Selective inhibition for selective metal deposition

A method for processing a substrate, the method comprising:

• performing a cyclic chemical vapor deposition (CVD) process, the substrate comprising a dielectric layer having a recess and a first metal layer at a bottom of the recess, one cycle of the cyclic CVD process comprising:
• treating the substrate with a small molecular inhibitor (SMI), the SMI selectively adsorbed on the first metal layer and covering a surface of a second metal formed over the first metal layer;
• after treating the substrate with the SMI, treating the substrate with a large molecular inhibitor (LMI), the LMI selectively adsorbed over the dielectric layer and covering sidewalls of the dielectric layer in the recess, the LMI having a greater molecular weight or molecular volume than the SMI;
• heating the substrate to remove the SMI from over the second metal and to expose the second metal, wherein the LMI remains on the sidewalls;
• and
• depositing the second metal over the first metal layer in the recess, wherein the LMI covering the sidewalls prevents deposition of the second metal on the dielectric layer.

A method for processing a substrate, the method comprising:

• exposing the substrate to a first vapor comprising a small molecular inhibitor (SMI), the substrate comprising a dielectric surface and a first metal surface, the SMI adsorbing on the first metal surface selectively to the dielectric surface;
• exposing the substrate to a second vapor comprising a large molecular inhibitor (LMI), the LMI selectively adsorbing on the dielectric surface, the adsorbed SMI preventing the LMI from adsorbing on the first metal surface;
• removing the SMI from the first metal surface without removing the LMI from the dielectric surface;
• and
• depositing a second metal over the first metal surface by chemical vapor deposition (CVD), wherein a deposition rate over the first metal surface is at least 100 times as high as a deposition rate over the dielectric surface.