Formation of BiFeO3(110) films on ferromagnetic CoPt(111) electrode layer on glass substrates at reduced temperatures

Structure, ferroelectric, and magnetic properties of BiFeO3 (110) films grown on 20-nm-thick ferromagnetic CoPt(111) buffered glass substrate at 350–550 °C have been studied. (110)-texture of BFO films is developed at the reduced temperature as low as 400–550 °C, but isotropic orientation is found at higher temperature of 600 °C. Low temperature deposition results in dense microstructure, fine grains, and smooth surface morphology, which are favorable for applications. BFO(110) films on CoPt(111) underlayer exhibit desired ferroelectric and magnetic properties. Electrical polarization (2Pr) of 96–137 μC/cm2 and coercive field (Ec) of 495–618 kV/cm for studied BFO (110) films are comparable to those grown on single crystal substrates. Moreover, exchange bias between BFO and CoPt is observed after a field cooling from 370 °C to room temperature (RT) at 2 kOe. Large exchange bias field of 155 Oe at RT and coercivity of 1631 Oe are obtained. The presented results provide useful information for the applications based on electric-magnetic interactions.