Structural, electrical, and magnetic properties of BiFeO3-Y3Fe5O12 bulk ceramics and sputtered thin films

Abstract The fabrication of composites consisting of ferromagnetic and ferroelectric complex oxides is important for the development of versatile multifunctional electronic devices. Herein, 0–3 type ceramic (BiFeO3)1-x-(Y3Fe5O12)x (0 ≤ x ≤ 0.3) composites, comprising Y3Fe5O12 particles randomly dispersed in a BiFeO3 matrix, were synthesized via a solid-state reaction. Two phases, BiFeO3 and Y3Fe5O12, were observed without the formation of any secondary phases. With increasing Y3Fe5O12 content in the composites, the leakage current dramatically decreased while the magnetic moment increased. A sputter deposition technique was introduced to grow BiFeO3-Y3Fe5O12 composite thin films on (0 0 1)-oriented SrTiO3 substrates. The BiFeO3-Y3Fe5O12 thin films grown at 650 °C exhibited isotropic magnetic behavior with low magnetization, whereas the magnetic hysteresis loops of the annealed films revealed two distinct slopes. The portion of the steeper slope near the zero field originated from the soft magnetic Y3Fe5O12 and increased with higher annealing temperature. This new fabrication of BiFeO3-Y3Fe5O12 composite thin films is promising to the design of new electronic devices with multifunctional properties.