High coercivity magnetic recording medium comprising a sputter textured layer
AssigneeSeagate Technology LLC
InventorsXing Song, Ga-Lane Chen, Charles Leu, Qixu Chen
Life of this patent
Estimating the term…
Abstract
Reproducible texturing of magnetic recording media is enhanced by sputtering a buffer layer, such as Ni—P, on a nonmagnetic substrate, prior to sputtering a textured bump layer. A magnetic recording medium comprising a sputter textured metal layer and high coercivity is achieved by employing an underlayer, such as NiAl or FeAl, preferably a composite underlayer containing a chromium or chromium-alloy layer and a NiAl layer, on the sputter textured layer. Advantageously, the buffer layer, underlayer, textured bump layer, magnetic layer and carbon overcoat can be sputter deposited in a single apparatus.
Claims6
A magnetic recording medium, comprising:
- a non-magnetic substrate;
- a sputter deposited buffer layer, having a thickness of about 50 Å to about 300 Å, on the non-magnetic substrate;
- a sputtered metallic bump layer, comprising a plurality of protrusions, formed on the buffer layer;
- a composite underlayer comprising a first layer of chromium or a chromium alloy on the bump layer;
- an intermediate layer comprising nickel-aluminum on the first layer;
- a third layer comprising chromium or a chromium alloy on the intermediate layer;
- and
- a magnetic layer formed on the underlayer, wherein the magnetic recording medium exhibits a coercivity greater than 2500 Oersteads.
A method of manufacturing a magnetic recording medium, which method comprises:
- sputtering a buffer layer on a non-magnetic substrate;
- sputtering a metallic bump layer, comprising a plurality of protrusions, on the buffer layer;
- sputtering an underlayer on the bump layer;
- and
- sputtering a magnetic layer on the underlayer;
- wherein the buffer layer comprises nickel-phosphorous and has a thickness of about 50 Å to about 300 Å, which method further comprises heating the sputtered buffer layer before sputtering the bump layer.
Dependencies are inferred from the claim text.