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Multiferroic Bi_0.95La_0.05Fe_0.7Sc_0.3O₃ (BLFS) thin films with different thicknesses have been prepared on (1 0 0) LaAlO₃ (LAO) substrates using a sol–gel process and annealed in N₂ ambient at 650°C for 5 min. From the X-ray diffraction (XRD) analysis, it was observed that BLFS thin films had (h 0 0)-preferred orientation for the film thickness 63, 125, 186, and 240 nm and became isotropic thereafter. The films developed in-plane epitaxial growth with respect to the substrate. The surface morphology became denser and the surface roughness increased as thickness increased up to 241 nm. The highest dielectric constant observed for the 241 nm thick BLFS film too. No prominent of the leakage current density observed for the film thickness up to 241 nm. However, two fold increase in the leakage current density observed for the film thickness 382 nm. For the BLFS films with thickness 241 nm, we observed the highest dielectric constant (ε) value of 1675 and remnant polarization (P_r) polarization value of 52 μC/cm² using a sol–gel spin coating process.

Bi₄Ti₃O₁₂ (BIT) and Bi₄SrTi₄O₁₅ (BIST) ceramics with particle sizes of approximately 36 and 27 nm, respectively, have been successfully prepared by a new poly(ethylene glycol methacrylate-co-acrylic acid)-based copolymerization method. XRD, FTIR, and Raman investigations on the BIT and BIST samples revealed that the phase pure nanosized ferroelectric samples were obtained relatively at lower temperatures compared to other techniques. The phase transition temperatures and the peak dielectric constant observed at the Curie temperatures for nano-sized BIT and BIST samples obtained in this work are higher than that of conventional ceramic samples with micrometer grain size.

This paper presents the growth of bismuth ferrite (Bi₂Fe₄O₉) thin film by radio frequency magnetron reactive sputtering on p-Si (100) substrate and the characterization of the grown thin film. The deposited thin film is characterized by X-ray diffraction (XRD), field emission scanning electron micrograph (FESEM), energy dispersive X-ray analysis (EDAX), dielectric measurements and vibrating sample magnetometer (VSM) analysis. The XRD study reveals the orthorhombic structure of the crystallites and the particle size is calculated as 45 nm. The FESEM result confirms that the film has smooth surface and uniform distribution of nanoclusters. The percentage of chemical compositions of the film is confirmed by EDAX measurement. The dielectric behavior of the film is examined in terms of the dielectric constant and the dielectric loss as a function of frequency. The magnetic behavior of the film is measured using VSM with the applied magnetic field of about 1 Tesla and the result shows the ferromagnetic behavior of the sample at room temperature.

The electrical and structural properties of titanium oxides TiO₂/TiO_x fabricated by reactive magnetron sputtering were studied and used in a memristor. X-ray diffraction and $I$–$V$ measurements were performed in order to characterize the fabricated structures.