Epitaxial ferromagnetic oxide thin films on silicon with atomically sharp interfaces

摘要

A bottleneck in the integration of functional oxides with silicon, either directly grown or using a buffer, is the usual formation of an amorphous interfacial layer. Here, we demonstrate that ferromagnetic CoFe_2O_4 films can be grown epitaxially on Si(111) using a Y_2O_3 buffer layer, and remarkably the Y_2O_3/Si(111) interface is stable and remains atomically sharp. CoFe_2O_4 films present high crystal quality and high saturation magnetization.