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Ferroelectric Bi4Ti3O12 thin films were prepared by metalorganic decomposition (MOD) using titanium butoxide and bismuth nitrate. Multi-layer thin films were spin coated and pre-fired at 350 and 450d`C for 30 min, respectively. The influence of pre-firing process on the structural and electric properties were characterized by differential thermal analyses (DTA), X-ray diffraction (XRD). dielectric and ferroelectric analyses. In comparison with the two pre-fired samples for the same film thickness (0.86 μm) and same annealing temperature (600d`C for 30 min) we got non-crystalline and crystalline thin films for pre-fired at 350d`C and 450d`C respectively. The grain size and mode value of internal strain (pressed), calculated by Hall method from the shift and broadening of the XRD peaks, in Bi4Ti3O12 thin films pre-fired at 350d`C were smaller than that pre-fired at 450d`C The dielectric constants of the films pre-fired at 350d`C were smaller than that pre-fired at 450d`C. The coercive field, spontaneous polarization of the films pre-fired at 350d`C were greater than that pre-fired at 450d`C. The dielectric and ferroelectric properties were discussed by the grain size effect and internal strain effect.

Structures and properties of Pb(Zr0.5Ti0.5)O3 thin films by metallo-organic compound decomposition (MOD) process have been investigated. PZT thin films with thickness of 0.6 μml m were deposited by repeating spin-coating precursor solutions and thermal annealing steps on sapphires and (111) Si wafers with or without an Al2O3 buffer layer and a bottom platinum electrode. The structures and morphologies of the PZT films are affected strongly by thermal treatment and substrates. PZT films have good dielectric-frequency characteristics, and their dielectric constant and loss tangent are 480 and 1.1% at 1 kHz respectively. PZT films with remnant polarization Pr of 11.4 μml C/cm2 and coercive field Ec of 80 kV/cm have been obtained