Formation and scanning electron microscopy investigation of LiNbO3 films on silicon substrates

Abstract

The process of the production of LiNbO₃ thin films by sputtering onto cold silicon substrates followed by heat treatment was investigated. Composition, structure and physical properties of the films were investigated using light refractive indices, θ ?2θ X-ray diffraction and scanning electron microscopy, capacitance and dielectric constant measurements. The amount of the crystalline phase of the stoichiometric composition was found to be about 90%. The refractive index (λ = 632.8 nm) and the dielectric constant of the best samples were as high as 2.28 and 40, respectively. Insulating properties of this film structure were studied by SEM using e-beam sample charging. The potential images of the film structure provided evidence that current leakage takes place in the boundary areas between the crystallite and noncrystallite phases.