A magnetic medium for use in data recording that has a series of
concentric magnetic track portions separated from one another by
non-magnetic portions or gap portions. The magnetic portions define data
tracks and prevent signals from one track from bleeding into another
track. Because the data tracks are distinctly separated, adjacent track
interference is completely avoided. The disk may be manufactured by
depositing first and second materials sequentially onto a rotating tube,
the first and second materials having different etch rates. The tube may
then be slided into disks and the disks subjected to a reactive ion etch
(RIE) to form a disk surface having concentric raised portions separated
by concentric recessed portions. A magnetic material can then be
deposited. An optional chemical mechanical polishing process can then be
performed to planarize the surface, resulting in a planar surface having
rings of magnetic material separated by rings of non-magnetic material.