摘要
铜线表面钯层特征是影响芯片封装过程中烧球和键合质量的重要因素。采用无卤直接涂镀工艺,制备了不同涂镀速度和涂镀温度下的镀钯铜线,研究了涂镀速度对镀层形貌和无空气焊球(free air ball,FAB)特征的影响。结果表明:随着涂镀速度增加,涂镀时间减少,钯颗粒在铜线表面分布的均匀性变差,局部分布不均匀的钯颗粒团聚引起钯颗粒浓度较高,镀层表面钯颗粒团聚区域增加。在涂镀速度50 m/min下,镀层表面钯分布较为均匀。随着涂镀速度的增加,FAB球直径逐渐减小;镀钯铜线表面Pd颗粒团聚区域和未团聚区域的钯含量差增大,FAB球尺寸的一致性逐渐下降。在较低涂镀速度50 m/min下,FAB球表面钯分布比较均匀;在较高的涂镀速度100 m/min下,镀层表面大量团聚的钯颗粒重熔后在FAB球表面呈大面积连续的富钯区,钯再分布的均匀性较差。从FAB球尺寸的一致性和表面钯再分布的均匀性方面考虑,涂镀速度50 m/min和涂镀温度400℃为镀钯铜线涂镀较佳的工艺参数。
The characteristics of palladium layer on the surface of copper wire are important factors affecting the quality of free air ball(FAB)and bonding during chip packaging.In this paper,palladium-coated copper wires with different coating speeds and coating temperatures are prepared by halogen-free direct coating process.The effects of coating speed on the morphology of the coating and the characteristics of FAB are studied.The results show that with the increase of coating speed,the coating time decreases,and the uniformity of the distribution of palladium particles on the surface of the copper wire becomes worse.The agglomeration of palladium particles with uneven local distribution causes the concentration of palladium particles to be too high,and the agglomeration area of palladium particles on the surface of the coating increases.Under the plating speed of 50 m/min,the distribution of palladium on the surface of the coating is more uniform.With the increase of coating speed,the diameter of FAB decreases gradually.The difference of palladium content between the agglomeration area and the non-agglomeration area of Pd particles on the surface of Pd-coated copper wire increases,and the consistency of FAB sphere size gradually decreases.At a lower coating speed of 50 m/min,the distribution of palladium content on the surface of FAB is relatively uniform.At a higher coating speed of 100 m/min,a large number of agglomerated palladium particles on the surface of the coating are remelted to form a large area of continuous palladium-rich area on the surface of the FAB,and the uniformity of palladium redistribution is poor.Considering the uniformity of FAB size and surface palladium redistribution,the coating speed of 50 m/min and the coating temperature of 400℃are the better process parameters for the coating of palladium-coated copper wire.
作者
李纪渊
李韶林
宋克兴
周延军
曹军
曹飞
苏辉
LI Jiyuan;LI Shaolin;SONG Kexing;ZHOU Yanjun;CAO Jun;CAO Fei;SU Hui(Henan Key Laboratory of Non-ferrous Materials Science and Processing Technology,Henan University of Science and Technology,Luoyang 471023,Henan,China;Henan Academy of Sciences,Zhengzhou 450052,China;School of Mechanical and Power Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China;School of Materials Science and Engineering,Xi’an University of Technology,Xi’an 710000,China)
出处
《材料工程》
北大核心
2026年第3期213-221,共9页
Journal of Materials Engineering
基金
国家自然科学基金(U21A2051)
河南省科技研发计划联合基金(222102230064,222103810037)
河南省科学院研发项目(220910009)。
关键词
铜键合丝
镀钯铜线
涂镀速度
无空气焊球
copper bond wire
palladium-coated copper wire
coating speed
free air ball
