以KrF准分子激光器为激光源,对目前工业上常用的硅片研磨抛光液的主要成分Al₂O₃颗粒进行激光清洗的试验和理论分析。建立一维热传导模型,利用有限元分析软件MSC.MarC模拟硅片表面的温度随激光作用时间和能量密度的分布。通过理论计算,量化了颗粒所受到的清洗力以及其与硅片表面之间的粘附力,理论预测出1μm Al₂O₃颗粒的激光清洗阈值为60 mJ/cm²。在理论分析的指导下,利用 248 nm、30 ns 的KrF准分子激光进行单因素试验,研究激光能量密度、脉冲个数、激光束入射角度对激光干法清洗效率的影响,并且实验验证了清洗模型以及场增强效应对激光清洗结果的影响。

The laser cleaning of Al₂O₃ particles which are the main component of the silicon wafer lap-polishing solution commonly used in industry nowadays was studied by experiments combined with theoretical analysis.The simple heat-conduction model was built and the temperature field on silicon wafer surface during laser cleaning was simulated using the finite element method.The adhesion force between the particle and the substrate and cleaning force acting on the particles were calculated,and the theoretical threshold of laser cleaning 1 μm Al₂O₃ is 60mJ·cm².Under the guidance of the mechanism analysis,a serial of laser dry cleaning experiments were carried out to study the dependence of laser cleaning efficiency on laser fluence,numbers of pulse,and laser beam incidence angle on silicon wafer surface using 248 nm,30 ns,KrF excimer laser,Which confirmed the clean model as well as the effect of the field enhancement on laser cleaning.