Nanoindentation response analysis of TiN-Cu coating deposited by magnetron sputtering

To investigate the change of the mechanical properties of soft metals doped PVD (Physical Vapor Deposition) coatings after the migration of soft metal to the surface, TiN-Cu coating was deposited on Si (100) by magnetron sputtering. The microstructure and mechanical properties at room temperature and after vacuum heat treatment at 300 °C were investigated. The results showed that the grains were clustered and the microstructure was porous for TiN-Cu coating at room temperature, while many micro- and nano- sized Cu particles were observed on the surface after vacuum heat treatment at 300 °C. The elastic properties of the TiN-Cu coating after vacuum heat treatment at 300 °C degraded compared with that at room temperature. The hardness and elasticity modulus of TiN-Cu coating kept constant (3.7 GPa and 125.0 GPa, respectively) with the increase of nano-indentation depth, while the hardness and elasticity modulus of TiN-Cu coating after vacuum heat treatment at 300 °C increased gradually.