Patent ID: 8191757

Claim:
A method of forming a solder joint, comprising: (a) providing a lead-free, tin-containing solder alloy; (b) providing a printed wiring board substrate or a ball grid array substrate, said substrate being formed from a material comprising copper, and one or more of Ni, Co, Cr, Mn, Zr, Fe and Si and/or alloys thereof, and optionally also zinc; (c) heating the solder alloy; and (d) either before, during or after step (c) contacting the solder alloy with the substrate; wherein said material of the substrate comprises 95 wt % or more Cu and at least one selected from among 0.04 to 5 wt % Zr, 0.04 to 5 wt % Fe, and 0.04 to 5 wt % Si; and wherein the substrate is formed from one of the following alloy compositions (wt. %): Cu-1Zr, Cu-2.35Fe-0.03P-0.12Zn, Cu-1.5Fe-0.18P-0.8Co-0.6Sn, Cu-0.6Fe-0.2P-0.05Mg, Cu-2.8Al-1.8Si-0.4Co, Cu-3.0Ni-0.65Si-0.15Mg, Cu-3.0Si-1.5Sn-0.1Cr.