第21卷第8期 2013年8月
1004-924X(2013)08-2064-07
文章编号
光学精密工程
Optics and Precision Engineering
Vol.21No.8
Aug.2013
铜互连兆声清洗中结构损伤预测的有限元分析
黄雅婷1*，孟春玲'，董秀萍'，路新春
（1.北京工商大学材料与机械工程学院，北京100048； 2.清华大学摩擦学国家重点实验室，北京100084）
摘要：尽管用于铜及低介电材料(low-材料)互联加工的兆声清洗工艺可以提高纳米颗粒的去除率，但清洗过程中的声波能量会破坏微小器件结构从而导致器件功能失效。本文采用有限元分析法分析和预测了兆声波的破坏作用，研究了铜及low-k材料互联结构在兆声清洗过程中的应力分布及变形。基于ABAQUS软件，采用二维有限元模型对循环布线
最大应力集中在铜及low-k材料键合处将导致low-k材料分层。当线宽为22nm时，应力和结构变形达最大值，分别为 1379MPa和3.074nm;之后随线宽增加最大应力应变值均减小。另外，兆声频率增大不改变应力应变分布规律，对应
力应变极值影响亦不明显。分析及预测结果与工业实践得到的结果相符。关键词：化学机械抛光；兆声清洗；铜互联；有限元分析
中图分类号：TN305
文献标识码：A
doi;10.3788/OPE. 20132108, 2064
Finite element analysis of structure failure in Cu
interconnectmegasoniccleaning
HUANG Ya-ting'', MENG Chun-ling', DONG Xiu-ping', LU Xin-chun
(l.School of Material and Mechanical Engineering,
BeijingTechnology andBusinessUniversity,Beijing100048,China;
2.StateKeyLaboratoryofTribology,TsinghuaUniversity,Beijing100084,China)
+Correspondingauthor,E-mail:huangyat@gmail.com
Abstract: Although megasonic cleaning can remove effectively nano particles in the Cu/low-k intercon nection post-Chemical Mechanic Polishing (post-CMP) cleaning, the megasonic energy in cleaning may also cause extensive damage to microstructures. To predict the damage, the structural deforma-tion and the stress distribution of Cu and low-k materials in megasonic cleaning were examined with Finite Element Analysis(FEA). Two-dimensional models were used in analysis of the stress-strain of a typical cell impacted by a caviation bubble in the circulate wiring pattern and all of the simulations were performed with ABAQUS. The results show that the maximum stress is concentrated in the binding area between Cu and low-k, which will result in the delamination of low-k materials. When the line width is 22 nm, the stress and deformation reach the largest values by 1 379 MPa and 3. 074
收稿日期：2013-03-02；修订日期：2013-04-15，
基金项目：国家自然科学基金青年基金资助项目（No,51205006)；清华大学擦学国家重点实验室开放基金资助项
目（No,SKLTKF11A01)；北京市委组织部优秀人才计划资助项目（No，2011D005003000006）；北京市教委重点资助项目（No.KZ201210011012)