S. Tanaka et al., CHARACTERIZATION OF MAGNETIZING PROCESS FOR PRE-EMBOSSED SERVO PATTERN OF PLASTIC HARD DISKS, IEEE transactions on magnetics, 30(6), 1994, pp. 4209-4211
Rigid disks which have pre-embossed servo patterns have been developed
. These media make it possible to follow tracks less than 5 mu m pitch
. The substrates are made hom plastic; and pre-embossed servo patterns
and discrete data tracks are made by a stamping technology similar to
optical disks. To generate signals from pre-embossed servo patterns,
the magnetization direction of the elevated pattern and recessed area
must be opposing. Therefore, a two-step magnetization method has been
developed. Based on experimental results, optimum conditions are met w
hen the magnetization transition occurs at the upper edge of the patte
rns.