Cailiao gongcheng (Feb 2020)
Effect of MgO/Pd underlayer on perpendicular magnetic anisotropy and thermal stability of CoSiB/Pd multilayers
Abstract
The CoSiB/Pd multilayers with MgO/Pd underlayer were deposited by magnetron sputtering technique on the glass substrate. The effect of MgO underlayer's thickness t on perpendicular magnetic anisotropy of CoSiB/Pd multilayer was studied, and the thermal stability of multilayers with MgO/Pd underlayer was analyzed. The results show that the performance of PMA of samples improves due to the introduction of the MgO in the bottom layer through the analysis of anomalous Hall effect of samples, when the thickness t of MgO is 3.5 nm, the squareness of the sample is the best. The hysteresis loops of the best sample MgO(3.5 nm)/Pd(3 nm)/[CoSiB(0.5 nm)/Pd(0.8 nm)]2/Ta(2 nm) is tested, and the effective magnetic anisotropy constant(Keff) of the sample reaches 2.0×105 J/m3. The thermal stability analysis shows that the Keff reaches the maximum value 2.6×105 J/m3 at the annealing temperature of 200℃; the sample can still maintain good PMA performance, when the annealing temperature reaches 400℃.