Self-patterning of thin films using photosensitive sol-gel solution has advantages such as simple manufacturing process compared to photoresist/dry etching process. In this study, ferroelectric Sr0.9Bi2.1Ta2O9 thin films have been prepared by spin coating method using photosensitive sol-gel solution. Strontium ethoxide, tetramethylheptanedionato bismuth and tantalum ethoxide were used as starting materials. As UV exposure time to the SBT thin film increases, the intensity of UV absorption peak of metal beta-diketonate decreases due to degradation of solubility resulted from Metal-Oxygen-Metal (M-O-M) bond formation. The solubility difference by UV irradiation on SBT thin film allows to obtain a fine patterning of thin film. The ferroelectric properties of the UV irradiated SBT thin films are superior to those of the non-UV irradiated film. (C) 2003 Kluwer Academic Publishers.