Perpendicular magnetic properties of sputtered Pt/Co2MnSi/MgO nanostructures

Co2MnSi (CMS) alloy is one of promising ferromagnetic electrode materials for spintronics devices. A series of CMS films sandwiched by Pt and MgO are sputtered. For the as-deposited films with in-plane anisotropy a low saturation magnetization of 494.8 +/- 30.0 emu/cm3 is determined. After annealing perpendicular magnetic anisotropy (PMA) is shown to build in the stacks with CMS thickness ranged from 2 to 3 nm. The largest saturation magnetization of 1002.0 +/- 68.5 emu/cm3 is obtained. CMS/MgO interface is found to be requisite for PMA development and Pt/CMS interface is shown to be not essential for PMA. Thermal stability is shown to be significantly improved with the insertion of Pt buffer. Strong PMA over 1 x 106 erg/cm3 is demonstrated in a wide annealing temperature range with the insertion of 0.8 nm MgO and 4 nm Pt buffer. Our results provide some useful information for designing next generation CMS-based spintronic devices.

Automated summary

Co2MnSi (CMS) alloy is a promising ferromagnetic electrode material for spintronics devices. By annealing the CMS films, perpendicular magnetic anisotropy (PMA) can be introduced, leading to an increase in the saturation magnetization. The CMS/MgO interface is found to be crucial for PMA development, while the Pt/CMS interface is not essential.