Ta-based barrier layer improved by plasma immersion ion implantation

Summary form only given. Ta and TaN have been proved to be effective barrier layer materials in copper interconnection. Carbon is implanted into 25 nm Ta and TaN films with different doses by plasma immersion ion implantation (PIII). After annealed under 700/spl deg/C for half an hour, a secondary ion mass spectrometer (SIMS) study shows that, the performance of implanted Ta-based barrier layer is much better than before implanted. Transmission electron microscopy (TEM) investigates the microstructure of samples. Mechanism of this effect is discussed based on detailed comparison between samples with and without PIII.