弹性磨抛轮加工硅片面形预测模型及试验验证  

Surface Shape Prediction Model of Silicon Wafers Ground by the Elastic Grind-polishing Wheel and Test Verification

作　　者：高尚[1] 任佳伟 康仁科[1] 张瑜[1] 李天润 GAO Shang;REN Jiawei;KANG Renke;ZHANG Yu;LI Tianrun(State Key Laboratory of High-performance Precision Manufacturing,Dalian University of Technology,Liaoning Dalian 116024,China)

机构地区：[1]大连理工大学高性能精密制造全国重点实验室,辽宁大连116024

出　　处：《表面技术》2024年第3期22-27,46,共7页Surface Technology

基　　金：国家重点研发计划(2022YFB3605902);国家自然科学基金(51975091,51991372);河南省重大科技专项(221100230100)。

摘　　要：目的为分析弹性磨抛轮磨削硅片面形精度变化的影响因素,优化加工参数以获得良好的磨削面形。方法通过建立考虑弹性磨抛轮转速、硅片转速、偏心距等参数的弹性磨抛轮磨粒运动轨迹模型,结合单颗磨粒切削深度,提出了弹性磨抛轮加工硅片的材料去除非均匀性预测方法,建立了基于弹性磨抛轮磨削硅片的面形预测模型,并通过不同转速比下的磨削试验验证了预测模型的准确性。结果面形预测模型仿真出的面形与弹性磨抛轮加工试验后的硅片面形一致,均呈“凸”形,且PV值随转速比的增大而增大。转速比为1时,磨削后硅片面形PV值为0.54μm,仿真模型计算出的PV值为0.49μm,转速比为5时,磨削后硅片面形PV值为2.12μm,仿真模型计算出的PV值为2.38μm。结论磨削试验面形PV值与模型计算面形PV值的预测误差小于13%,建立的面形预测模型能够成功预测硅片的面形规律,可以分析加工参数对硅片面形的影响规律。由面形预测模型分析可知,转速比对硅片面形精度有影响,且随着转速比的增加,硅片面形不断恶化,因此在实际加工中,应选择较小的转速比进行加工,以获得更优的硅片面形精度。Silicon wafer is the most widely used substrate material for integrated circuits.Ultra-precision grinding is widely used in the back thinning and flattening of silicon wafer and it can achieve high dimensional accuracy,fast material removal and relatively small wear.The elastic Grind-polishing wheel is a new type of non-woven structure grinding tool with low elastic modulus and ultra-fine abrasive grains,which can obtain high surface and subsurface quality grinding wafers.It is prepared by ultra-fine ZrO2 abrasive particles and low elastic modulus wool fibers.The surface roughness of the silicon wafer after grinding can reach 0.45 nm,and the subsurface damage depth is about 67 nm.It has significant advantages in processing efficiency,process integration and environmental friendliness,and has great development potential.However,as one of the important evaluation indexes of the surface,the surface shape rule of the workpiece is rarely studied.The material removal of the silicon wafer during the grinding process is uneven and the surface profile of the workpiece is poor.The work aims to analyze the affecting factors of the surface of the workpiece in the grinding by the elastic Grind-polishing wheel and optimize the processing parameters to obtain good surface shape.In previous studies,the surface shape rule was only speculated based on the distribution density of the abrasive trajectory on the surface of the silicon wafer,and the actual material removal amount could not be calculated to obtain an accurate surface shape.In this study,by establishing the elastic Grind-polishing wheel abrasive trajectory model based on the elastic Grind-polishing wheel speed,silicon wafer speed,eccentricity and other processing parameters,combined with the establishment of considering the calculation of Grit-cutting depth and calculating the material removal depth of different radial positions of the silicon wafer,the prediction method of material removal non-uniformity in silicon wafer grinding was proposed.The surface shape predicti

关 键 词：磨抛轮 硅片 面形仿真 磨粒切削深度 去除均匀性 磨削 

分 类 号：TG580.6[金属学及工艺—金属切削加工及机床]