TY - JOUR
T1 - Effect of rare-earth (La, Ce, and Y) additions on the microstructure and mechanical behavior of Sn-3.9Ag-0.7Cu solder alloy
AU - Dudek, M. A.
AU - Chawla, Nikhilesh
N1 - Funding Information:
The authors gratefully acknowledge financial support for this research from the Semiconductor Research Corporation (SRC) under Contract No. 2005-KJ-1286 (with Drs. M. Renavikar, P. Brofman, K. Zeng, Z. Zhang, and M. Varughese as industrial liaisons). The authors also thank David Wright from the Center for Solid State Science, Arizona State University (Tempe, AZ) for his assistance with evacuating the quartz tubes.
PY - 2010/3
Y1 - 2010/3
N2 - In this article, we report on the microstructure and mechanical properties of Ce- and Y-containing Sn-3.9Ag-0.7Cu solders. The microstructures of both as-processed solder and solder joints containing rare-earth (RE) elements (up to 0.5 wt pct) are more refined compared to conventional Sn-3.9Ag-0.7Cu, with decreases in secondary Sn dendrite size and spacing and a thinner Cu 6Sn5 intermetallic layer at the Cu/solder interface. These results agree well with similar observations seen in La-containing solders reported previously. The monotonic shear behavior of reflowed Sn-3.9Ag-0.7Cu-X(Ce, Y)/Cu lap shear joints was studied as well as the creep behavior at 368 K (95 °C). The data were compared with results obtained for Sn-3.9Ag-0.7Cu and Sn-3.9Ag-0.7Cu-XLa alloys. All RE-containing alloys exhibited creep behavior similar to Sn-3.9Ag-0.7Cu. Alloys with Ce additions exhibited a small decrease in ultimate shear strength but higher elongations compared with Sn-Ag-Cu. Similar observations were seen in La-containing solders. The influence of the RE-containing intermetallics (CeSn3 and YSn3) that form in these alloys on the microstructural refinement, solidification behavior, and mechanical performance of these novel materials is discussed.
AB - In this article, we report on the microstructure and mechanical properties of Ce- and Y-containing Sn-3.9Ag-0.7Cu solders. The microstructures of both as-processed solder and solder joints containing rare-earth (RE) elements (up to 0.5 wt pct) are more refined compared to conventional Sn-3.9Ag-0.7Cu, with decreases in secondary Sn dendrite size and spacing and a thinner Cu 6Sn5 intermetallic layer at the Cu/solder interface. These results agree well with similar observations seen in La-containing solders reported previously. The monotonic shear behavior of reflowed Sn-3.9Ag-0.7Cu-X(Ce, Y)/Cu lap shear joints was studied as well as the creep behavior at 368 K (95 °C). The data were compared with results obtained for Sn-3.9Ag-0.7Cu and Sn-3.9Ag-0.7Cu-XLa alloys. All RE-containing alloys exhibited creep behavior similar to Sn-3.9Ag-0.7Cu. Alloys with Ce additions exhibited a small decrease in ultimate shear strength but higher elongations compared with Sn-Ag-Cu. Similar observations were seen in La-containing solders. The influence of the RE-containing intermetallics (CeSn3 and YSn3) that form in these alloys on the microstructural refinement, solidification behavior, and mechanical performance of these novel materials is discussed.
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U2 - 10.1007/s11661-009-0146-1
DO - 10.1007/s11661-009-0146-1
M3 - Article
AN - SCOPUS:77949289126
SN - 1073-5623
VL - 41
SP - 610
EP - 620
JO - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
JF - Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science
IS - 3
ER -