Effect of Cu damascene metallization on gate SiO2 plasma damage

The effect of using a Cu damascene process on plasma process-induced damage (PPID) is studied in relationship to future scaling rules. Wafers processed using: a Cu damascene metallization scheme show little increase in gate leakage as antenna ratios are increased. This is contrasted to conventional Al wafers, which show a significant increase in the gate leakage as the antenna ratio is increased. Applying this result to future technology generations shows that wafers produced with a Cu damascene process have the potential to exhibit significantly less gale leakage for future technology generations.