4328 Study on High Reliable Cu-bump Joint
Details
The structural reliability for Cu-bump joint was studied analytically by using a design of experiments. Moreover, the influence of mechanical property of underfill resin on the fatigue life of Cu-bump interconnect under the thermal cycle test was also studied. In conclusion, it was found that the thermal stress at the interface between the Cu-bump and the UBM increases as the increase in thickness and length of Cu-bump. The interface stress especially depends on the length of Cu-bump. The length of Cu-bump was thus important design factor to be compatible both the joint reliability and the highly heat dissipation. It was also found that the existing mechanical property of underfill resin for solder-bump joint was appropriate for Cu-bump joint connected to the substrate using solder.
