Low temperature bonding for 3D

Chemical interactions exist always between atoms on mated solids as the nature of solid surface. These interactions are origin of the adhesion energy between solids. It means that any solid materials should be bonded even if there is neither high temperature reaction nor diffusion process. This is the idea on which the surface activated bonding (SAB) at room temperature is based. Recent development of the SAB combining several processes of the surface activation provides a bridge to the conventional wafer bonding technique for bonding in ambient atmosphere.