Study of Lithographically Defined Data Track and Servo Patterns

Abstract

We report on fabrication of discrete tracks on perpendicular magnetic recording (PMR) media with an e-beam lithographical process. We studied the recording performance of the e-beam media on a spinstand in parallel with conventional PMR media. Discrete track media show significant reduction in adjacent track erasure (ATE). We studied and quantitatively measured the source of the ATE improvement, and developed a triple track geometrical model to calculate achievable track density for both discrete track recording (DTR) and continuous media. From the model, we identify two factors of DTR that contribute to reaching a higher TPI. Using the same fabrication technique, we also studied servo burst design and its playback waveform quality. At 250 ktpi, we compare DTR servo bursts with servo bursts written with a conventional method. DTR servo bursts show better edge definition, which can translate to better position error signal sensitivity and support higher TPI in the future.Discrete tracks are fabricated on conventional PMR media with an e-beam litho graphical process. The recording performance is studied on a spinstand in parallel with conventional PMR media. Discrete track media shows significant reduction in adjacent track erasure (ATE). The source of the ATE improvement is studied and quantitatively measured. A triple track geometrical model is developed to calculate achievable track density for both DTR and continuous media. From the model, we identify two factors of DTR, which contribute to reaching a higher TPI. Using the same fabrication technique, we also study servo burst design and its playback waveform quality. At 250 ktpi, we compare DTR servo bursts and servo bursts written with a conventional method. DTR servo bursts show better edge definition, which can translate to better PES signal sensitivity and support higher TPI in the future.