Elastic and plastic energies in sputtered multilayered Ti-TiN films estimated by nanoindentation

Energetic parameters for describing mechanical properties, which makes it possible to discuss deformation behavior of a film elastically and plastically, are presented. Elastic energy and dissipated energy estimated from the area surrounded by a load-displacement curve obtained by nanoindentation measurement indicate the energy to deform a film elastically and plastically. The energy dissipated ratio defined as the ratio of dissipated energy to total applied energy to a film indicates the tendency for plastic deformation of a film. By considering the two energies and the energy dissipated ratio, deformation behavior of compositionally modulated Ti-TiN films with a multilayered structure was examined. At a modulation period of 10 nm, the reduction of the dissipated energy and the energy dissipated ratio were observed. Since the dissipated energy is consistent with energy for the propagation of the dislocations related to plastic deformation, it was assumed that the reduction was caused by a pinning effect for the propagation of the dislocations at interfaces of Ti and TiN. (C) 2000 Elsevier Science S.A. All rights reserved.