Mechanical behaviour of ferroelectric films on perovskite substrate

This paper is focused on the mechanical behaviour of single and multilayered ceramic systems on ceramic substrate. The ferroelectric ceramic PLT (Pb0.9La0.1TiO3) was deposited using magnetron sputtering on (001) STO (SrTiO3) and on a YBCO (YBa2Cu3O7), as a 200 nm interlayer on STO. DRX and SEM observations were carried out to determine the microstructure of the various films, and TEM cross sections were realised to control the film thickness and grain epitaxial relationships. AFM was used as a roughness controller before and after deposition. Mechanical properties of the films and substrate were determined using micro and nanoindentation tests. Young’s modulus and hardness of each system (STO, PLT/STO, YBCO/STO, PLT/YBCO/STO) were calculated and a peculiar phenomenon, associated to the YBCO interlayer addition, was observed. This work shows that YBCO improve mechanical properties of multilayered ceramics.