Analysis of Basic Properties and Bonding Properties of Various Melting Temperature Solders

The basic properties and bonding characteristics of SAC305, Sn-Bi, and Sn-Ag-In-Bi solders with different melting points were evaluated. In test results, SAC305 had a melting point of about 217°C, Sn-Bi was about 140°C and Sn-Ag-In-Bi was about 170 to 190°C. These solder showed different ball surface and hardness values based on solder composition. And Sn-Bi solder showed higher ball shear strength than SAC305 and Sn-Ag-In-Bi in Cu-OSP pad finish bonding. But three solder showed almost same ball shear strength in Ni/Au pad finish bonding.