高密度芯片激光钎焊温度场及应力场数值模拟研究  

Numerical Simulation of Temperature-stress Field in Laser Soldering of Bumps

作　　者：宰建轩 李辉 葛晓宏 李奋强 王启凡 黄安国[2] ZAI Jianxuan;LI Hui;GE Xiaohong;LI Fenqiang;WANG Qifan;HUANG Anguo(Fujian Key Laboratory of Functional Materials and Applications,School of Materials Science and Engineering,Xiamen University of Technology,Xiamen 361024,China;School of Materials Science and Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)

机构地区：[1]厦门理工学院材料科学与工程学院,福建省功能材料及应用重点实验室,福建厦门361024 [2]华中科技大学材料科学与工程学院,湖北武汉430074

出　　处：《电焊机》2024年第3期80-88,共9页Electric Welding Machine

基　　金：福建省科技计划项目-对外合作项目(2020I0027);福建省自然科学基金面上项目(2021J011212)。

摘　　要：旨在探讨激光钎焊工艺参数对高密度芯片制造中凸点焊点质量的影响。通过有限元方法建立了三维瞬态热耦合数值模型,并利用高斯体热源模型和iSoldering软件模拟了SnAgCu钎料凸点激光钎焊的温度场和应力场,研究不同功率10 W、15 W、20 W和不同光斑半径0.09 mm、0.3 mm、0.5 mm下SnAgCu钎料钎焊焊点的变化规律。研究发现,激光功率和光斑半径是影响焊点质量的关键参数。在部分参数不变的情况下,随着激光功率的增大,钎料熔化更完全,润湿性更好,但也会产生更大的等效应力。增大光斑半径会导致焊点温度和等效应力降低。经过数值模拟和实际钎焊焊点的对比,结果表明:当激光功率为15 W、光斑半径为0.09 mm、焊接速度为0.1 mm/s时,SnAgCu凸点激光钎焊的焊点质量最佳,模拟凸点钎焊的焊点与实际钎焊结果吻合度达到85%,验证了模拟结果的准确性和可靠性。同时探讨了钎料与焊盘之间生成的金属间化合物厚度对焊点质量的影响,为提高焊点连接强度提供了理论依据。The study aims to explore the impact of laser brazing process parameters on the quality of bump solder joints in high-density chip manufacturing.A three-dimensional transient thermal coupling numerical model was established using finite element methods,and the Gaussian volume heat source model and iSoldering software were utilized to simulate the temperature and stress fields of SnAgCu brazed convex points.The research investigated the variation rules of SnAgCu brazing solder joints under different powers of 10 W,15 W,20 W,and different spot radii of 0.09 mm,0.3 mm,and 0.5 mm.The findings revealed that laser power and spot radius are the key parameters affecting solder joint quality.With some parameters remaining unchanged,an increase in laser power resulted in more complete brazing material melting,better wettability,but also greater equivalent stress.The increase in spot radius led to a decrease in solder joint temperature and equivalent stress.By comparing numerical simulations with actual brazed joints,the results showed that the best quality of SnAgCu convex point laser brazing solder joints was achieved when the laser power was 15 W,the spot radius was 0.09 mm,and the welding speed was 0.1 mm/s.The simulated convex point brazing solder joints matched the actual brazed results with an accuracy of 85%,verifying the accuracy and reliability of the simulation results.This study provides theoretical guidance for improving actual laser brazing processes and explores the impact of the thickness of intermetallic compounds formed between the brazing material and the solder pad on solder joint quality,offering a theoretical basis for enhancing solder joint connection strength.

关 键 词：激光钎焊 凸点 有限元分析 温度场 应力场 

分 类 号：TG454[金属学及工艺—焊接]