Influence of annealing process on BiFeO_3 films by liquid phase self-assembled method

OTS as stencil,BiFeO3 films were successfully prepared on ITO/glass substrates by liquid phase self-assembled method using Bi(NO3)3·5H2O,Fe(NO3)3·9H2O and citrate acid as raw materials.The influence of annealing temperature and holding time on BiFeO3 films were studied.The crystalline behavior of BiFeO3 precursor particles were characterized by DSC/TG,the phase and surface morphology of BiFeO3 films prepared under different annealing process were characterized by XRD and FE-SEM.The results indicated that:the crystalline transition temperature of crystalline BiFeO3 films are around 440℃;the pure phase BiFeO3 films are actually obtained after annealing at 550℃ for two hours,the surface of the films are smooth and dense,the grains are completely developed and well-distributed,no obvious defect could be seen;grains would grow abnormally and impurity phase would forms when the annealing temperature is too high;BiFeO3 would pyrolyses when the holding time was too long.