Plasma activation assisted low-temperature direct wafer bonding

We report our latest activities of low-temperature III/V-to-Si direct wafer bonding assisted by chemical-mechanical polishing (CMP) and O2 plasma activation. We show here the optimized process flow for fusion bonding of InP epitaxial wafers and dies onto silicon (Si) substrate covered with oxide layer of varying thickness. High yield and low cost die-to-wafer bonding is achievable in the near future.