IMC formation on BGA package with Sn–Ag–Cu and Sn–Ag–Cu–Ni–Ge solder balls

Interfacial reactions and mechanical properties between Sn–4.0Ag–0.5Cu and Sn–4.0Ag–0.5Cu–0.05Ni–0.01Ge lead-free solders with the Au/Ni/Cu substrate

“…The k value is increased as the aging temperature is increased in the SACNG/substrate couples. These results are similar to that in the SAC/substrate couples and literature data [25,26]. The IMC evolution in both couples is listed in Table 3.…”

“…Massive research groups have studied interfacial reactions between Sn-Ag and Sn-Ag-Cu alloys with Ni or Cu or Au/Ni/Cu substrates [5,[11][12][13][14][15][16][17][18][19][20][21][22], and several literatures had regarded with interfacial reactions and the mechanical properties of Sn-Ag-Cu alloys by adding a minor amount of Ni or Ge elements to the Au/Ni/Cu substrate [8,21,[24][25][26][27][28][29][30][31]. The Sn-4.0Ag0.5-Cu alloy is one of popular lead-free solders and the Au/Ni/Cu multi-layer is the common UBM structure in electronic packaging.…”

Shear and tensile impact strength of lead-free solder ball grid arrays placed on Ni (P)/Au surface-finished substrates

“…Cu atoms in the SC, SCN and SAC solders arrived at the solder/Ni (P) interface, causing the formation of (Cu,Ni) 6 Sn 5 . Lin and Shih [18] reported that the interface IMC showed hexagonalshaped and whisker-shaped morphology, which were (Cu,Ni) 6 Sn 5 and (Ni,Cu) 3 Sn 4 . The (Ni,Cu) 3 Sn 4 layers were also seen below the (Cu,Ni) 6 Sn 5 in as-reflowed SC, SCN and SAC BGAs in the current study.…”

“…It was reported by Hwang et al that the Ni 3 P layer is not composed of pure Ni 3 P compounds but consisted of Ni 3 P and Ni [17]. Some researchers investigated the relation between the features of these interface IMCs and joint strength [16,18]. In the present study, shear and tensile impact tests were conducted on Sn-Cu, Sn-Cu-Ni, Sn-Ag-Cu and Sn-Pb solder BGA joints placed on Ni (P)/Au surface-finished substrates over a wide range of displacement rates.…”

Pulse Electrodeposition of Lead-Free Tin-Based Composites for Microelectronic Packaging

“…In the present state, the advanced solders that have been developed so far are mostly Sn coupled with other elements like Cu, Ag, Zn, Bi, Sb, Ni. [8][9][10][11][12][13][14] Among all the binary eutectic Pb-free alloys, Sn-Ag, Sn-Zn, and Sn-Cu are considered to be the potential candidates to replace Sn-Pb. For ternary alloys, the most commonly used system is Sn-AgCu which is proved the most effective due to its lower melting temperature and superior mechanical properties compared to the other combinations.…”