We studied the effects of metal/MgO seeds (metal Ta, Ru, or Pd) on the crystalline structure and perpendicular magnetic properties of Co/Pd multilayers to investigate the possibility of developing a (100) texture with sufficiently high perpendicular anisotropy and small switching field distributions for applications such as patterned media and perpendicular magnetic random access memories. The Pd/MgO or the MgO seed successfully promoted a (100) texture of Co/Pd multilayers. In particular, the Pd/MgO seed developed a strong (100) texture in the Co/Pd multilayer and resulted in perpendicular magnetic anisotropies ∼2 × 106 erg/cm3. On the other hand, the Co/Pd multilayer with the Ta/MgO or the Ru/MgO seed showed a strong (111) texture, inducing a perpendicular magnetic anisotropy higher than that of the (100) textured films. The coercive fields of Co/Pd multilayers with the (111) texture were over 4 kOe and higher than those with the (100) texture, which were ∼2 kOe when they were patterned into 2 × 2 μm 2 islands. The switching field distributions of the Co/Pd multilayers with the (100) texture were smaller than those of the Co/Pd multilayers with the (111) texture. Our findings suggest that the Pd/MgO or the MgO seed can be a template suitable for device applications.
Bibliographical noteFunding Information:
This research was supported in part by Basic Science Research Program (2010-0015924), Pioneer Research Center Program (2009-008-1530), and Grant from the Center for Nanoscale Mechatronics & Manufacturing (2010K000189) funded by the Ministry of Education, Science and Technology, Korea and the IT R&D program of MKE/KEIT (KI002189, Technology Development of 30 nm Level High Density Perpendicular STT-MRAM).
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)