Mechanical properties measured by nano-indentation of Pb(Zr, Ti)03 sol–gel films deposited on Pt and LaNi03 electrodes

The crystallographic orientation of PZT films is related to the orientation of the substrate (electrode) and the process parameters. In this study, the PZT films are deposited by sol–gel on silicon substrate with different bottom electrodes: TiOx/Pt and LaNiO3. In terms of sol–gel process we have modified the precursor concentration and the type of solvent. All these parameters affect the crystallite orientation. Nano-indentation tests coupled with continuous stiffness measurements allowed to obtain the M<hkl> elastic modulus and the hardness Hb<hkl> of these films. From the present study and from the literature, it is clearly shown that the mechanical properties greatly depend on the crystalline orientation. A compilation of all the reported data allows us to propose the values of M<hkl> and Hb<hkl> for the three characteristic orientations (001), (111) and (110).