Low-temperature crystallization induced by excimer laser irradiation of SrBi2Ta2O9 films

Transition of a SrBi2Ta2O9 precursor film from amorphous to crystalline was induced by excimer laser irradiation. Both fluorite and perovskite crystal line structures in such films were obtained by excimer laser irradiation at substrate temperatures between 200 and 500 degreesC, Either an addition of excess bismuth in the precursor film or an increase in the substrate tempe rature enhanced the formation of the perovskite structure in the excimer la ser-induced annealing process, resulting in the perovskite crystalline phas e at a relatively lower temperature of 500 degreesC, Such a low temperature is preferred when SrBi2Ta2O9 is used in ferroelectric devices. The mechani sm involved in this laser-induced crystallization is also discussed.