Reverse optical mastering for data storage disks

• US 20010016301A1
• Filed: 05/07/2001
• Published: 08/23/2001
• Est. Priority Date: 04/06/1998
• Status: Active Grant

• Current Assignee: Max Blu Technologies, LLC (IP Investments Group LLC)
• Original Assignee: Imation Corporation (Glassbridge Enterprises, Inc.)
• Inventors: Edwards, Jathan D.
• Granted Patent: US 6,728,196 B2
• Time in Patent Office: Days
• US Class Current: 430/321
• CPC Class Codes: G11B 23/0085 intermediate mediums using a photosensitive material, e.g. photo-resist
• CPC Class Codes: G11B 7/24 Record carriers characterised by shape, structure or physical properties, or by the selection of the material characterised by the arrangement of information on the carrier G11B7/007
• CPC Class Codes: G11B 7/24091 Combinations of pits and tracks with specific interrelation
• CPC Class Codes: G11B 7/261 Preparing a master, e.g. exposing photoresist, electroforming
• CPC Class Codes: G11B 7/263 Preparing and using a stamper, e.g. pressing or injection molding substrates production of optical record carriers, e.g. optical discs B29D17/005
• CPC Class Codes: Y10S 425/81 Sound record

Abstract

A data storage master disk and method of making a data storage master disk. The data storage disk master is for use in a data storage disk replication process. The data storage disk molding processes produces replica disks having a surface relief pattern with replica lands and replica grooves. The method includes providing a master substrate. The master substrate is at least partially covered with a layer of photosensitive material. A surface relief pattern having master lands and master grooves is recorded in the data storage disk master, including the steps of exposing and developing the photosensitive material. The exposing and developing of a specified thickness of photosensitive material is controlled to form master grooves extending down to a substrate interface between the master substrate and the layer of photosensitive material, such that the width of the master grooves at the substrate interface corresponds to a desired width of the replica lands.

Claims

1. A master disk comprising:

a master substrate;

a layer of photosensitive material covering at least a portion of the master substrate, the photosensitive material including a surface relief pattern in the form of a track pattern defined by adjacent master lands and master grooves, wherein the master grooves extend down to the master substrate, the master grooves including a master groove bottom and the master lands including a master land top, wherein the master groove bottom is wider than the master land top.

2. The master disk of

claim 1

, wherein the master groove bottom is generally flat.

3. The master disk of

claim 1

, wherein the master groove bottoms are flat relative to the master land tops.

4. The master disk of

claim 1

, wherein the master groove bottoms are level with each other.

5. The master disk of

claim 1

, wherein the master groove bottoms are wide and flat relative to the master land tops.

6. The master disk of

claim 1

, wherein the master groove bottoms include sharp corners.

7. The master disk of

claim 1

, wherein the master grooves include a groove depth which is approximate the thickness of the photosensitive material.

8. The master disk of

claim 1

, wherein the master grooves includes a groove depth which is greater than 50 nanometers.

9. The master disk of

claim 1

, wherein the track pitch is less than 425 nanometers, the width of the master groove bottom is greater than 100 nanometers.

10. The master disk of

claim 9

, wherein the width of the master groove bottom is greater than 250 nanometers.

11. The master disk of

claim 9

, wherein the groove depth is greater than 50 nanometers.

12. A disk made from a replication process which includes a master disk having a data layer formed over a master substrate, the disk comprising:

a replica substrate having a first major surface and a second major surface, the first major surface including a surface relief pattern in the form of a track pattern defined by adjacent lands and grooves, the track pattern having a track pitch less than 425 nanometers, wherein the grooves extend down into the replica substrate, the grooves including a groove bottom and the lands including a land top, wherein the land top is flat.

13. The disk of

claim 12

, wherein the land top has a width greater than 35% of track pitch.

14. The disk of

claim 12

, wherein the groove depth is greater than 50 nanometers.

15. The disk of

claim 14

, wherein the land width is greater than 100 nanometers.

16. The disk of

claim 12

, wherein the land top is smooth.

17. The disk of

claim 13

, further wherein the land top has sharp edges.

18. The disk of

claim 12

, wherein the land tops are level with each other, such that the flatness of first major surface of the replica disk is defined by master substrate flatness.

19. The disk of

claim 12

, wherein the land tops are level and at the same elevation relative to the second major surface.

20. A stamper comprising:

a stamper substrate having a first major surface and second major surface, the first major surface including a surface relief pattern in the form of a track pattern defined by adjacent stamper lands and stamper grooves, wherein the grooves extend down into the stamper substrate, the stamper grooves including a stamper groove bottom and the stamper lands including a stamper land top, wherein the stamper groove bottom is wider than the stamper land top.

21. The stamper of

claim 20

, wherein the stamper groove bottom is generally flat.

22. The stamper of

claim 20

, wherein the master groove bottoms are flat relative to the master land tops.

23. The stamper of

claim 20

, wherein the master groove bottoms are level with each other.

24. The stamper of

claim 20

, wherein the master groove bottoms are wide and flat relative to the master land tops.

25. The stamper of

claim 20

, wherein the master groove bottoms include sharp corners.

26. The stamper of

claim 20

, wherein the master grooves includes a groove depth which is greater than 50 nanometers.

27. The stamper of

claim 20

, wherein the track pitch is less than 425 nanometers, the width of the master groove bottom is greater than 100 nanometers.

28. The stamper of

claim 27

, wherein the width of the master groove bottom is greater than 250 nanometers.

29. The stamper of

claim 27

, wherein the groove depth is greater than 50 nanometers.