Preparation and Ferroelectric Properties of Ho3+/Mo6+ Cosubstituted Bi4Ti3O12 Thin Films by Sol–Gel Method

We have prepared Ho3+/Mo6+ cosubstituted bismuth titanate [(Bi3.6Ho0.4)3.99- Ti2.985Mo0.015O12, BHTM] thin films on Pt/Ti/SiO2/Si substrates using the sol–gel method. The crystal structure and morphology of the BHTM films were characterized. The BHTM samples show a single phase of Bi-layered Aurivillius structure and a dense microstructure. The dielectric constant and dielectric loss of the BHTM films were about 359 and 0.043, respectively, at a frequency of 1 MHz. The films exhibit 2Pr of 57.7 μC/cm2 and 2Ec of 290.0 kV/cm at an applied field of 470 kV/cm, and have fatigue-free characteristics. They also showed good insulating behavior according to leakage current testing.