We fabricated Co-Pt magnetic dot arrays using an electron beam writing and a low-energy ion etching in order to prevent from the deterioration of the magnetic properties. By comparing the results of X-ray magnetic circular dichroism measurement and micro magnetic simulation, it was found that the etching using low-energy ions cause little damage on not only the magnetization but also the anisotropy field. These results demonstrate the effectiveness of the etching using low-energy ions for realization of bit-patterned media with an areal density of 1 Tbit/in^2. Furthermore, the magnetic isolation between the dots in the magnetic dot array with the dot pitch of 30 nm was confirmed by SEM and MFM observations.
