Magnetic media patterning via contact printing utilizing stamper having magnetic pattern formed in non-magnetic substrate

Abstract

A stamper / imprinter for use in forming a magnetic transition pattern in a magnetic material by means of contact printing, comprising: (a) a non-magnetic substrate having a major surface comprising a patterned plurality of spaced-apart recesses with a plurality of non-recessed areas therebetween, the patterned plurality of recesses corresponding to the magnetic transition pattern to be formed in the magnetic material; and (b) unidirectionally permanently magnetized material filling each of the plurality of recesses and having exposed surfaces substantially coplanar with the plurality of non-recessed areas.

Description

CROSS-REFERENCE TO PROVISIONAL APPLICATION [0001] This application claims priority from U.S. provisional patent application Ser. No. 60 / 392,986 filed Jun. 28, 2002, the entire disclosure of which is incorporated herein by reference.FIELD OF THE INVENTION [0002] The present invention relates to methods and devices for forming magnetic transition patterns in a layer or body of magnetic material. The invention has particular utility in the formation of servo patterns in the surfaces of magnetic recording layers of magnetic data / information storage and retrieval media, e.g., hard disks. BACKGROUND OF THE INVENTION [0003] Magnetic recording media are widely used in various applications, e.g., in hard disk form, particularly in the computer industry for storage and retrieval of large amounts of data / information in magnetizable form. Such media are conventionally fabricated in thin film form and are generally classified as “longitudinal” or “perpendicular”, depending upon the orientation (...

AI Technical Summary

Benefits of technology

This approach simplifies the process, reduces defects, and enables high-quality, rapid replication of servo patterns in magnetic recording media, maintaining compatibility with automated hard disk manufacturing technology.

Problems solved by technology

Because of the locational precision needed, writing of servo patterns requires expensive servo-pattern writing equipment and is a time consuming process.

However, the above-described method incurs several drawbacks associated with its implementation in an industrially viable manner.

Specifically, a “one-of-a-kind” master writer with a very high write field gradient is necessary for writing the requisite high intensity, master magnetic servo pattern onto the master disk, and a complicated means for rotating the aligned master servo-writer disk and “slave” workpiece magnetic disk is required, as is a complex system for controlling / regulating / rotating the intensity (i.e., magnitude) and directions of the magnetic assist field.

In practice, however, the design and manufacture of stampers / imprinters for performing servo patterning of magnetic recording media by means of contact printing, as described supra, incur problems associated with defect control and the requirement for application of an external magnetic field during the printing process for effecting selective re-alignment of the magnetic domains to yield the desired magnetic transition pattern.

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