TaCN growth with PDMAT and H2/Ar plasma by plasma enhanced atomic layer deposition

TaCN films were deposited using atomic layer deposition (ALD) using PDMAT and H2/Ar plasma. Calculations based on density functional theory (DFT) indicate a high energy barrier and a low reaction energy for reducing the +5 Ta oxidation state in the PDMAT precursor by using pure H radicals. Through the assistance of Ar radicals, low resistivity of TaCN films of 230 μΩ cm could be deposited by using H2/Ar plasma. By employing in situ X-ray diffraction during annealing, the activation energy for Cu diffusion through the TaCN barrier was evaluated at 1.6 eV.