Epitaxial NiMnSb thin films prepared by facing targets sputtering

Abstract

We have prepared high-quality epitaxial NiMnSb thin films by facing targets sputtering (FTS), using an MgO monocrystalline substrate with an Mo-buffer layer. The epitaxial growth relation has been found to be (1 0 0)NiMnSb∥(1 0 0)Mo∥(1 1 0)MgO. Optimum deposition conditions have been determined to achieve highly ordered, continuous films with low rms roughness. The magnetic and transport properties of these films are comparable to that of bulk single crystals and are found to be independent thickness in the range 100–1000 Å. The residual resistivity in particular ( ρ =5.3 μΩ cm for a 1000 Å films) is much lower than what has been reported so far in the literature. All these features should ensure a high degree of spin polarisation and a minimum spin-flip scattering in multilayered structures, thus enabling the use of these films for high-quality TMR/GMR devices fabrication.