PREPARATION AND CHARACTERIZATION OF OPTICAL PROPERTIES OF BARIUM TITANATE NANOTHIN FILMS

Barium titanate thin films are key materials for use in the solid-state devices, including capacitors, memories, thermistors, sensors, actuators and so on. High transmittance barium titanate thin films are suitable candidate for various electro-optic applications such as dielectric mirrors. In this research high transmittance barium titanate nanothin films were prepared by sol - gel dip - coating method, then the optical properties of the prepared nanofilms was characterized. Experimental results indicate that the surface morphology of prepared nanothin films were improved and as a result of that, a better optical properties, less optical losses were obtained in contrast with other reported data. It was found that optical propagation loss of barium titanate nanothin film was much lower than normal polycrystalline barium titanate thin film. Results also indicate that Increment of the calcination temperature reduces the thin films transparency and thickness. Other results show that increment of withdrawal rate of the substrate from the prepared sol lead to increment of thin films thickness and decrease in thin films transparency. The prepared high transparent nanothin film was amourphous and was as thin as 30 nm. It seems to us that, prepared barium titanate nanothin films would be suitable for several optical and electro-optical applications.