Servo Signal Quality for Perpendicular Recording in Servo Write Process

In regards to servo-writing with perpendicular recording, we investigated servo-write quality and servo performance, and found that the premagnetization conditions, the magnetic-flux flow mechanism, and head structure strongly affect the servo-write quality. In response to these findings, we clarified that the flux flows through the writer to the reader are one of the root causes of servo-signal deterioration. In addition, we found that the flux amount is related to the magnetization switching ratio (MSR) - a one sided magnetization pole per writer-pole area. On the other hand, the reader can absorb flux even if it is far from the flux source. This means that not only the reader element but also the adjacent structure can absorb flux from the flux source.