Development and process optimization of C2W self-alignment & temporary bonding system

Size-free MEMS-IC integration is important for MEMS ubiquitous applications as well as to reduce its production cost. In our previous work, we have proposed a 2-step approach for MEMS-IC integration by using chip to wafer (C2W) self-alignment and temporary bonding, and then wafer level permanent bonding. In this work, a prototype system for C2W self-alignment and temporary bonding was developed, and the process parameters, e.g. volume of H₂O, wafer temperature, and annealing process, were studied and optimized for better success-ratio and system performance. The results presented in this paper revealed that the proposed system is practically applicable to size-free MEMS-IC integration with reasonably high efficiency.