Patent ID: 8323515

Claim:
A method for making a master disk for imprinting magnetic recording disks, the method comprising: forming on a substrate a first pattern of ridges having generally parallel sidewalls, said first pattern being selected from one of concentric rings about a center on the substrate and generally radially-directed lines about a center on the substrate, wherein the radially inner ends of said lines have the same equal angular spacing about said center as the radially outer ends of said lines; depositing material on the sidewalls of the ridges of the first pattern; removing the ridges of the first pattern to leave pairs of parallel strips of sidewall material; forming on a substrate a second pattern of ridges having generally parallel sidewalls, said second pattern being different from said first pattern, said second pattern being the pattern not selected for said first pattern; depositing material on the sidewalls of the ridges of the second pattern; and removing the ridges of the second pattern to leave pairs of parallel strips of sidewall material.