US Patent 10141260 Interconnection structure and method for forming the same

A method of forming an interconnection structure includes forming a dielectric structure over a non-insulator structure; forming a hole in the dielectric structure to expose the non-insulator structure; forming a first diffusion barrier layer into the hole in the dielectric structure using a first deposition process; forming a second diffusion barrier layer over the first diffusion barrier layer using a second deposition process that is different from the first deposition process; and forming a metal over the second diffusion barrier layer.