工件旋转法磨削硅片的亚表面损伤深度预测  

Prediction for subsurface damage depth of silicon wafers in workpiece rotational grinding

作　　者：高尚[1] 李天润 郎鸿业 杨鑫 康仁科[1] GAO Shang;LI Tianrun;LANG Hongye;YANG Xin;KANG Renke(Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学精密与特种加工教育部重点实验室,辽宁大连116024

出　　处：《光学精密工程》2022年第17期2077-2087,共11页Optics and Precision Engineering

基　　金：国家自然科学基金重大项目(No.51991372);国家自然科学基金面上项目(No.51975091);国家自然科学基金重点项目(No.51735004);国家重点研发计划项目(No.2018YFB1201804-1)。

摘　　要：工件旋转法磨削是大尺寸硅片正面平整化加工和背面减薄加工的主要方法,但磨削加工不可避免地会在硅片表面/亚表面产生损伤。为了预测工件旋转法磨削硅片产生的亚表面损伤深度,优化硅片磨削工艺,根据工件旋转法磨削过程中硅片磨削表面的几何轮廓参数、硅片磨削表面的材料去除机理和压痕断裂力学理论建立了磨粒切削深度、表面粗糙度Ra和亚表面损伤深度之间的数学关系,推导出工件旋转法磨削硅片的亚表面损伤深度预测模型,并通过硅片超精密磨削试验对模型进行了验证与分析。结果表明,工件旋转法磨削硅片的亚表面损伤深度随表面粗糙度Ra的增大而增大,通过预测模型计算的磨削硅片亚表面损伤深度预测值与硅片亚表面损伤深度实测值的误差小于10%,建立的亚表面损伤深度预测模型能够为超精密磨削硅片的亚表面损伤控制和硅片高效低损伤磨削工艺的优化提供理论指导。Workpiece rotational grinding is the primary machining process for the bare wafer flattening and pattern wafer back-thinning of large silicon wafers.However,the grinding process inevitably causes surface and subsurface damage on the ground silicon wafers.The subsurface damage depth of ground silicon wafers is critical for evaluating the grinding process.To predict the subsurface damage depth of silicon wafers in workpiece rotational grinding and optimize the grinding parameters,the wafer surface topography,material removal mechanism,and the underlying fracture mechanics were comprehensively analyzed,and a mathematical relationship among the grain cut depth,surface roughness Ra,and subsurface damage depth was derived.Subsequently,a predictive model for the subsurface damage depth of silicon wafers due to workpiece rotational grinding was established,and silicon wafer grinding experiments were conducted to validate the model.The experimental results indicate that the subsurface damage depth of silicon wafers machined via workpiece rotational grinding increases with the ground surface roughness.The predicted subsurface damage depths of ground silicon wafers are consistent with the actual measured values,and the accuracy of predictive model is less than 10%.These results can provide a basis for the subsurface damage control and parameter optimization of grinding of large-sized silicon wafers.

关 键 词：磨削 单晶硅片 表面粗糙度 亚表面损伤深度 

分 类 号：TN305[电子电信—物理电子学] O786[理学—晶体学]