Anisotropic ferroelectric properties of MOD-derived Bi_3.25Nd_0.75Ti₃O₁₂ thin films

The c-axis and a-axis preferential-oriented Bi_3.25Nd_0.75Ti₃O₁₂ (BNT) thin films together with (117)-orientation were deposited on (111)Pt/Ti/SiO₂/Si substrates by a metalorganic decomposition (MOD) method. The results show that the crystallinity of BNT thin films mainly depends on the pre-annealing conditions. BNT thin films with a-axis preferential orientation show high remnant polarization, high coercive field, high dielectric constant, high dissipation factor, and large capacitance tuning, while those with c-axis preferential orientation are on the contrary. The anisotropic ferroelectric properties of BNT thin films are similar to those of Bi₄Ti₃O₁₂ (BIT).