Solution Synthesis of <scp> <scp>BiFeO</scp> </scp> ₃ Thin Films onto Silicon Substrates with Ferroelectric, Magnetic, and Optical Functionalities

Abstract

Single‐ BiFeO 3 perovskite films onto Pt ‐coated silicon substrates have been fabricated by chemical solution deposition using a synthesis strategy based on the use of nonhazardous reagents. Different routes were tested to obtain precursors for the deposition of the films, inferring that bismuth ( III ) nitrate and iron ( III ) 2,4‐pentanedionate dissolved in acetic acid and 1,3‐propendiol led to the best solution. Ferroelectric, magnetic, and optical functionalities were demonstrated in these films, obtaining a high ferroelectric polarization at room temperature, ~67 μC × cm −2 , a dependence of the magnetization with the film thickness, 0.60 and 2.50 emu × g −1 for the ~215 and ~42‐nm‐thick films, and a direct band gap in the visible range, E g ~2.82 eV. These results support the interest of solution methods for the fabrication of BiFeO 3 thin films onto the silicon substrates required in microelectronic devices.