| 摘要 |
PURPOSE:To prevent the disconnections of inner leads at corner ends on the inside of an inner-lead bonding-side film by notching four corners on the inside of the film and absorbing mechanical stress. CONSTITUTION:Bumps in Au on the nose lower sides of inner leads 15 are thermocompression-bonded with pads 12 for an IC chip 11. The inner leads 15 are weak against mechanical stress because they are thin and long, thus resulting in disconnections due to fatigue of roots in the vicinity of the bondings of the inner leads 15 by expansion and contraction due to heat and expansion and contraction due to moisture absorption of a film 13. The tendency is easy to be generated at each row at the ends of upper and lower, and left and right. Accordingly, when four corners in a window for the film 13 are notched 17, the mechanical stress of the film can be absorbed, thus reducing the disconnections of the inner leads, then largely improving the reliability of a film carrier. |
