Si integration of La0.7Sr0.3MnO3:BiFeO3 nanocomposite thin films with strong exchange bias coupling

Abstract

Integrating functional oxide-based nanocomposite thin films on Si wafer is a large step toward their applications in electronics and spintronics. Here, to overcome the large lattice mismatch and potential inter-diffusion between the complex oxides and Si, a set of buffer layers of SrRuO3 (SRO)/TiN have been applied. The La0.7Sr0.3MnO3:BiFeO3 system has been selected to grow on the SRO/TiN buffered Si, and the nanocomposite films exhibit highly textured growth along the c direction for both phases. The microstructure study shows a typical vertically aligned nanocomposite structure of the films, which is similar to the same films on single crystal oxide substrates. Furthermore, magnetic measurements indicate the strong ferromagnetic–antiferromagnetic coupling in the nanocomposite system, which refers to the large exchange bias value HEB of ∼1800 Oe in the L0.5B0.5 sample under out-of-plane magnetic field. This work provides an effective approach for the Si integration of oxide-based nanocomposite thin films.