Ion Beam Assisted Deposition of Ti50Al50N
September 24, 2013 12:00 am
The ion beam assisted sputter deposition (IBSD) technique has been used to deposit TiAlN thin films with the goal of controlling grain structure and thereby optimizing hardness and wear resistance. In the IBSD method the films are deposited using magnetron sputter sources along with a simultaneous argon ion bombardment from an ion gun. The effects of ion bombardment were examined under both acute and oblique angle deposition. The temperature during deposition was 450oC and the substrate bias was constant at -50Vfor all depositions. The films were examined using x-ray diffraction, nano-indentation hardness testing, and atomic force microscopy. For substrates that were stationery during deposition, higher degrees of ion bombardment resulted in grains forming an oblique angle to the substrate. However, for samples rotated during deposition, columnar grains formed normal to the substrate regardless of ion beam flux. The flux of incident ions helped improve the hardness with hardness levels of up to 37 GPa obtained, and also reduce the concentration of voids in the film. X-ray diffraction pole figures showed that the orientation of the grains could be altered using the ion beam assisted process.