Direct Bonding between InP and Gd₃Ga₅O₁₂ for Integrating Semiconductor and Magnetooptic Devices

The bonding of InP/Gd 3 Ga 5 O 12 and InP/GaInSb on Gd 3 Ga 5 O 12 without glue is demonstrated. After chemical treatment, heat treatment in H 2 ambient results in bonding of the samples. We have investigated the bonding conditions, mechanisms and the bonding durability against device fabrication processes. The bonding durability depends on the crystal orientation of the wafer, the heat-treatment temperature and GaInSb layer thickness. The samples bonded at higher temperature maintained bonding after typical device fabrication processes. The (111)-oriented InP is more susceptible to bonding than the (100)-oriented InP. The heat-treatment temperature is reduced by using appropriate chemical treatment and by applying pressure.