Annealing effect on perpendicular [CoFe /Pd]n multilayers

Perpendicular magnetic anisotropy is investigated in [CoFe/Pd]n multilayers grown on Si/SiO2 substrates. Coercivity is measured for [CoFe(t1)/Pd(t2)]n multilayers with t1 = 0.4 or 0.5 nm when t2 varies from 0.4 to 2.7 nm. Furthermore, there is an enhancement of the perpendicular anisotropy on increasing the thickness of the Pd layer and the annealing temperature. We also compare the [CoFe/Pd]n multilayers to those made with a thin CoFeB layer in contact with Pd inserted at the top or bottom of the [CoFe/Pd]n stacks. The perpendicular magnetic anisotropy is maintained.