增强相对无铅焊点电迁移行为影响的研究

he requirements of miniaturization and multifunctional for microelectronic devices lead to the current density which imposes on the solder joint continuous increase. Therefore, electromigration (EM) is becoming a standout reliability issue for lead-free solder. Structural optimization and material modification are considered to be the possible methods for alleviating EM damage. This study investigates the impact of 0.2wt.% Co additions and in-situ 5vol.% Cu6Sn5 , which were introdued into solder matrix by alloying and fabricating composite solder approaches respectively, on electromigration from the perspective of material modification. The results indicated that both 0.2wt.% Co and in-situ 5vol.% Cu6Sn5 played an effective role in inhibiting EM behavior. Co element additions made Ag3Sn intermetallic compounds disperse homogeneously in solder matrix and as a barrier to Cu atoms diffusion. Moreover, (Cu, Co)6Sn5 phase migration was pinned by Co addition. In-situ Cu6Sn5 phase suppressed EM by changing the chemical concentration gradient of Cu atoms at the interface.