Aging Characteristics of Sn-Ag Eutectic Solder Alloy with the Addition of Cu, In, and Mn

作者：Ghosh M^*; Kar Abhijit; Das S K; Ray A K

来源：Metallurgical and Materials Transactions A-Physical Metallurgy and Materials Science, 2009, 40A(10): 2369-2376.

DOI：10.1007/s11661-009-9948-4

In the present investigation, three types of solder alloy, i.e., Sn-Ag-Cu, Sn-Ag-In, and Sn-Ag-Cu-Mn, have been prepared and joined with Cu substrate. In the reflowed condition, the joint interface is decorated with Cu(6)Sn(5) intermetallic in all cases. During aging at 100 A degrees C for 50 to 200 hours, Cu(3)Sn formation took place in the diffusion zone of the Sn-Ag-Cu and Sn-Ag-In vs Cu assembly, which was not observed for the Sn-Ag-Cu-Mn vs Cu joint. Aging also leads to enhancement in the width of reaction layers; however, the growth is sluggish (similar to 134 KJ/mol) for the Sn-Ag-Cu-Mn vs Cu transition joint. In the reflowed condition, the highest shear strength is obtained for the Sn-Ag-Cu-Mn vs Cu joint. Increment in aging time results in decrement in shear strength of the assemblies; yet small reduction is observed for the Sn-Ag-Cu-Mn vs Cu joint. The presence of Mn in the solder alloy is responsible for the difference in microstructure of the Sn-Ag-Cu-Mn solder alloy vs Cu assembly in the reflowed condition, which in turn influences the microstructure of the same after aging with respect to others.

• 出版日期2009-10