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Bi0.9Gd0.1FeO3 (BGFO) thin films were deposited on Pt(111)/Ti/SiO2/Si(100) substrates using the sol-gel method. The thin films showed ferromagnetic properties with remnant magnetization (Mr) of 1.2 emu/g and saturation magnetization (Ms) of 5.3 emu/g. It was found that more than one conduction mechanism is involved in the electric field range used in these experiments. In the low electric field region, the leakage current was controlled by Poole-Frenkel emission. On the other hand, the mechanism can be explained by Schottky emission from the Pt electrode in the high field region.

The Y-doped ZnO nanocrystalline films were deposited on the glass substrates by sol-gel method. X-ray diffraction measurements of the films showed the same wurtzite hexagonal structure and preferential orientation along the c-axis. The grain size of the ZnO films was decreased by the doping of Y. Temperature dependence resistivity showed a semiconductor transport behavior for the nanocrystalline films. At low temperature region, the resistivity can be fitted well with the behavior of Mott variable range hopping, σ(T)=σh0 exp[-(T0/T)n] with n=1/4. On the contrary, at high temperature region, the transport mechanism can be fitted with semiconductor behavior by Arrhenius equation, σ(T)=σ0 exp[-(Ea/kT)m] with m=1. The activation energy Ea is increased from 0.47 meV for nondoped ZnO film to 0.83 meV for Zn0.98Y0.02O film obtained from equation. The results demonstrate that the crystallization and the corresponding carrier transport behavior of the Y-doped ZnO films are affected by the doping of Y.

Bi1-xPrxFe0.95Mn0.05O3 (BPFMO) thin films were successfully deposited on Pt(111)/Ti/SiO2/Si(100) substrates by spin coating with a sol-gel technology and rapid thermal annealing. The effects of Pr content on the microstructure, magnetic and multiferroic properties of thin films were investigated. The result of X-ray diffraction analysis shows that the BPFMO thin films have rhombohedral-to-tetragonal R3c→P4mm phase transition at x = 0.15. The Pr doping on the A-site of BiFeO3 could induce the appearance of the spontaneous magnetization and polarization by the phase transition of rhombohedral-to-tetragonal. The BPFMO thin films with x = 0.2 exhibits the maximum remanent magnetization (2Mr) of 0.44 emu/g.