Effects of Sn-Cu-Ni-Ce solder on mechanical properties of micro- joints soldered with diode-laser soldering system

The properties of micro-joints of two kinds of components devices QFP48 and rectangular chip component 0805 were studied with Sn-Cu-Ni-Ce lead-free solder by means of diode-laser soldering system and infrared reflow soldering method reflow soldering method, and the distribution regulations of the mechanical properties of quad flat packaging and rectangular chip component soldered with different compositional solders were tested and analyzed by STR- 1000 micro-joints tester.The results indicate that optimal laser output current while soldering with Sn-Cu-Ni-Ce solder is obviously larger than that of soldering with Sn-Ag-Cu solder or Sn-Pb solder respectively.The mechanical properties of micro-joints soldered with laser soldering system is notability larger than that of micro-joints soldered with IR reflow soldering method.Adding rare earth element Ce to Sn-Cu-Ni lead-free solder is able to improve the mechanical properties of the micro-joints which the mechanical properties of micro- joints is the best when the content of Ce is about 0.03wt.%.