IP Library Granted Patent US 7,656,615
Granted Patent B2
US 7,656,615 · App. 11/588,699 · Granted Feb 2, 2010

Perpendicular magnetic recording disk with a soft magnetic layer having a discrete track recording pattern

View Patent ↗
Loading inventors, assignments & file history…
Monitor This Case
Get email alerts when status or documents change.
Order Certified Copies
Most orders are placed with the USPTO same day — all within 24 business hours.
Order via The Patent Place →
Pre-filled with this patent's details
Quick Facts
Patent No.
US 7,656,615
App. No.
11/588,699
Granted
Feb 2, 2010
Kind
B2
Abstract

A method of forming a discrete track recording pattern on a soft magnetic underlayer of a perpendicular magnetic recording disk. In one embodiment, the soft magnetic underlayer is continuous throughout the discrete track recording pattern.

Claims (20)

1. A perpendicular magnetic recording disk, comprising:

a substrate;

a magnetic recording layer; and

a soft magnetic underlayer disposed between the substrate and the magnetic recording layer, wherein the soft magnetic underlayer has a discrete track recording pattern that does not extend into the plane of the substrate, and wherein the soft magnetic underlayer is continuous throughout the discrete track recording pattern.

2. The perpendicular magnetic recording disk of claim 1 , wherein the discrete track pattern forms a plurality of raised zones and recessed zones.

3. The perpendicular recording disk of claim 2 , wherein the discrete track recording pattern is formed by imprint lithography.

4. The perpendicular recording disk of claim 2 , wherein the raised zone of the discrete track recording pattern has a pitch between 200 to 2000 angstroms.

5. The perpendicular recording disk of claim 1 , wherein the disk substrate comprises a glass material.

6. The perpendicular recording disk of claim 1 , wherein the disk substrate comprises a metallic material.

7. The perpendicular recording disk of claim 6 , further comprising a NiP layer disposed between the disk substrate and the soft magnetic underlayer.

8. The perpendicular recording disk of claim 6 , wherein the NiP layer has a textured surface.

9. The perpendicular recording disk of claim 1 , wherein the soft magnetic underlayer has a textured surface.

10. The perpendicular recording disk of claim 1 , wherein the substrate has a textured surface.

11. The perpendicular magnetic recording disk of claim 1 , wherein the magnetic recording layer has the same discrete track recording pattern as in the soft magnetic underlayer.

12. A disk drive, comprising:

a spindle; and

a disk coupled to the spindle, the disk having a disk substrate, a magnetic recording layer, and a soft magnetic underlayer disposed between the substrate and the magnetic recording layer, wherein a discrete track recording pattern is formed by the soft magnetic underlayer and does not extend into the plane of the substrate, and wherein the soft magnetic underlayer is continuous throughout the discrete track recording pattern.

13. The disk drive of claim 12 , wherein the magnetic recording layer comprises a perpendicular magnetic recording disk.

14. The disk drive of claim 12 , wherein the discrete track recording pattern is formed by imprint lithography.

15. The disk drive of claim 12 , wherein the magnetic recording layer has the same discrete track recording pattern as in the soft magnetic underlayer.

Assignments (7)
RELEASE OF SECURITY INTEREST AT REEL 038710 FRAME 0383 Recorded Feb 8, 2022
From: JPMORGAN CHASE BANK, N.A.
To: WD MEDIA, LLC; WESTERN DIGITAL TECHNOLOGIES, INC.
Reel/Frame 058965/0410 →
RELEASE OF SECURITY INTEREST Recorded Mar 5, 2018
From: U.S. BANK NATIONAL ASSOCIATION, AS COLLATERAL AGENT
To: WD MEDIA, LLC
Reel/Frame 045501/0672 →
SECURITY AGREEMENT Recorded May 16, 2016
From: WD MEDIA, LLC
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 038710/0383 →
SECURITY AGREEMENT Recorded May 16, 2016
From: WD MEDIA, LLC
To: U.S. BANK NATIONAL ASSOCIATION, AS COLLATERAL AGENT
Reel/Frame 038709/0931 →
SECURITY AGREEMENT Recorded May 16, 2016
From: WD MEDIA, LLC
To: JPMORGAN CHASE BANK, N.A., AS COLLATERAL AGENT
Reel/Frame 038709/0879 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Jan 30, 2008
From: WACHENSCHWANZ, DAVID E.; BERTERO, GERARDO A.; TREVES, DAVID; HOMOLA, ANDREW; CHAO, JAMES L.; BAJOREK, CHRISTOPHER H.
To: KOMAG, INC.
Reel/Frame 020440/0044 →
MERGER Recorded Dec 17, 2007
From: KOMAG, INC.
To: WD MEDIA, INC.
Reel/Frame 020257/0216 →