Advanced Solder Alloys For Electronic Interconnects

A lead-free, solder alloy comprising:

• (a) 10 wt. % or less of silver
• (b) 10 wt. % or less of bismuth
• (c) 3 wt. % or less of copper
• (d) 4 wt % or less of antimony
• (e) at least one of the following elements
• up to 1 wt % of Ni
• up to 1 wt. % of titanium
• up to 1 wt. % of cobalt
• up to 3.5 wt. % of indium
• up to 1 wt. % of zinc
• up to 1 wt. % of cerium
• (f) optionally one or more of the following elements
• 0 to 1 wt. % of manganese
• 0 to 1 wt. % of chromium
• 0 to 1 wt. % of germanium
• 0 to 1 wt. % of iron
• 0 to 1 wt. % of aluminum
• 0 to 1 wt. % of phosphorus
• 0 to 1 wt. % of gold
• 0 to 1 wt. % of gallium
• 0 to 1 wt. % of tellurium
• 0 to 1 wt. % of selenium
• 0 to 1 wt. % of calcium
• 0 to 1 wt. % of vanadium
• 0 to 1 wt. % of molybdenum
• 0 to 1 wt. % of platinum
• 0 to 1 wt. % of magnesium
• 0 to 1 wt. % of rare earths
• (g) the balance tin, together with any unavoidable impurities.

A soldered joint comprising a lead-free solder alloy comprising:

• (a) 10 wt. % or less of silver
• (b) 10 wt. % or less of bismuth
• (c) 3 wt. % or less of copper
• (d) 4 wt. % or less of antimony
• (e) at least one of the following elements
• up to 1 wt. % of nickel
• up to 1 wt. % of titanium
• up to 1 wt. % of cobalt
• up to 3.5 wt. % of indium
• up to 1 wt. % of zinc
• up to 1 wt. % of cerium
• (f) optionally one or more of the following elements
• 0 to 1 wt. % of manganese
• 0 to 1 wt. % of chromium
• 0 to 1 wt. % of germanium
• 0 to 1 wt. % of iron
• 0 to 1 wt. % of aluminum
• 0 to 1 wt. % of phosphorus
• 0 to 1 wt. % of gold
• 0 to 1 wt. % of gallium
• 0 to 1 wt. % of tellurium
• 0 to 1 wt. % of selenium
• 0 to 1 wt. % of calcium
• 0 to 1 wt. % of vanadium
• 0 to 1 wt. % of molybdenum
• 0 to 1 wt. % of platinum
• 0 to 1 wt. % of magnesium
• 0 to 1 wt. % of rare earths
• (g) the balance tin, together with any unavoidable impurities.