Direct Plating of Cu on Pd Plasma Enhanced Atomic Layer Deposition Coated TaN Barrier

A method is presented for the direct plating of copper on plasma enhanced atomic layer deposited palladium for ultralarge scale deposition applications. Because copper does not adhere well when electrodeposited directly onto TaN, an additional layer of material is required to act as an adhesion promoter. Atomic force microscopy measurements of the surface roughness showed a surface roughness difference between as-deposited and annealed planar films. The films had a higher resistivity than bulk Cu, but a room-temperature self-anneal of the films resulted in resistivity approximating that of bulk Cu. Scotch tape adhesion measurements for Cu deposits showed good adhesion.