Electrical Characteristics and Microstructures of Nd₂O₃-Doped Bi₄Ti₃O₁₂ Thin Films

Nd-doped bismuth titanate and random oriented Bi4-xNdxTi3O12 (BNT) thin films were fabricated on Pt/Ti/SiO2/Si substrates by rf magnetron sputtering technique. These samples had polycrystalline Bi-layered perovskite structure without preferred orientation, and consisted of well developed rod-like grains with random orientation. The remanent polarization (Pr) and coercive field (Ec) of the BNT film with x = 0.5 were above 19 μC/cm2 and 50 KV/cm, respectively. Nd doping into BIT caused a shift of the Curie temperature (TC) of the BIT from 675˚C to 660, 520, 410 and 256oC for the films with x = 0.25, 0.5, 0.75 and 1.0, respectively. The experimental results indicated that Nd doping into BIT result in a remarkable improvement in ferroelectric and dielectric properties.