energetically unfavorable, they can be kinetically trapped by the energy barriers and persist for a long time during annealing. Therefore, understanding the kinetics of defect annihilation is crucial in revealing the mechanism of defect formation and in further reducing defectivity in DSA. We focus on two types of predominant defects in DSA—dislocation and bridge. A kinetic model of each defect type is developed through statistical analysis of experimental data, providing insight into possible approaches of further defect reduction. We also investigate the impact of annealing temperature and film thickness on annihilation kinetics and discuss the reasons behind the observed results. By simply optimizing annealing conditions and film thickness, we have successfully reduced the total defect density by 1 order of magnitude. Though these findings are based on polystyrene-b-poly(methyl methacrylate) (PS-b-PMMA), we anticipate they could be readily applied to other BCP platforms as well.

中文翻译：

---

减少定向自组装缺陷的动力学方法

摘要。作为下一代纳米光刻的潜在解决方案，嵌段共聚物 (BCP) 的定向自组装 (DSA) 在大批量生产中仍然受到限制，主要是由于其缺陷问题。尽管缺陷比排列的形态具有更大的自由能并且在能量上非常不利，但它们可以在动力学上被能量势垒捕获并在退火过程中持续很长时间。因此，了解缺陷消除的动力学对于揭示缺陷形成机制和进一步降低 DSA 中的缺陷率至关重要。我们专注于 DSA 中的两种主要缺陷——位错和桥接。通过对实验数据的统计分析，开发了每种缺陷类型的动力学模型，从而深入了解进一步减少缺陷的可能方法。我们还研究了退火温度和薄膜厚度对湮灭动力学的影响，并讨论了观察结果背后的原因。通过简单地优化退火条件和薄膜厚度，我们成功地将总缺陷密度降低了 1 个数量级。尽管这些发现基于聚苯乙烯-b-聚（甲基丙烯酸甲酯）（PS-b-PMMA），但我们预计它们也可以很容易地应用于其他 BCP 平台。