SEMICONDUCTOR PACKAGE WITH SOLDER BALLS FORMING SECOND NICKEL LAYER ON COPPER LAYER

摘要

PURPOSE: A semiconductor package having solder balls is provided to prevent the decrease of the reliability of a solder joint by forming a second nickel layer on a copper layer. CONSTITUTION: A solder ball(30) comprises sequentially from a plastic core(31) located in the center, a first nickel layer(32), a copper layer(33), a second nickel layer(34) and a solder layer(35). The second nickel layer has the thickness of 1 to 5μm. The second nickel layer is coated on the copper layer by electroless plating, electrolytic plating or hot dipping.