Synthesis and characterization of ferroelectric properties of Ce2Ti2O7 thin films with Ce3+ by chemical solution deposition

Ferroelectric Ce2Ti2O7 films were grown with a pseudo-pyrochlore structure on an Y2O3/Si substrate by low-vacuum (6.664 Pa) anneal at 800 °C using chemical solution deposition. Trivalent state of Ce could be confirmed by using X-ray absorption-near-edge-structure. The dielectric constant at 1 MHz and dielectric loss of the film in the Pt/Ce2Ti2O7/Pt structure were measured as 48.7 and 0.013, respectively. A relatively large memory window of 1.24 V was measured with a Pt/Ce2Ti2O7/Y2O3/Si capacitor structure at an applied voltage of 6 V. The capacitance–voltage hysteresis was symmetrical without shift from the origin due to an effective suppression of the interfacial SiO2 formation under low-vacuum annealing conditions. The Ce2Ti2O7 film was compatible for application to a ferroelectric gate.