多级粗糙表面对抛光液微流动影响的数值分析

Numerical Simulation of Multilevel Rough Surface Effects on the Microscale Flow of Polishing Slurry

由于特征线宽的进一步细微化,超大规模集成电路的进一步发展受到平坦化技术发展水平的制约。抛光液流动性能是影响平坦化加工性能和效率的重要因素之一,为增强抛光液的流动性,在抛光垫表面增加沟槽是有效的技术手段。以带沟槽抛光垫多级粗糙表面的抛光液微流动为研究对象,采用多级粗糙表面计算机模拟生成技术和计算流体动力学新方法格子Boltzmann方法,对抛光液在多级粗糙间隙内的流动过程进行分析。初步研究抛光垫多级粗糙表面的抛光液微流动特性,并且分析抛光垫表面形貌特征对抛光液流动的影响。结果表明,所提出的抛光液微流动研究方法可以用来分析抛光垫几何参数对抛光液输送过程的影响,并且具有很好的统计特性,这为抛光垫的修整和新一代抛光垫的设计制造提供了一种理论研究方法。

Further development of ultra-large-scale integration（ULSI） is restricted by the state-of-the-art of the planarization technology due to the further micronization of the characteristic line width.Flow property of the polishing slurry is one of the important factors influencing the efficiency and performance of the planarization process.It is verified in practice that the grooved pad will enhance the transport of the slurry to and from the wafer center.The microscale flow of polishing slurry on the multilevel rough surface of grooved pad is taken as a study object.The simulated production technique is used to generate the multilevel rough surface,and a new computational fluid dynamic method,Lattice Boltzmann method（LBM）,is used to analyze the flow of slurry in the multilevel rough gap.The flow characteristic of the slurry on the multilevel rough surface and the effect of pad topography on the flow of slurry are studied preliminarily.The results show that the present method can be used to analyze the effect of the geometrical parameters of pad on the transport of the polishing slurry and possesses good statistical property.The theoretical research method developed is helpful to the design and manufacture of a new generation pad and also to the pad conditioning.