Low-temperature oriented growth in [CoPt/MgO]_n multi-layer

Oriented-crystal growth of CoPt and MgO layers in the [CoPt/MgO]_n stacked structures at low-temperatures (< 650 °C) was investigated. For the CoPt (thickness: 40 nm)/MgO (50 nm) structures formed on Si(100) substrates, X-ray diffraction measurements revealed formation of poly-CoPt with random orientations and amorphous MgO. On the other hand, CoPt(111) and MgO(111) layers were dominantly obtained for the [CoPt (4 nm)/MgO (5 nm)]₁₀/Si(100) and [CoPt (2 nm)/MgO (2.5 nm)]₂₀/Si(100) structures. The (111) oriented growth of CoPt layers was found to be due to the template effect of MgO layers, which were crystallized to the (111) orientation if the layers were thin (< 5 nm).