The physical properties of cubic plasma-enhanced atomic layer deposition TaN films

The x-ray diffraction, medium energy ion scattering and transmission electron microscopy were used to study the microstructure, conformality, roughness and thermal stability of TaN thin films. The synchrotron x-ray diffraction, optical scattering and sheet resistance measurements during thermal annealing of the test structures were used to study the Cu diffusion barrier properties of plasma-enhanced atomic layer deposition (PE-ALD). It was found that the film microstructure is critical to the diffusion barrier performance. It was also found that grain boundary diffusion is dominating for polycrystalline diffusion barrier failure.