Crystallization behavior of Nd-doped SrBi2Ta2O9 thin films prepared by magnetron sputtering

Nd-doped SrBi2Ta2O9 thin films are magnetron-sputtered on Pt/Ta/SiO2/Si substrates. The effect of heating rate on crystallization behavior is investigated with conventional furnace annealing (CFA) and rapid thermal annealing (RTA). Grazing incidence X-ray diffraction and field emission scanning electron microscopy reveal that the crystallization goes through three stages (phases): amorphous, fluorite and finally Aurivillius. Under RTA, the fluorite-to-Aurivillius transformation starts around 100 °C lower than that under CFA. The reasons behind the transformation temperature drop are also discussed.