Room temperature GaN bonding by surface activated bonding methods

In this work, both GaN-Si and GaN-diamond bonding at room temperature were achieved by surface activated bonding (SAB) methods. In the GaN-Si bonding by standard SAB, the results of Ga-face to Si bonding are better than that of N-face to Si bonding such as higher bonding energy. Both of the structure and composition of the two kinds of GaN-Si interfaces were investigated to understand the bonding mechanisms. In the GaN-diamond bonding by modified SAB using an intermediate Si nano-layer, a uniformly seamless bonding interface was achieved. The GaN-diamond bonded structure is expected to be helpful for the applications of high-power GaN devices.