Thin film capacitor structures of Pb(Mg_(1/3)Nb_(2/3))O_3 (PMN)-PbTiO_3 (PT) were fabricated using pulsed laser deposition (PLD) on MgO{100} substrates using (La_(1/2), Sr_(1/2))CoO_3 (LSCO) as a lower electrode. Crystallographic and dielectric characterization confirmed perovskite relaxor-like behaviour. Measurements of the electrostrictive coefficients by insitu X-ray diffraction, piezo-response atomic force microscopy and three point bending experiments showed both Q_(11) and Q_(13) to be comparable to accepted values for single crystals. However, for a given field, the electric field-induced strain in the thin films was much less than that of single crystal. This was clearly intimately like to poor thin film polarisability. Previous work had shown sol-gel PMN-PT films to have significantly greater permittivities than PLD films, and a TEM investigation was undertaken to see if functional differences could be related to differences in microstructue, and hence if the functional and electromechanical properties of PLD films could be improved by attempting to replicate sol-gel microstructures.
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