A Pd/Si dual seedlayer consisting of a 5-nm-thick Pd layer on a 5-nm-thick Si layer was deposited on a substrate prior to the formation of a [Co/Pd]n multilayered perpendicular magnetic recording medium, and the effect of the deposition conditions of the dual seedlayer on the magnetic properties of the [Co/Pd]n, multilayered film was investigated. The addition of N
2 to the sputtering Ar gas during the Pd upper seedlayer deposition was effective for decreasing the value of α, which is the slope of a perpendicular
M-H loop, defined as 4π(
dM/
dH)
H=Hc, and reflects the magnitude of intergranular exchange coupling The value of α was further decreased by post-annealing of the Pd/Si dual seedlayer. By combining the effects of N
2 addition and the post-annealing in preparing the Pd/Si dual seedlayer, both an increase in the reproducing resolution (D
50) and a reduction in the medium noise were achieved. Furthermore, the preparation conditions were found to influence the surface morphology and the state of chemical bonding of the Pd/Si dual seedlayer.
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