电迁移作用下的微焊点振动疲劳行为研究

Study on vibration fatigue behavior of microscale solder joints under electromigration conditions

研究了不同电迁移时间（0～96 h）和电流密度（0～1.52×104 A/cm2）对Sn-3.0Ag-0.5Cu微焊点振动疲劳行为的影响。结果显示,在电迁移时间和电流密度均为0时,微焊点的振动疲劳循环次数大于1 170次,疲劳寿命大于234 min;而在125℃服役温度下,当振动频率为0.8 Hz,交变应力为0～20 MPa,电流密度为1.52×104 A/cm2,微焊点电迁移96 h后其振动疲劳循环次数仅为96次,疲劳寿命仅19.2 min。研究表明,微焊点的振动疲劳失效实际上为复杂的振动疲劳与蠕变共同作用下的变形过程。

Influences of different electromigration times（0-96 h） and current densities（0-1.52×104 A/cm2） on the vibration fatigue behavior of microscale Sn-3.0Ag-0.5Cu solder joints were studied.The results show that the cycle number of solder joints in vibration fatigue test is more than 1 170 times and fatigue life is longer than 234 min with no electromigration.However,cycle number of solder joints in vibration fatigue test is only 96 times,and fatigue life is only 19.2 min with the current density of 1.52×104 A/cm2 and electromigration time of 96 h.The study shows that the failure of microscale solder joints is also a complicated course of co-action of vibration fatigue and creep deformation.