Enhanced magnetic properties of chemical solution deposited BiFeO3 thin film with ZnO buffer layer

Magnetic properties of BiFeO3 films deposited on Si substrates with and without ZnO buffer layer have been studied in this work. We adopted the chemical solution deposition method for the deposition of BiFeO3 as well as ZnO films. The x-ray diffraction measurements on the deposited films confirm the formation of crystalline phase of BiFeO3 and ZnO films, while our electron microscopy measurements help to understand the morphology of few micrometers thick films. It is found that the deposited ZnO film exhibit a hexagonal particulate surface morphology, whereas BiFeO3 film fully covers the ZnO surface. Our magnetic measurements reveal that the magnetization of BiFeO3 has increased by more than ten times in BiFeO3/ZnO/Si film compared to BiFeO3/Si film, indicating the major role played by ZnO buffer layer in enhancing the magnetic properties of BiFeO3, a technologically important multiferroic material.

► Enhanced magnetization of BiFeO3 is important for strong magnetoelectric coupling. ► BiFeO3 film with ZnO buffer layer was successfully synthesized by chemical method. ► Magnetization of BiFeO3 has increased by more than 10 times with ZnO buffer layer. ► A mechanism for enhancement in ferromagnetism of BiFeO3 film is proposed.