Industrial interest, political pressure: two major reasons for the synthesis of unleaded piezoelectric thin layers with high performances have become an important research topic. The objective of this work is the synthesis and characterization of a promising material: NBT. The development of NBT thin films by rf-magnetron sputtering was optimized. The study shows that annealing at 675°C under oxygen allows better crystallization of NBT. Electrical characterizations showed good dielectric, ferroelectric and piezoelectric properties. Polarization and displacement values obtained by applying an electric field are remarkable. However, values of remnant polarization are low. The temperature study was used to determine phase transitions and highlighted the relaxor character of NBT. The mixture of BT with the NBT in a solid solution should improve the electrical performances. Leakage currents caused the opposite effect, that is to say, a degradation of the properties of our thin films.
