| 摘要 |
<p>Provided is a solder ball that suppresses interfacial peeling at the bonding interface of the solder ball and suppresses non-fusion that occurs between the solder ball and a solder paste. The solder ball can be used for both a Ni electrode section having Au plating or the like, and a Cu electrode section having a water-soluble organic solderability preservative coated on Cu. This invention pertains to a lead-free solder ball for electrodes for BGA and CSP, having 1.6-2.9 mass pcnt Ag, 0.7-0.8 mass pcnt Cu, 0.05-0.08 mass pcnt Ni, and the remainder comprising Sn. The lead-free solder ball has both excellent heat fatigue resistance and excellent drop impact resistance, even when the bonded printed circuit board is a Cu electrode or is a Ni electrode using Au plating or Au/Pd plating in the surface treatment thereof. In addition, a total of 0.003-0.1 mass pcnt of at least one type of element selected from among Fe, Co, and Pt or a total of 0.003-0.1 mass pcnt of at least one type of element selected from Bi, In, Sb, P, and Ge can be added to this composition.</p> |
