论文部分内容阅读
应用X射线衍射技术原位测量分析了Cu/Sn3.0Ag0.5Cu/Cu焊点在电流密度为4×103A/cm2的作用下阴极和阳极界面的应力演变。结果表明:焊点阴极和阳极界面的应力演变非常复杂,大致分为4个阶段。第一个阶段,由于金属热膨胀效应促使焊点界面的压应力开始升高;第二个阶段,应力松弛的影响使得压应力开始降低;第三个阶段,电迁移的作用使得阳极界面压应力增加而阴极界面由压应力向拉应力转变;第四个阶段,阳极处晶须和小丘的形成释放了压应力,阴极处的拉应力继续增加。试样抛光后发现,在焊点阳极界面形成了一层厚度均匀的Cu6Sn5金属间化合物。
The stress evolution of Cu / Sn3.0Ag0.5Cu / Cu solder joint at the cathode and anode interface under the current density of 4 × 10 3 A / cm 2 was analyzed by X-ray diffraction. The results show that the stress evolution at the solder joint cathode and anode interface is very complicated and can be roughly divided into four stages. In the first stage, the compressive stress at the interface of solder joints starts to increase due to the thermal expansion effect of the metal. In the second stage, the compressive stress begins to decrease due to the effect of stress relaxation. In the third stage, the effect of electromigration increases the compressive stress While the cathodic interface changes from compressive stress to tensile stress. In the fourth stage, the formation of whiskers and hills at the anode releases the compressive stress and the tensile stress at the cathode continues to increase. After the sample was polished, it was found that a uniform thickness of Cu6Sn5 intermetallic compound was formed on the solder joint anode interface.