Double-sided hybrid optical disk with surface topology

• US 20020136984A1
• Filed: 03/25/2002
• Published: 09/26/2002
• Est. Priority Date: 01/16/2001
• Status: Active Grant

• Current Assignee: Clearwater Innovations LLC
• Original Assignee: Silicon Valley Bank (SVB Financial Group)
• Inventors: Medower, Brian S., Blankenbeckler, David L., Redmond, Ian R., Davies, David H.
• Granted Patent: US 6,908,725 B2
• Time in Patent Office: Days
• US Class Current: 430/270.13
• CPC Class Codes: G11B 2007/24304 group 2 or 12 elements (e.g. Be, Ca, Mg, Zn, Cd)
• CPC Class Codes: G11B 2007/2431 group 13 elements (B, Al, Ga, In)
• CPC Class Codes: G11B 2007/24312 group 14 elements (e.g. Si, Ge, Sn)
• CPC Class Codes: G11B 2007/24314 group 15 elements (e.g. Sb, Bi)
• CPC Class Codes: G11B 2007/2571 containing group 14 elements except carbon (Si, Ge, Sn, Pb)
• CPC Class Codes: G11B 2007/25713 containing nitrogen
• CPC Class Codes: G11B 2007/25715 containing oxygen
• CPC Class Codes: G11B 7/0079 Zoned data area, e.g. having different data structures or formats for the user data within data layer, Zone Constant Linear Velocity [ZCLV], Zone Constant Angular Velocity [ZCAV], carriers with RAM and ROM areas
• CPC Class Codes: G11B 7/24038 Multiple laminated recording layers
• CPC Class Codes: G11B 7/243 comprising inorganic materials only, e.g. ablative layers
• CPC Class Codes: G11B 7/2531 comprising glass
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• CPC Class Codes: G11B 7/2542 consisting essentially of organic resins
• CPC Class Codes: G11B 7/257 of layers having properties involved in recording or reproduction, e.g. optical interference layers or sensitising layers or dielectric layers, which are protecting the recording layers
• CPC Class Codes: G11B 7/2572 consisting essentially of organic materials
• CPC Class Codes: G11B 7/258 of reflective layers
• CPC Class Codes: G11B 7/26 Apparatus or processes specially adapted for the manufacture of record carriers
• CPC Class Codes: Y10S 430/146 Laser beam

Abstract

An optical disk has a multi-layer tuned optical coating overlying both small bumps to store pre-recorded information and lands onto which information is written to and read. The optical coating includes a phase-change metal/alloy layer formed over the disk substrate and a dielectric layer formed over the phase-change layer. An optical disk according to the invention has specific topological features and sizes.

Claims

1. An optical disk, comprising:

a substrate having a circular first surface and an opposing circular second surface, wherein the outer diameter of the first and second surface is approximately less than 50 mm;

a spiral pattern of bumps on a first portion of the circular first surface, wherein information is stored on and read from the bumps;

a spiral land on a second portion of the circular first surface, wherein information is written to and read from the land; and

a continuous multi-layer optical coating overlaying the bumps and land on the circular first surface, wherein the optical coating comprises;

a metal/alloy layer comprising tin, antimony and an element selected from the group consisting of indium, germanium, aluminum, and zinc; and

a dielectric layer overlaying the metal/alloy layer.

2. The disk of claim 1, wherein the outer diameter of the first and second surface is approximately 32 mm or less.

3. The disk of claim 1, wherein the thickness of the substrate is approximately 0.6 mm±

0.03 mm.

4. The disk of claim 1, wherein the width of the bumps is between approximately 200 nm and 250 nm, the width measured at half-width full-max.

5. The disk of claim 1, wherein the width of the bumps is 30%±

3% of the track pitch of the bumps, the track pitch being the distance between the centerlines of adjacent bumps along the radial direction.

6. The disk of claim 1, wherein the average distance between centerlines of adjacent bumps along the radial direction is 0.74 μ

m±

0.03 μ

m.

7. The disk of claim 1, wherein the height of the bumps is between approximately 80 nm and 90 nm.

8. The disk of claim 1, wherein the bumps comprise sidewalls at an angle between 30°

and 50°

, as measured along the first circular surface.

9. The disk of claim 8, wherein the angle is approximately 45°

.

10. The disk of claim 1, wherein the distance between two of the bumps in a radially adjacent direction is between approximately 485 nm and 545 nm, measured at full width half max.

11. The disk of claim 1, wherein the length of the bumps, covered by the optical coating, are multiples of 179 nm, the shortest length being a third multiple and the longest length being a fourteenth multiple.

12. The disk of claim 1, wherein the height of the land is between approximately 80 nm and 90 nm.

13. The disk of claim 1, wherein the width of the land is approximately 400 nm±

50 nm, the width measured at half-width full-max.

14. The disk of claim 1, wherein the width of the land is approximately 55% of the track pitch of the land, the track pitch being the distance between the centerlines of radially adjacent portions of the land.

15. The disk of claim 1, wherein the average distance between centerlines of radially adjacent portions of the land is between approximately 0.70 μ

m to 0.78 μ

m.

16. The disk of claim 1, wherein the land comprises sidewalls at an angle between 30°

and 50°

, as measured along the first circular surface.

17. The disk of claim 16, wherein the angle is approximately 45°

.

18. The disk of claim 1, wherein the land has sinusoidal wobbles.

19. The disk of claim 18, wherein the amplitude of the wobbles along the radial direction is 55±

15 nm.

20. The disk of claim 18, wherein the amplitude of the wobbles along the radial direction is 7.5%±

2% of the track pitch of the land, the track pitch being the distance between the centerlines of radially adjacent portions of the land.

21. The disk of claim 18, wherein the frequency of the wobbles is approximately 128 kHz.

22. The disk of claim 18, further comprising high frequency wobble marks (HFWMs) along the wobbles.

23. The disk of claim 22, wherein the frequency of the HFWMs is approximately 3 to 5 times the frequency of the wobbles.

24. The disk of claim 22, wherein the frequency of the HFWMs is between approximately 384 kHz to 641 kHz.

25. The disk of claim 18, wherein the amplitude of the wobbles and HFWMs is within ±

25% of each other.

26. The disk of claim 1, wherein the dielectric layer comprises silicon oxynitride.