含硅通孔结构晶圆减薄中的表面/界面微结构演化研究

For the processing of wafer thinning with through silicon vias(TSV) in the microelectronic technology of 20nm/14nm, controlling defect and maintaining microstructure stability of surface and interface of wafer is very crucial. Only understanding the microstructure evolvement of surface and interface, controlling defect and maintaining microstructure stability in wafer thinning is achieved, and optimizing the processing of wafer thinning with TSV. In this proposal of the project, the microstructure evolvement mechanism of surface and interface of different materials( Si,SiO2, Copper) under multi-physical loads will be key point investigated in the processing of wafer thinning with TSV. The trans-scale microstructure evolution model of surface and interface coupling multi-physical fields will be built for wafer thinning, and the deformation of surface and interface of different materials in wafer thinning with TSV will be analyzed with the Bottom-up method from atom to continuum, the deformation mode of surface and interface will be understood. By the processing experiments for wafer thinning with TSV and microstructure analysis, the evolvement mechanism of surface and interface will be completely realized, and the mode of origin, importing, and expanding of defect in surface and interface will be acquainted; and so, the figuration and spreading mechanism of surface and interface demage of different materials in wafer thinning can be built. The optimization method of processing preferences can be acquired, wafer thinning with TSV of high performance, controlling defect, stability, and low stress will be implement in this proposal of the project.

对于20nm/14nm技术以下的含硅通孔(TSV)结构晶圆减薄工艺来说，实现缺陷可控、结构稳定的高效晶圆减薄是关键。认识减薄过程中表面/界面微结构的演变机制,才能优化减薄工艺，实现减薄过程表面/界面微结构稳定与缺陷可控。本项目围绕含硅通孔结构晶圆减薄过程中多物理场作用下的异质材料（硅、二氧化硅、铜等）表面/界面微结构演变，建立耦合多物理场的晶圆表面/界面微结构的跨尺度演变模型；自下而上（Bottom-Up）跨尺度分析晶圆减薄过程中异质材料表面/界面结构演变；通过晶圆减薄工艺实验与微观检测，分析减薄过程中异质材料界面/表面微结构演变机理，建立晶圆减薄过程中表面/界面缺陷的产生、引入、扩展模式，揭示晶圆减薄过程中表面/界面损伤的工艺参数诱导规律；提出含硅通孔晶圆减薄工艺的优化方法，实现缺陷可控、结构稳定、高效率、低应力的晶圆减薄。

面向含硅通孔(TSV)结构晶圆减薄工艺，项目建立了TSV结构的减薄模型，构建了跨尺度分析方法，为实现缺陷可控、结构稳定的高效晶圆减薄提供了理论依据。项目以分子动力学为核心，研究了微纳尺度下的损伤层与宏观工艺参数的关联，揭示了减薄过程微结构演变过程和耦合机制，总结了多种表面/界面结构在减薄过程中的特性，设计了以时空平均和相空间平均的跨尺度分析方法。利用跨尺度方法和TSV减薄模型提供的工艺边界，通过试验实现了损伤控制和工艺优化，并成功将12寸TSV晶圆减薄至40μm以下。