减薄晶圆损伤层残余应力和力学性能测量方法研究

项目名称： 减薄晶圆损伤层残余应力和力学性能测量方法研究

项目编号： No.11502005

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 数理科学和化学

项目作者： 陈沛

作者单位： 北京工业大学

项目金额： 20万元

中文摘要： 集成电路 (IC) 芯片在提高集成度的同时，也在朝着轻薄化方向发展。芯片基底材料硅的减薄是成功产业化轻薄IC芯片、3D IC芯片的核心技术之一。晶圆在减薄过程中所造成的表面损伤会导致晶圆力学性能下降，并引入残余应力导致晶圆翘曲，最终影响晶圆的加工性能。然而减薄晶圆残余应力和力学性能的测量技术还不完善，不能对晶圆质量进行完整评估。本项目拟改进薄膜鼓泡法测试，将其应用于测量减薄晶圆残余应力和力学性能（包括断裂强度和杨氏模量）。为解释减薄损伤对残余应力和力学性能的影响机理，本项目将运用扫描电镜 (SEM)、透射电镜 (TEM)和拉曼光谱法观测损伤层微观结构，研究损伤层微观结构形成规律。然后通过分析减薄工艺参数对损伤层形成过程的影响，研究减薄工艺参数对残余应力和力学性能的作用规律。最后进行减薄工艺参数优化，实现对损伤层的有效控制，达到降低减薄晶圆残余应力并提高力学性能的目标。

中文关键词： 晶圆减薄工艺；鼓泡法测试；残余应力；损伤层；工艺参数优化

英文摘要： The development of Integral Circuits (IC) has a tread of improving integrated level, reducing weight and thickness. The thinning of wafer, which is the base of IC, is the key technology to successfully industrialize ultra-thin IC chips and 3D IC chips. During wafer grinding, surface damage will lower the mechanical properties，and form wafer bowing by inducing residual stress. However, the technology to determine the residual stress and mechanical properties of ground wafer is not well developed, and the quality of the ground wafer cannot be well evaluated. This study will apply a modified bulge test to determine residual stress and mechanical properties (including fracture strength and Young’s modulus) of ground wafer. To explain the mechanism of grinding damage on residual stress and mechanical properties, this study will employ Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and raman spectroscopy to observe the microstructure of damaged layer, and study the formation rule of damaged layer. Then by analyzing the effect of machining parameters on the formation of damaged layer, the effect of machining parameters on residual stress and mechanical properties will be studied. Finally, the machining parameters will be optimized, and the formation of damaged layer will be controlled, therefore, the ultimate goal of reducing residual stress and improving mechanical properties will be achieved.

英文关键词： Wafer thinning technology;Bulge test;Residual stress;Damaged layer;Machining parameter optimization