Characterizing metallurgical reaction of Sn3.0Ag0.5Cu composite solder by mechanical alloying with electroless Ni-P/Cu under-bump metallization after various reflow cycles

Interfacial reaction between Sn1Ag0.5Cu(Co) solder and Cu substrate with Au/Ni surface finish during reflow reaction

“…Thus, the phase of this IMC must be (Ni,Cu) 3 Sn 4 that consists of the Ni 3 Sn 4 -crystal structure with 4-7 at.% Cu atoms in the Ni sublattice. Similar analytical results were existed for all other Sn Ag Cu solders, such as Sn 4Ag 0.5Cu, and Sn 3.5Ag 0.7Cu solders joints on the Ni layer [4][5][6][7]. Fig.…”

“…Considerable research on Sn (3-4 wt.%) Ag (0.5-0.75 wt.%) Cu alloys has been carried out, and the interfacial reactions between the solder and substrate have been analyzed to elucidate their interaction [4][5][6][7]. To enhance solder properties and interfacial reactions, microelements, such as Ni, Fe, Mn, Ti and Co have been added to the solder [8][9][10][11][12][13][14][15][16][17].…”

Roles of phosphorous in Sn4Ag0.5Cu solder reaction with electrolytic Ni–Au

“…The results clearly showed that the reaction of P-doped Sn 4 Ag 0.5 Cu with electrolytic Ni/Au could eliminate interfacial nanovoids and that Ni 2 SnP was produced from electroless Ni(P) via the interdiffusion of Ni and Sn [2,3,6,7] but not P. P in the solder reaction appeared to be a passive element. Wang et al [12,13] and Hsiao et al [18] analyzed these two types of compounds in detail. They found that Cu was pinned at the grain boundaries.…”

Inhibiting AuSn4 Formation by Controlling the Interfacial Reaction in Solder Joints

“…This phenomenon was also discussed in the literature. 24,[30][31][32][33][34][36][37][38][39][40] The maximum solubility of IMCs should be associated with the most thermodynamic stable one of an ordered multinary solution phase. In general, the Gibbs free energy of an ordered multinary solution phase is described by: [25][26][27][28][29] …”