Patent ID: 8887980
Filing Date: 2014-11-18
Classification: B23K,H05K

Abstract:
1. A soldering method comprising performing soldering of a solder ball which has a diameter of 0.04-1.0 mm and is made from a lead-free solder consisting of Ag: 1.0-4.0 mass percent, Cu: 0.1-1.0 mass percent, P: 0.03-0.08 mass percent, Ni: 0-1 mass percent, In: 0-15 mass percent, and a remainder of Sn to a plated portion which is plated by electroless Ni plating to form a solder bump and a SnNi intermetallic compound layer between the solder bump and the plated portion, the SnNi intermetallic compound layer having a thickness of at most 0.5 μm.