cial production, they are potential candidates for creating servo patterns that
will bring about enormous increase in the throughput of servo writing. Servo
patterns for an entire disk can be done in one shot and there is no need for
servo writing on a rotating disk which is prone to vibration. Nevertheless, all
these competing technologies have to show their capability of producing qual-
ity disks with desired features of given speci fi cations to generate quality signal
at competitive cost. Besides, it must be possible to scale the feature size so
that future areal densities are supported by these techniques.