The four layer-structured Bi5FeTiO15(BFTO) thin films were deposited on a Pt/Ti/SiO2/Si substrates by a sol-gel method.The effects of precursor concentration and the heating rate during annealing on the crystallization were investigated.It was found that the precursor solution concentration of < 0.05 mol/L is not conducive to the formation of the four-layered perovskite structure films.The optimal preparation process to deposit the BFTO thin films occurred at the precursor concentration of 0.05 mol/L and an...