13:30 〜 15:30
▲ [14p-PA1-48] L10-MnAl thin film with high perpendicular magnetic anisotropy grown on L10-PtMn seed layer
キーワード：spintronics, high perpendicular magnetic anisotropy
Spin-orbit torque (SOT) induced magnetization switching in high spin Hall angle (SHA) material / ferromagnet (FM) heterostructures has been devoted lots of research attention as it shows promise for future ultrafast and power conservation magnetic memories (1). For FM layers, magnetic thin films with high perpendicular magnetic anisotropy (PMA) are needed for a prolonged data retention, which promote research of Mn-based alloys, such as L10-MnAl with high PMA (2). Comparing to those heavy metals with high SHA such as Pt, W, Ta, etc., Mn-based L10 and L21 type antiferromagets (AFM) XMnY (X=Ir, Pt, etc., Y=1, 3) are of significant interest not only due to their simple structure as well as the possibility of depositing Mn-based alloys with high PMA epitaxially on them (3), but also their possess high SHA (4-6). Although both L10-MnAl and L10-PtMn show application prospects for memory devices, experimental reports about epitaxial growth of MnAl on PtMn are absent. In this work, we report the crystal and magnetic properties of L10-MnAl thin films deposited on L10-PtMn seed layer.
All the samples were prepared by magnetron sputtering system. The stacking structures were MgO(001) sub. / PtMn (15) / MnAl (3-40) / Ta (3) in nm. We tuned substrate temperature (Ts), post annealing temperature (Ta), post annealing time to improve the L10 crystal orientation of both MnAl and PtMn.
Fig. 1 shows the thickness dependence of magnetic properties of prepared MnAl films. Although PMA magnitude Ku decreased rapidly with decreasing MnAl thickness, we have still measured a relative high Ku around 3 Merg/cc in a 3nm MnAl film. The decreased Ku with decreasing thickness is regarded as insufficient L10 structure of MnAl in thin film region since saturation magnetization Ms also decreased. This work was supported in part by GP-spin program.
All the samples were prepared by magnetron sputtering system. The stacking structures were MgO(001) sub. / PtMn (15) / MnAl (3-40) / Ta (3) in nm. We tuned substrate temperature (Ts), post annealing temperature (Ta), post annealing time to improve the L10 crystal orientation of both MnAl and PtMn.
Fig. 1 shows the thickness dependence of magnetic properties of prepared MnAl films. Although PMA magnitude Ku decreased rapidly with decreasing MnAl thickness, we have still measured a relative high Ku around 3 Merg/cc in a 3nm MnAl film. The decreased Ku with decreasing thickness is regarded as insufficient L10 structure of MnAl in thin film region since saturation magnetization Ms also decreased. This work was supported in part by GP-spin program.