Electronic devices having bilayer capping layers and/or barrier layers

An electronic device comprising:

• a substrate;
• and
• a conductive feature disposed over the substrate, the conductive feature comprising:
• (a) disposed over the substrate, a conductor layer comprising at least one of Cu, Ag, Al, or Au, and
• (b) disposed over the conductor layer, a bilayer capping layer comprising a base layer and a dielectric layer disposed thereover, wherein (i) the base layer comprises an alloy of Cu and/or Mo with 0.5 weight %-50 weight % of one or more anodizable alloying elements selected from the list consisting of Ta, Nb, Al, Hf, Zr, Ti, and Mg, and (ii) the dielectric layer comprises an oxide, nitride, or oxynitride of the one or more anodizable alloying elements.