SELECTIVE INHIBITION FOR SELECTIVE METAL DEPOSITION

A method for processing a substrate includes treating the substrate with a small molecular inhibitor (SMI), the substrate including a recess formed in a dielectric layer and a first metal layer in the recess, the SMI covering a surface of the first metal layer. The method further includes, after treating the substrate with the SMI, treating the substrate with a large molecular inhibitor (LMI), the LMI covering sidewalls of the dielectric layer in the recess. The method further includes heating the substrate to remove the SMI from the first metal layer and to expose the first metal layer in the recess, where the LMI remains on the sidewalls after removing the SMI from the first metal layer. The method further includes depositing a second metal over the first metal layer in the recess, where the LMI covering the sidewalls prevents deposition of the second metal on the dielectric layer.