The present invention provides a method for improving the adhesion of copper and other metal-comprising conductive metals to a barrier layer. A barrier layer is provided that has a first surface that is substantially unoxidized, wherein at least a portion of the first surface is free from the presence of oxygen atoms. A conductive layer is then deposited onto the first surface of the barrier layer. The substantially unoxidized state of the first surface enhances the adhesion of the metal-comprising layer to the barrier layer. The method is particularly useful in obtaining excellent adhesion of a copper nucleation layer to an underlying barrier layer surface.