Challenges in Sr₂FeMoO_6−δ Thin Film Deposition

Abstract

This work reviews some fundamental issues that are relevant for the fabrication of stable‐phase strontium ferromolybdate thin films. The main challenges for strontium ferromolybdate thin film deposition arise from the sensitivity of the material's magnetic properties to point defect formation: i) Antisite defect formation and oxygen nonstoichiometry should be avoided by precise composition control during film manufacturing; ii) a highly ordered state of the correct phase and B‐site cation valence will be obtained only in a very narrow window of growth conditions; iii) to avoid additional antisite disorder with decreasing synthesis temperature, the effective temperature at the film surface should be increased by an energy flux to the growing film surface. Since thin film deposition is nonequilibrium in nature, the review starts with the consideration of equilibrium phase stability. Cation and oxygen stoichiometries are analyzed with regard to their effect on key magnetic properties. Film strain formed due to thermal and lattice mismatch is of great concern since it influences the choice of the substrate. Finally, thin film deposition techniques are valued for their benefits in strontium ferromolybdate thin film technology.

Strontium Ferromolybdate-Based Magnetic Tunnel Junctions

“…Ions with energies up to several hundred eV are impinging on the growing film surface [21], providing a layer-by-layer growth with h << λ and a widely conformal substrate coverage at low incident fluxes. A review of SFMO film deposition and post-processing is provided in [22].…”

“…Unfortunately, most of the reports on SFMO thin film deposition are devoted to films with a thickness of about 100 nm [22]. To the best of our knowledge, there is only one report considering the thickness dependence of the saturation magnetization M s of SFMO thin films deposited by PLD onto STO (001) and (LaAlO 3 ) 0.3 (Sr 2 AlTaO 6 ) 0.7 (001) (LSAT) substrates [76].…”

Magnetization of Magnetically Inhomogeneous Sr2FeMoO6-δ Nanoparticles

“…However, wide application of SFMO is still missing, because of the low reproducibility of its magnetic properties originating in ceramic processing issues and its ageing upon contact with air and moisture. SFMO is a material which properties are very sensitive to disordering at the B-site, i.e., Fe Mo and Mo Fe antisite defect formation, nonstoichiometry of the magnetic Fe ions, and, with a lesser extent, to oxygen-and Sr-deficit [2].…”

Advanced Magnetic Oxides

“…And so we formulated the topic of IWAMO.The program of our workshop comprised a total of 13 keynote talks, 25 oral and 13 poster presentations. The presenters came from 16 countries.The following nine papers based on workshop presentations have been selected for publication in a dedicated issue of physica status solidi (b):The Feature Article by Gunnar Suchaneck et al [3] reviews some fundamental issues which are relevant for the fabrication of stable phase SFMO thin films with precise composition and adjusted oxygen content which possess high values of B-site ordering, Curie temperature, saturated magnetization and low-field magnetoresistance. Thin-film deposition techniques are valued for their benefits in SFMO technology.Artem Korshunov et al [4] present an experimental study of long-range magnetic order formation mechanisms in a layered Na 2 Ni 2 TeO 6 structure with a honeycomb arrangement of the magnetic atoms.…”

“…The Feature Article by Gunnar Suchaneck et al reviews some fundamental issues which are relevant for the fabrication of stable phase SFMO thin films with precise composition and adjusted oxygen content which possess high values of B‐site ordering, Curie temperature, saturated magnetization and low‐field magnetoresistance. Thin‐film deposition techniques are valued for their benefits in SFMO technology.…”