Methods to determine gross and fine positioning on a reference surface of a media

A method to determine a position of a head on a reference surface of a media including at least one servo wedge extending radially across at least a portion of said reference surface, said servo wedge including a plurality of pulses and a plurality of chevrons, at least one of the pulses having a gap such that the at least one of the pulses is radially discontinuous, the method comprising:

• detecting the plurality of pulses with the head;
• moving the head across said reference surface in a first direction;
• detecting the gap;
• moving the head across said reference surface in a second direction opposite the first direction;
• detecting at least one edge of the gap;
• and
• determining a gross position based on the at least one edge.

A method to determine a position of a head on a reference surface of a media including a template pattern printed on said reference surface, said template pattern having at least one servo wedge extending radially across a portion of said reference surface, said servo wedge including a plurality of pulses and a plurality of chevrons, at least one of the pulses having a gap such that the at least one of the pulses is radially discontinuous, the method comprising:

• detecting the plurality of pulses with the head;
• moving the head across said reference surface in a first direction;
• detecting an absence of the at least one of the pulses;
• moving the head across said reference surface in a second direction opposite the first direction;
• detecting a radial transition from a presence of the at least one of the pulses to the absence of the at least one of the pulses;
• and
• determining a gross position based on the radial transition;
• measuring a phase of at least one of the chevrons measured at substantially the same radial location as the radial transition;
• determining a fine position based on the phase.

A method to manufacture a reference surface for self-servo writing one or more surfaces of one or more rotatable media in a data storage device, comprising:

• selecting a transfer medium having a template pattern, the template pattern including:
• a marker-zone to determine a position of a head on the reference surface, the marker-zone including one or more edges defined by a radial transition from a presence of a transition-pair to an absence of the transition-pair;
• wherein at least one of the one or more edges is located at a radial position;
• and
• wherein the at least one of the one or more edges precedes one or more chevrons located at the radial position;
• selecting a master disk having one or more surfaces;
• transferring the template pattern to one of the one or more surfaces of the master disk.

A method to manufacture a template pattern, comprising:

• forming a marker-zone to determine a position of a head in a data storage device, the marker-zone including one or more edges defined by a radial transition from a presence of a transition-pair to an absence of the transition-pair;
• wherein at least one of the one or more edges is located at a radial position;
• and
• wherein the at least one of the one or more edges precedes one or more chevrons located at the radial position.