The influences of substrate and annealing temperatures on the characteristics of SrBi4Ti4O15 thin films

The radio frequency (RF) sputtering is used as the method and the layer structured bismuth compound of SrBi₄Ti₄O₁₅ + 4 wt% Bi₂O₃ ferroelectric ceramic is used as the target to deposit SrBi₄Ti₄O₁₅ thin films. The excess Bi₂O₃ content is used to compensate the vaporization of Bi₂O₃ during the depositing process. SrBi₄Ti₄O₁₅ (SBT) ferroelectric thin films are deposited on Pt/Ti/SiO₂/Si under optimal RF magnetron sputtering parameters with different substrate temperatures for 2 h, after that the SBT thin films are post-heated using rapid temperature annealing (RTA) method. The dielectric and electrical characteristics of SBT thin films are measured using metal-ferroelectric-metal (MFM) structure. From the physical and electrical measurements of X-ray diffraction patterns, scanning electronic microscope (SEM), I-V curves and C-V curves, the substrate temperatures and RTA-treated temperatures have large influences on the morphologies, the crystal structures, the leakage current densities and the dielectric constants of SBT thin films.