Method of manufacturing a dual-sided stamper/imprinter, method of simultaneously forming magnetic transition patterns and dual-sided stamper/imprinter

A method of simultaneously forming magnetic transition patterns in a plurality of spaced-apart layers of magnetic material by means of contact printing, comprising steps of:

• (a) providing a dual-sided stamper/imprinter having a first topographically patterned imprinting surface comprising a plurality of projections and depressions arranged in a pattern corresponding to a first magnetic transition pattern to be formed in a first one of said plurality of spaced-apart layers of magnetic material and an oppositely facing second topographically patterned imprinting surface comprising a plurality of projections and depressions arranged in a pattern corresponding to a second magnetic transition pattern to be formed in a second one of said plurality of spaced-apart layers of magnetic material, at least said first and second imprinting surfaces of said stamper/imprinter comprised of at least one magnetic material having high saturation magnetization Bsat≧about 0.5 Tesla, and high permeability μ≧about 5, selected from the group consisting of Ni, NiV, NiFe, CoNiFe, CoSiFe, CoFe, and CoFeV;
• (b) providing a first workpiece including a first surface comprised of said first layer of magnetic material, said first layer of magnetic material including a plurality of unidirectionally magnetically aligned magnetic domains extending to said first surface with an initial direction of alignment;
• (c) providing a second workpiece including a second surface comprised of said second layer of magnetic material, said second layer of magnetic material including a plurality of unidirectionally magnetically aligned magnetic domains extending to said second surface with an initial direction of alignment;
• (d) contacting said first surface of said first workpiece with said first topographically patterned imprinting surface of said dual-sided stamper/imprinter;
• (e) contacting said second surface of said second workpiece with said second topographically patterned imprinting surface of said dual-sided stamper/imprinter;
• (f) simultaneously selectively re-aligning the direction of alignment of the magnetic domains of those portions of said first and second layers of magnetic material in contact with said projections or facing said depressions of said first and second topographically patterned imprinting surfaces, respectively, such that said magnetic domains of said contacted portions or said facing portions are aligned in a direction reverse that of said initial direction, wherein the combination of aligned+re-aligned magnetic domains of each of said first and second layers of magnetic material form first and second magnetic transition patterns replicating the patterns of projections and depressions of said first and second topographically patterned imprinting surfaces, respectively;
• and
• (g) removing said first and second workpieces from contact with said dual-sided stamper/imprinter.