Nanoscale bit-patterned media for next generation magnetic data storage applications

Abstract

Design considerations and fabrication of bit-patterned magnetic recording media are presented. The application of ion-beam proximity printing, a high-throughput direct-write lithography, to media patterning is evaluated. Ultra-high magnetic anisotropy (Co/Pd)N magnetic multilayers are analyzed as candidates for patterned recording layers. Following patterning, optimized multilayers are shown to exhibit coercivity values well in excess of 14kOe. It is found that the magnetization reversal in patterned bits takes place via domain wall nucleation and propagation. The nucleation field and the location of the nucleation site strongly depend on the bit edge imperfections and contribute to finite switching field distribution. Playback off a bit-patterned media using various magnetic reader designs is analyzed using reciprocity theory.