Magnetite thin films grown on different flexible polymer substrates at room temperature: Role of antiphase boundaries in electrical and magnetic properties

Abstract

Currently, there is an enormous need for flexible electronic devices given their astonishing competencies. In this view, we investigated the structural, electrical, and magnetic characterstics of magnetite (Fe3O4) thin films with a thickness of 100 nm prepared using a reactive RF sputtering technique at 300 K on polycarbonate (PC), polymethyl methacrylate (PMMA), and polythene terephthalate (PET) flexible substrates. The structural properties showed that the films grown on PC, PMMA, and PET substrates exhibited the pure form of Fe3O4 nanostructures by flowing oxygen with a flow rate of 3.5 sccm. The Verwey transition temperatures (Tv) of ∼123 K, ∼124 K, and ∼126 K; saturation magnetization (Ms) values of ∼220 emu/cm3, ∼235 emu/cm3, and ∼261 emu/cm3; and magnetoresistance (MR) values of −7.1%, −7.3%, and −7.8% under the H∥Film plane below 60 kOe at 300 K for 100-nm-thick Fe3O4 film on PC, PMMA, and PET substrates respectively were observed. These remarkable results were interpreted and the effect of antiferromagnetically (AFM) coupled antiphase boundaries (APBs) was explained, which suggested that Fe3O4/PET heterostructure can be a most promising component for flexible spintronics.