TY - JOUR
T1 - Wetting and reaction of Sn-2.8Ag-0.5Cu-1.0Bi solder with Cu and Ni substrates
AU - Rizvi, M. J.
AU - Chan, Y. C.
AU - Bailey, C.
AU - Lu, H.
AU - Islam, M. N.
AU - Wu, B. Y.
PY - 2005/8
Y1 - 2005/8
N2 - The wettability of newly developed Sn-2.8Ag-0.5Cu-1.0Bi lead-free solder on Cu and Ni substrates was assessed through the wetting balance tests. The wettability assessment parameters such as contact angle (θc) and maximum wetting force (Fw) were documented for three solder bath temperatures with three commercial fluxes, namely, no-clean (NC), nonactivated (R), and watersoluble organic acid flux (WS). It was found that the lead-free Sn-2.8Ag-0.5Cu1.0Bi solder exhibited less wetting force, i.e., poorer wettability, than the conventional Sn-37Pb solder for all flux types and solder bath temperatures. The wettability of Sn-2.8Ag-0.5Cu-1.0Bi lead-free solder on Cu substrate was much higher than that on Ni substrate. Nonwetting for Sn-2.8Ag-0.5Cu-1.0Bi and Sn-Pb solders on Ni substrate occurred when R-type flux was used. A model was built and simulations were performed for the wetting balance test. The simulation results were found very close to the experimental results. It was also observed that larger values of immersion depth resulted in a decrease of the wetting force and corresponding meniscus height, whereas the increase in substrate perimeter enhanced the wettability. The wetting reactions between the solder and Cu/Ni substrates were also investigated, and it was found that Cu atoms diffused into the solder through the intermetallic compounds (IMCs) much faster than did the Ni atoms. Rapid formation of IMCs inhibited the wettability of Sn-2.8Ag-0.5Cu-1.0Bi solder compared to the Sn-Pb solder.
AB - The wettability of newly developed Sn-2.8Ag-0.5Cu-1.0Bi lead-free solder on Cu and Ni substrates was assessed through the wetting balance tests. The wettability assessment parameters such as contact angle (θc) and maximum wetting force (Fw) were documented for three solder bath temperatures with three commercial fluxes, namely, no-clean (NC), nonactivated (R), and watersoluble organic acid flux (WS). It was found that the lead-free Sn-2.8Ag-0.5Cu1.0Bi solder exhibited less wetting force, i.e., poorer wettability, than the conventional Sn-37Pb solder for all flux types and solder bath temperatures. The wettability of Sn-2.8Ag-0.5Cu-1.0Bi lead-free solder on Cu substrate was much higher than that on Ni substrate. Nonwetting for Sn-2.8Ag-0.5Cu-1.0Bi and Sn-Pb solders on Ni substrate occurred when R-type flux was used. A model was built and simulations were performed for the wetting balance test. The simulation results were found very close to the experimental results. It was also observed that larger values of immersion depth resulted in a decrease of the wetting force and corresponding meniscus height, whereas the increase in substrate perimeter enhanced the wettability. The wetting reactions between the solder and Cu/Ni substrates were also investigated, and it was found that Cu atoms diffused into the solder through the intermetallic compounds (IMCs) much faster than did the Ni atoms. Rapid formation of IMCs inhibited the wettability of Sn-2.8Ag-0.5Cu-1.0Bi solder compared to the Sn-Pb solder.
KW - Contact angle
KW - Finite element modeling
KW - Flux
KW - Intermetallic compounds
KW - Sn-2.8Ag-0.5Cu-1.0Bi
KW - Surface tension
KW - Wettability
KW - Wetting force
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UR - https://www.scopus.com/record/pubmetrics.uri?eid=2-s2.0-24144493837&origin=recordpage
U2 - 10.1007/s11664-005-0239-6
DO - 10.1007/s11664-005-0239-6
M3 - RGC 21 - Publication in refereed journal
SN - 0361-5235
VL - 34
SP - 1115
EP - 1122
JO - Journal of Electronic Materials
JF - Journal of Electronic Materials
IS - 8
ER -