Ferroelectric properties of neodymium-doped Sr2Bi4Ti5O18 thin film prepared by solgel route

Sr2Bi4Ti5O18 (SBTi) and Nd-modified SBTi (SBNT) thin films were deposited on Pt/Ti/SiO2/Si (1 0 0) substrates using a sol-gel method. Structure, morphology and electric properties were investigated systematically. These films were randomly oriented and composed of rod-like grains. The remanent polarization (2Pr) and coercive field (Ec) of SBNT films were 30 μC/cm2 and 55 kV/cm, respectively. This value of 2Pr was much higher than the reported value of SBTi prepared by pulsed-laser deposition. More importantly, the SBNT films showed high fatigue resistance against continuous switching up to 3×109 cycles and excellent charge-retaining ability up to 3×104 s.