Patent ID: 8092621

Claim:
A method for inhibiting the growth of a (Ni,Cu) 3 Sn 4 layer at the (Cu,Ni) 6 Sn 5 /nickel interface of a solder joint, comprising: providing a Sn—Ag—Cu solder alloy; and disposing the solder alloy on a surface finish of a soldering pad, wherein a material of the surface finish comprises nickel, and a material of the solder alloy further comprises palladium; and soldering the solder alloy to the surface finish to form a solder joint, wherein a (Cu,Ni) 6 Sn 5 intermetallic layer forms at the solder alloy/nickel interface of the solder joint; and aging the solder joint at temperatures ranging from 100° C. to 180° C., the undesired (Ni,Cu) 3 Sn 4 layer can be inhibited to grow between (Cu,Ni) 6 Sn 5 and nickel.