Performance and Potential of High-Density Bit Recording Using Patterned Master Contact Duplication

摘要

We investigated both the read/write performance for sub-micron bits and the possibility of recording servo-patterns of over 300 Gbits/in{sup}2 by using patterned master contact duplication, which is expected to resolve the problems of conventional servo-track writing. The experimental value of the spacing loss factors for sub-micron bits resulting from the duplication was around 20 dB, which was lower than that for reported conventional magnetic head recording. The reason for the low value is that the duplication suffers less from recording demagnetization because a static recording method is used and the S{sup}* value of the slave is high. A reading experiment involving duplication using a master disk with a track width of 190 nm and a bit length of 123 nm yielded a signal-to-noise ratio of 17.9 dB, which was a little larger than that of magnetic head recording. The simulation of a magnetic field to duplicate a high-density servo-pattern indicated that the magnetic field was large enough to record servo-patterns of as much as 370 Gbits/in{sup}2. These studies demonstrated the potential of this method for high-density servo-pattern recording.