A first bond pad of a first device and a second bond pad of a second device are implanted with metal ions. The first and second semiconductor device are bonded together using a direct metal-to-metal bond and an overlay offset occurs between the bond pads such that a portion of the first bond pad and a portion of the second bond pad overlaps and contacts a dielectric material layer. During the bonding process, however, diffusion of the metal ions provides a barrier layer at the interface of the bond pads and the dielectric layers.

Improved bonding surfaces for microelectronics are provided. An example method of protecting a dielectric surface for direct bonding during a microelectronics fabrication process includes overfilling cavities and trenches in the dielectric surface with a temporary filler that has an approximately equal chemical and mechanical resistance to a chemical-mechanical planarization (CMP) process as the dielectric bonding surface. The CMP process is applied to the temporary filler to flatten the temporary filler down to the dielectric bonding surface. The temporary filler is then removed with an etchant that is selective to the temporary filler, but nonreactive toward the dielectric surface and toward inner surfaces of the cavities and trenches in the dielectric bonding surface. Edges of the cavities remain sharp, which minimizes oxide artifacts, strengthens the direct bond, and reduces the bonding seam.