Solution Synthesis of BiFeO₃ Thin Films onto Silicon Substrates with Ferroelectric, Magnetic, and Optical Functionalities

Abstract

Single‐BiFeO3 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, Eg ~2.82 eV. These results support the interest of solution methods for the fabrication of BiFeO3 thin films onto the silicon substrates required in microelectronic devices.

Defect-mediated ferroelectric domain depinning of polycrystalline BiFeO3 multiferroic thin films

“…10 Ten layers of this solution were successively deposited and pyrolyzed before the whole stack was crystallized by rapid thermal annealing (RTA) at 773 K for 60 s in air. The resulting as-crystallized sample will be denoted as "fresh" BiFeO 3 film.…”

“…The use of a bismuth excess in the precursor solution 10 would compensate for the V Bi 000 generated by volatilization from the film, leaving the V O •• defect as the main candidate responsible for pinning. (2) Postannealing in oxygen, however, results in higher dielectric losses at zero DC bias.…”

Growth of BiFeO3thin films by chemical solution deposition: the role of electrodes

“…Acetic acid (C2H4O2 -AcOH, Merck, 100%) and 1,3 propanediol (C3H8O2, Aldrich, 98%) were used as solvents 25 .…”

Integration of functional complex oxide nanomaterials on silicon

“…In addition, bismuth ferrite BiFeO 3 (BFO) thin films have been successfully prepared onto silicon and Pt-coated silicon substrates at low temperatures (400 • C) using a synthesis strategy based on the use of purely water-based systems and nonhazardous reagents [42,43].…”