Methods of fabricating electronic devices using direct copper plating

A method of manufacturing a semiconductor device having copper metallization, the method comprising:

• providing a patterned semiconductor device wafer;
• using atomic layer deposition to deposit a tantalum nitride diffusion barrier for copper;
• treating the barrier layer surface in a hydrogen containing plasma;
• depositing a ruthenium seed layer by atomic layer deposition to form a conformal portion of the seed layer and chemical vapor deposition to form a nonconformal portion of the seed layer so that the seed layer is effective for direct electrochemical deposition of gapfill copper;
• and
• electroplating a copper gapfill layer onto the ruthenium seed layer.

A semiconductor device having copper metallization made using a method comprising:

• providing a patterned wafer having a diffusion barrier for copper;
• depositing a copperless seed layer on the diffusion barrier effective for direct electrochemical deposition of gapfill copper, the seed layer being formed by a conformal deposition process and by a nonconformal deposition process;
• and
• electroplating copper gapfill onto the seed layer.