abstract |
A tin alloy electroplating bath, wherein the tin alloy electroplating bath includes (A) a soluble tin salt, (B) a soluble nickel salt and/or a soluble cobalt salt, (C) an oxycarboxylic acid or a salt thereof, (D) a nitrogen-containing heterocyclic unsaturated compound, and (E) a surfactant, and the pH of the tin alloy electroplating bath is 3 to 7. |