Coercive Force Enhanced by Nanometer-Sizing of Magnetic Column and Measured by X-Ray Magnetic Circular Dichroism (XMCD)

We have studied the possibility to form fine magnetic column arrays using 30-keV-electron beam (EB) drawing with thin calixarene resist and 200-eV-Ar ion milling, and nanometer-sizing effect of the magnetic column on the corecive force for patterned media. We achieved 20-nm-sized resist dot arrays on PtCo magnetic and thin metals layers on glass substrate. We formed fine magnetic column arrays with a diameter of 39 to 106 nm and a space of about 100 nm using the resist pattern by the 200-eV Ar ion-milling. Using the nano magnetic column arrays, the hysteresis were measured by X-ray magnetic circular dichroism (XMCD) with an energy of 11.57 keV, which corresponds to an energy edge of Pt-L3. It is clarified that a coercive force of the nanometer-sized magnetic column increased as the diameter decreased.