Multi-chip gang bonding technology using the thermo-compression bonder for Si substrate

Gang bonding process using TCB (thermo-compression bonder) has been developed in recent years as one of the methods to mount advanced packages fast [1, 2]. In the gang bonding process, we can improve the throughput considerably by post-bonding multi pre-bonded chips at a time. However, when a conventional elastic film was used to reduce the variance of bonding load to each chip, we found that the position shift of the chips occurred by deformation of the film especially in narrow pitch chip bonding. In addition, it is difficult to supply enough heat for the solder joint, because the elastic film generally has low thermal conductivity and low heat resistance. In particular, heat capacity necessary for solder fusion is insufficient in the case of chip on wafer (CoW) using Si substrate. In this presentation, we will report about novel gang bonding head (GBH) that is able to reduce the position shift and has both of high thermal conductivity and low elasticity.