Perpendicular patterned magnetic media
View Patent ↗The invention is directed to patterned magnetic media for use in magnetic recording and data storage, and various conditioning techniques that can be used to magnetically condition the patterns. For example, a medium can be formed to exhibit a pattern of surface variations defined by patterned areas and non-patterned areas. Techniques are described for magnetically conditioning the patterned areas. The techniques may be useful for perpendicular patterned media, i.e., media having patterns formed on the media surface and having a magnetic anisotropy that is perpendicular to the plane of the medium. In particular, perpendicular magnetic anisotropy has been found to be an important factor that allows effective conditioning of patterned features having relatively small widths.
1. A magnetic recording medium comprising:
a substrate; and
a magnetic recording layer exhibiting perpendicular magnetic anisotropy formed over the substrate, the magnetic recording layer including a pattern of surface variations defined by patterned areas and non-patterned areas, wherein the patterned areas are magnetized differently than the non-patterned areas, wherein at least some of the patterned areas define a width of less than approximately 5.0 microns.
2. The magnetic recording medium of claim 1 , wherein at least some of the patterned areas define a width of less than approximately 1.0 micron.
3. The magnetic recording medium of claim 1 , wherein the patterned areas comprise bumps.
4. The magnetic recording medium of claim 3 , wherein the non-patterned areas comprise regions between the bumps.
5. The magnetic recording medium of claim 1 , wherein the patterned areas are magnetized with a polarity that is opposite a polarity of the non-patterned areas.
6. The magnetic recording medium of claim 1 , wherein the magnetic recording layer is a substantially continuous magnetic recording layer formed over the substrate.
7. A magnetic recording medium comprising:
a substrate; and
a magnetic recording layer exhibiting perpendicular magnetic anisotropy formed over the substrate, the magnetic recording layer including a pattern of surface variations defined by patterned areas and non-patterned areas, wherein the patterned areas are magnetized differently than the non-patterned areas, wherein the patterned areas comprise features selected from the group consisting of: bumps, pits, ridges, rails, channels, and grooves.
8. The magnetic recording medium of claim 1 , further comprising a layer formed between the substrate and the magnetic recording layer.
9. The magnetic recording medium of claim 8 , wherein the layer formed between the substrate and the magnetic recording layer defines the pattern of surface variations, and wherein the magnetic recording layer substantially conforms to the pattern of surface variations.
10. The magnetic recording medium of claim 1 , wherein the magnetic recording layer includes a number of sub-layers.
11. The magnetic recording medium of claim 1 , wherein the patterned areas define servo patterns for the medium.
12. The magnetic recording medium of claim 1 , wherein the patterned areas define stored information.
13. The magnetic recording medium of claim 1 , wherein the patterned areas are all magnetized substantially the same.
14. A magnetic recording medium comprising:
a substrate; and
a magnetic recording layer exhibiting perpendicular magnetic anisotropy formed over the substrate, the magnetic recording layer including a pattern of surface variation defined by patterned areas and non-patterned areas, wherein the patterned areas are magnetized differently than the non-patterned areas, wherein the patterned areas are all magnetized substantially the same and the non-patterned areas are randomly magnetized.
15. A magnetic recording medium comprising:
a substrate; and
a substantially continuous magnetic recording layer exhibiting perpendicular magnetic anisotropy formed over the substrate, the magnetic recording layer having a pattern of surface variations defined by patterned areas and non-patterned areas, wherein the patterned areas are magnetized with a polarity that is opposite a polarity of the non-patterned areas, and wherein at least some of the patterned areas define a width less than approximately 5.0 microns.
16. The magnetic recording medium of claim 15 , wherein the patterned areas are all magnetized substantially the same and the non-patterned areas are all magnetized substantially the same.
17. A perpendicular magnetic recording medium comprising a pattern of surface variations defined by patterned areas and non-patterned areas, the patterned areas being magnetized differently than the non-patterned areas, wherein the patterned areas are magnetized with a first polarity, and the non-patterned areas are magnetized with a second polarity, the second polarity being opposite the first polarity.