Temporary bonding strength control for self-assembly-based 3D integration

We have demonstrated bonding strength control for self-assembly-based 3D integration in which many chips are instantly assembled on a wafer all at once by using liquid droplets, and then, temporarily bonded to the wafer. The wafer is named Reconfigured Wafer. The self-assembly-based multichip-to-wafer 3D stacking is called reconfigured-wafer-to-wafer 3D integration. The alignment accuracy is found to be within 1 μm and the temporal bonding strength is well controlled by the quality of oxides as a bonding interface material, liquid types (concentration of additives), total bonding area, and surface roughness of the oxides. The self-assembled and temporarily bonded chips are successfully transferred to another wafer in a face-to-face bonding manner in batch processing.