A method of sealing a first wafer and a second wafer each made of semiconducting materials, including: implanting a metallic species in at least the first wafer, assembling the first wafer and the second wafer by molecular bonding, and after the molecular bonding, forming a metallic ohmic contact including alloys formed between the implanted metallic species and the semiconducting materials of the first wafer and the second wafer, the metallic ohmic contact being formed at an assembly interface between the first wafer and the second wafer, wherein the forming includes causing the implanted metallic species to diffuse towards the interface between the first wafer with the second wafer and beyond the interface.