摘要
研究了在125℃,1×10^(3) A/cm^(2)条件下电迁移对Ni/Sn63Pb37/Cu BGA焊点界面反应的影响。回流后,在焊料/Ni界面处形成Ni_(3)Sn_(4)、在焊料/Cu界面处形成Cu^(6)Sn_(5)的金属间化合物。随着电迁移时间增加,芯片侧金属间化合物转变为(Cu,Ni)_(6)Sn_(5)类型化合物,印制板侧Cu6Sn5金属间化合物类型保持不变。电迁移过程中,阳极侧IMC厚度随电迁移时间增加而增加,界面反应为扩散控制,同一侧界面阳极侧IMC厚度大于阴极侧IMC厚度。阴极界面的生长规律较阳极侧复杂,初始阶段界面IMC的厚度较小,界面IMC随电迁移时间的增加而增厚;当界面的厚度达到一定值后,界面IMC的厚度随电迁移时间的增加而减小。
The effect of electromigration(EM)on the interfacial reaction in Ni/Sn63Pb37/Cu BGA solder joints is investigated under a current density of 1.0×10^(3) A/cm^(2) at 150℃.It has been found that the Ni3Sn4 intermetallic compounds form at the solder/Ni interface and the Cu6Sn5 IMCs form at the solder/Cu interface in the as-refl owed state.With increasing EM time,the IMCs form at chip interface transformed into(Cu,Ni)_(6)Sn_(5) type,while the IMCs at the PCB side don’t change.During EM,at the anode side the IMCs grow under the current density and follow the t^(1/2) law.At the same side,the IMCs at the anode side are thicker than those at the cathode side.The growth behavior of IMCs at the cathode side is complicated.Due to the initial IMCs in the as-refl owed are thin,the IMCs grow at the beginning of EM.After the IMCs at the cathode side increase to a critical thickness,they decrease thereafter.
作者
张飞
陈帅
王文龙
刘志丹
ZHANG Fei;CHEN Shuai;WANG Wenlong;LIU Zhidan(The 20th Research Institute of CETC,Xi’an 710071,China)
出处
《电子工艺技术》
2021年第4期207-209,239,共4页
Electronics Process Technology
基金
科工局基础科研项目。
