Low temperature synthesis and properties of lithium niobate thin films

Thin films of lithium niobate were deposited on silicon (100) by a sol‐gel technique and were annealed in oxygen at 400 °C. The annealed films were characterized by x‐ray diffraction and transmission electron microscopy which showed crystallization to LiNbO3, a preferred orientation of the films, and an average grain size of about 0.5 μm. Electrical characterization of the films in the metal‐ferroelectric‐semiconductor configuration showed evidence for ferroelectricity via the hysteresis loop. The dielectric constant and dissipation factor were measured at frequencies from 10 Hz to 10 MHz with a dielectric constant of 35 and dissipation factor of 0.004 at 100 kHz. The current‐voltage characteristics of the films exhibited asymmetric behavior, indicating a possible Schottky barrier and showed a leakage current density of 1.1×10−4 A/cm2 at 3 V.