| 摘要 |
PURPOSE:To provide a solder bump electrode which is less deteriorated in bonding strength even if a reflow process is carried out at a temperature of 350 deg.C dispensing with a process in which a film is formed on an Al electrode when a solder bump on an IC chip Al electrode is subjected to a reflow process. CONSTITUTION:A solder wire is composed of two car more kinds of elements selected out of Cu (0. 01 to 5.0weight%), Ni (0.01 to 5.0weight%), and Zn (0. 01 to 5.0weight%), 0. 01 to 1. 0% Ti by weight, and Sn or Pb-Sn as the rest, solder bumps 3 made of the above solder wire are formed on Al electrodes 2 provided onto an IC chip 1, and the electrodes 2 and 5 of the IC chip 1 and a board 4 are bonded together through the intermediary of the solder bumps 3. At this point, the solder bumps 3 are subjected to a reflow process at a temperature of 350 deg.C to correct the electrodes 2 and 5 for misalignment with each other, whereby the IC chip 1 and the board 4 are protected against bonding failure. The solder bump 3 is less deteriorated in shear strength even if it is subjected to a reflow process and kept high enough in shear strength for a practical use. |
