Abstract
A new method of fabricating patterned media was developed. Circumferential magnetic patterned media were prepared on 2.5-inch-diameter glass plates. A Ni master disk contraining spiral patterns with 60-250-nm-wide lands and a 400-nm-wide groove was pressed against a resist film on a CoPt or CoCrPt film to transfer the spiral patterns. A diblock copolymer solution was cast into the obtained grooves, and then annealed to prepare self-assembling dot structures aligned along the grooves. According to the dot patterns, lower magnetic films were patterned by ion milling to yield patterned media with a 40-nm diameter. The coercive forces and squareness ratios of the patterned media were greater than those of continuous media. Single magnetic domains with an almost perpendicular orientation were confirmed in each magnetic dot.
