Exchange Bias Effect along Vertical Interfaces in La0.7Sr0.3MnO3:NiO Vertically Aligned Nanocomposite Thin Films Integrated on Silicon Substrates

Abstract

Silicon (Si) integration is a critical step toward future applications of multifunctional oxides as nanoscale electronics and spintronic devices, because of the low cost and scalability of silicon substrates. As a demonstration, self-assembled (La0.7Sr0.3MnO3)x: NiO1–x (LSMO:NiO) vertically aligned nanocomposite (VAN) thin films with exchange bias (EB) properties have been successfully deposited on buffered Si substrates. To enable the epitaxial growth of LSMO:NiO VAN, SrRuO3/TiN was first grown as the buffer layers on Si substrates. The composition of the two-phases has been varied with x = 0.25, 0.5, 0.75, and 1 to explore the electrical transport and magnetic properties of the VAN system on Si. The irreversible temperature Tirr was found to increase with increasing NiO composition, with the highest for (LSMO)0.25(NiO)0.75 of ∼275 K, when the field was applied in the out-of-plane direction. In addition, the EB effect has been observed for all the nanocomposite films, with the highest HEB value of 300 Oe...