| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming an electronic part that has solder bumps with favorable bonding strength on an electrode and solder bumps with favorable bonding strength. SOLUTION: Electrodes 2 to be in conduction with a gold bump 7 of an electronic part 6 with bumps and electrodes 3 to form solder bumps 5 are formed on a substrate 1. Nickel and gold films are successively formed on the electrodes 2 and 3. Before forming solder bumps 5, the thickness of the gold film formed on the electrodes 3 is set within a range where the upper limit is set so that the weight % of gold melted in the solder bumps 5 is 0.1% or less and the lower limit is 0.01μm. Consequently, the amount of gold melted into the solder is limited, and solder bumps 5 with favorable bonding strength can be formed because production of a fragile compound of gold and tin is restricted in the solder bumps 5. |
