Abstract
Ion-Beam-Assisted Deposition (IBAD) method has been employed to grow nanocrystalline titanium nitride (TiN), vanadium nitride (VN) and chromium nitride (CrN) thin films of approximately 200-500 nm in thickness with either nano-columnar or nano-equiaxed structure. Processing variables include substrate temperature (150 C to 500 C), the nitrogen ion beam energy (200eV, 350eV and 500eV) and the incident angle (45 and 0 degree). Variation of preferred orientation (texture) was measured under different deposition conditions. Film microstructure as well as nano-hardness values were investigated. A systematic study was carried out to understand the relationship of texture (both out-of-plane and in-plane) development and deposition condition. A model is proposed to explain the texture, which involves a combination of energetic considerations including ion sputtering/channeling effect, surface energy, and film stress. Nano-hardness values are also explained using grain boundary sliding and rotation mechanisms, as opposed to the traditional dislocation-driven plastic deformation.
