Effects of Co additions on electromigration behaviors in Sn–3.0 Ag–0.5 Cu-based solder joint

Crystallographic Characteristic Effect of Cu Substrate on Serrated Cathode Dissolution in Cu/Sn–3.0Ag–0.5Cu/Cu Solder Joints during Electromigration

“…This has also been proven in a previous study looking at the IMC growth in idealized single-crystal joints using Sn-3.0Ag-0.5Cu (SAC305) solder alloy [13]. Additionally, the rapid diffusion of Cu atoms at the boundary groove also leads to the nonuniform consumption of Cu substrate and the serrated cathode interface [15,20]. Some studies further revealed that the c axis of Sn grain dominated the dissolution of Cu substrate (or Ni substrate) and the second phase Cu 6 Sn 5 during EM [18,19,[25][26][27].…”

“…Hence, EM-induced failure has been widely researched. The failure mechanisms of solder joints induced by EM are extensively studied and many results have been obtained [14][15][16][17], and one of the most well-known results is that when the c-axis of β-Sn grains, which usually refers to the Sn grain orientation, is aligned or nearly aligned along the current direction, the Cu atoms diffuse quickly and the EM deterioration is more serious [18,19].…”

“…Recently, it has been reported that the current density over 5 × 10 3 A/cm 2 may induce the cathode dissolution of the interfacial IMC and Cu substrate, and some investigations reveal that the dissolution of the IMC is very complicated and closely related to two factors: the anisotropy of β-Sn grains and the unstable grain boundary grooves between interfacial Cu 6 Sn 5 grains [15,[20][21][22][23][24]. When the c-axis of β-Sn grains is aligned or near-aligned to the current direction in line-type Cu/Sn/Cu interconnects, the diffusion of Cu atoms is fast and, consequently, the IMC dissolution becomes more severe [23].…”

Dominant effects of Sn orientation on serrated cathode dissolution and resulting failure in actual solder joints under electromigration

“…The rapid diffusion of Cu away from the cathode leads to the excess dissolution of intermetallic compounds and the cathode material [3,4]. Excessive dissolution of the cathode frequently leads to a distinctive serrated interface, with most of the serrated teeth inclined toward a specific direction [5][6][7][8][9][10][11]. The sequence of events in the early stage has previously been described in detail, and the initiation of the formation of the serrated interface has been shown to be related to preferential dissolution at the Cu 6 Sn 5 grain boundaries [5].…”

Thermo-migration behavior of SAC305 lead-free solder reinforced with fullerene nanoparticles

“…According to previous studies, mechanical properties and solderability of existing lead-free solders could be improved by adding some foreign reinforcement (including metals, ceramics, and carbonbased materials) into a solder matrix to prepare a composite solder [16][17][18][19][20][21]. In addition, some researchers also attempted to investigate an effect of foreign reinforcement on EM in solder joints; it was reported that a suitable type and an appropriate amount of reinforcement added showed a positive effect on suppressing EM in solder joints [22][23][24][25][26][27]. However, to date, a systematic study of TM behavior of composite solder interconnections containing foreign reinforcement under large temperature gradient is still lacking.…”