Diffusion barrier layers

Provided are methods and apparatuses for depositing barrier layers for blocking diffusion of conductive materials from conductive lines into dielectric materials in integrated circuits. The barrier layer may contain copper. In some embodiments, the layers have conductivity sufficient for direct electroplating of conductive materials without needing intermediate seed layers. Such barrier layers may be used with circuits lines that are less than 65 nm wide and, in certain embodiments, less than 40 nm wide. The barrier layer may be passivated to form easily removable layers including sulfides, selenides, and/or tellurides of the materials in the layer.