Patent ID: 8952271
Filing Date: 2015-02-10
Classification: H01L,H05K

Abstract:
1. A method for manufacturing a semiconductor device, the method comprising steps of: forming a first electrode on a first base; and forming a solder ball composed of lead free solder on the first electrode, wherein the step of forming the first electrode comprises steps of: forming a first layer containing copper as a main component on the first base; forming a second layer containing nickel as a main component on the first layer; forming a third layer containing tin as a main component on the second layer; and forming an alloy layer of the second layer and the third layer by a heat treatment after the step of forming the third layer; wherein an alloy of tin, nickel, and copper is formed between the solder ball and the first electrode by the step of the solder ball; and the further comprising a step of connecting the solder ball to a circuit board; wherein the circuit board comprising: a second base; and a second electrode formed on the second base, wherein the second electrode comprising: a fifth layer containing copper as a main component and formed on the second base; a sixth layer containing nickel as a main component and formed on the fifth layer; and a seventh layer containing an alloy of tin and nickel as a main component and formed on the sixth layer.