SOLDER PASTE AND PRINTED CIRCUIT BOARD

摘要

IN A SOLDER PASTE FORMED BY BLENDING AN ALLOY POWDER AND A FLUX, THE ALLOY POWDER IS A POWDER MIXTURE FORMED BY MIXING AT LEAST ONE POWDER OF A Sn-Zn BASED ALLOY AND AT LEAST ONE POWDER OF A Sn-Ag BASED ALLOY. THE ALLOYS POWDERS ARE BLENDED SO THAT THE COMPOSITION OF THE POWDER MIXTURE IS 5-10 MASS % OF Zn;0.005-1.5 MASS % OF Ag; OPTIONALLY AT LEAST ONE OF 0.002-1.0 MASS % OF Cu, 0.005-15 MASS % OF Bi,0.005-15 MASS OF In, AND 0.005 1.0 MASS OF Sb; AND A REMAINDER OF Sn.