engleski

Optimisation of BaTiO3 thin films prepared by magnetron sputtering for sensor and solar cell use

Perovskites are mineral materials which contain titanium, oxygen and at least one additional metal such as: Sr, Ba, Ca. Because of their good ferroelectric and piezoelectric properties, perovskites have found their use in electronics (capacitors, microphones, devices for digital data storage). Barium titanate (BaTiO3) is a ceramic perovskite oxide that besides having ferroelectric has good optical properties. That alone makes it an interesting material for photovoltaics. Recently BaTiO3 was used in thin film form (pure or as a composit material with TiO2) as a electrode in dye sensitized solar cells (DSSC). It was also shown that an addition of a BaTiO3 thin film can improve overall performance in gas sensors based on CuO. BaTiO3 can be prepared by chemical (hydrolysis, hydrothermal synthesis, sol-gel method) and physical methods (such as laser ablation, spray pyrolysis and magnetron sputtering). Magnetron sputtering is a widely used method for thin film preparation. The method is based on the process in which plasma is created and positively charged ions from the plasma are accelerated by an electrical field and strike the negative electrode with sufficient force to eject atoms from the target. Atoms ejected from the target are then depositioned on the substrate placed in proximity to the target, producing a thin film. Choosing different target materials there can be prepared various thin films, comprised of metals, oxydes, semiconductors or ceramics. In this paper, using RF magnetron sputtering, there were produced BaTiO3 thin films. Deposition parameters were optimised for producing thin films with the most favorable optical and electrical properties, keeping in mind the application for photovoltaic cells and sensors. Structural propertis of the obtained BaTiO3 thin films (examined by Raman spectroscopy, GIXRD and Scanning Electron Microscopy) were correlated to optical properties (examined by UV-VIS spectroscopy).

Barium titanate ; magnetron ; magnetron sputtering ; thin films ; sensors ; solar cell

nije evidentirano