Epitaxial growth and magnetic properties of Fe_3O_4 films on TiN buffered Si(001), Si(110), and Si(111) substrates

摘要

Epitaxial Fe_3O_4 thin films were grown on TiN buffered Si(001), Si(110), and Si(111) substrates by dc reactive sputtering deposition. Both Fe_3O_4 films and TiN buffer are fully epitaxial when grown at substrate temperatures above 150 ℃, with textured single phase Fe_3O_4 resulting from room temperature growth. The initial sputtered Fe_3O_4 formed nuclei islands and then coalesced to epitaxial columnar grains with increasing film thickness. The magnetization decreases and the coercive field increases with decreasing film thickness. There is no in-plane magnetic anisotropy of epitaxial Fe_3O_4(001) on Si(001) but Fe_3O_4 films grown on Si(110) and Si(111) substrates show uniaxial in-plane magnetic anisotropy.