METAL ALLOYS FOR THE REFLECTIVE OR SEMI-REFLECTIVE LAYER OF AN OPTICAL STORAGE MEDIUM

• US 20060172107A1
• Filed: 03/31/2006
• Published: 08/03/2006
• Est. Priority Date: 06/22/1998
• Status: Active Grant

• Current Assignee: Target Technology Company LLC
• Original Assignee: Target Technology Company LLC
• Inventors: Nee, Han H.
• Granted Patent: US 7,384,677 B2
• Time in Patent Office: Days
• US Class Current: 428/64.400
• CPC Class Codes: C22C 5/06 Alloys based on silver
• CPC Class Codes: C22C 5/08 with copper as the next major constituent
• CPC Class Codes: C22F 1/14 of noble metals or alloys based thereon
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: G11B 11/10584 characterised by the form, e.g. comprising mechanical protection elements
• CPC Class Codes: G11B 11/10586 characterised by the selection of the material
• 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 2007/24316 group 16 elements (i.e. chalcogenides, Se, Te)
• CPC Class Codes: G11B 7/00454 involving phase-change effects
• CPC Class Codes: G11B 7/00455 involving reflectivity, absorption or colour changes
• 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 7/246 containing dyes
• CPC Class Codes: G11B 7/2534 polycarbonates [PC]
• 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 7/258 of reflective layers
• CPC Class Codes: G11B 7/259 based on silver
• CPC Class Codes: G11B 7/2595 based on gold
• CPC Class Codes: Y10T 428/21 Circular sheet or circular blank

Abstract

A silver-based alloy thin film is provided for the highly reflective or the semi-reflective layer of optical discs. Alloy additions to silver include magnesium, gold, rhodium, ruthenium, osmium, platinum, palladium, copper, silicon, cadmium, tin, lithium, nickel, cobalt, manganese, indium, chromium, antimony, gallium, boron, molybdenum, zirconium, beryllium, titanium, aluminum, germanium and zinc. These alloys have moderate to high reflectivity and reasonable corrosion resistance in ambient environments.

Claims

1. An optical storage medium, comprising:

a first layer having a pattern of features in at least one major surface;

a semi-reflective layer adjacent the pattern of features in said first layer, the semi-reflective layer including a metal alloy, said metal alloy including silver, zinc and beryllium, wherein the relationship between the amounts of silver, zinc and beryllium in said metal alloy is defined by Ag_xZn_yBe_z, wherein 0.8<

x<

0.9998, 0.0001<

y<

0.1 and 0.0001<

z<

0.1;

a second layer having a pattern of features in at least one major surface; and

a reflective layer adjacent the pattern of features in said second layer.

2. The optical storage medium according to claim 1, wherein 0.90<

x<

0.998, 0.001<

y<

0.05, and 0.001<

z<

0.05.

3. The optical storage medium according to claim 1, wherein said pattern of features includes a series of pits and lands.

4. The optical storage medium according to claim 1, wherein said pattern of features includes a groove.

5. The optical storage medium according to claim 4, wherein said groove is continuous.

6. The optical storage medium according to claim 1, including a recordable layer, wherein said recordable layer is adjacent to said reflective layer.

7. The optical storage medium according to claim 6, wherein said recordable layer includes a dye.

8. The optical storage medium according to claim 1, including a re-recordable layer, wherein said re-recordable layer is adjacent to said reflective layer.

9. The optical storage medium according to claim 8, wherein said re-recordable layer includes a phase-changeable material.

10. The optical storage medium according to claim 9, wherein said phase-changeable material is selected from the group consisting of Ge—

Sb—

Te, As—

In—

Sb—

Te, Cr—

Ge—

Sb—

Te, As—

Te—

Ge, Te—

Ge—

Sn, Te—

Ge—

Sn—

O, Te—

Se, Sn—

Te—

Se, Te—

Ge—

Sn—

Au, Ge—

Sb—

Te, Sb—

Te—

Se, In—

Se—

Tl, In—

Sb, In—

Sb—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

11. The optical storage medium according to claim 8, wherein said re-recordable layer includes a magneto-optic material.

12. The optical storage medium according to claim 11, wherein said magneto-optic material is selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

13. An optical storage medium, comprising:

a first layer having a pattern of features in at least one major surface;

a semi-reflective layer adjacent the pattern of features in said first layer, the semi-reflective layer including a metal alloy, said metal alloy including silver, indium, and beryllium wherein the relationship between the amounts of silver, indium and beryllium in said metal alloy is defined by Ag_xIn_qBe_z, wherein 0.8<

x<

0.9998, 0.0001<

q <

0.1 and 0.0001<

z<

0.1;

a second layer having a pattern of features in at least one major surface; and

a reflective layer adjacent the pattern of features in said second layer.

14. The optical storage medium according to claim 13, wherein 0.90<

x<

0.998, 0.001<

q <

0.05, and 0.001<

z<

0.05.

15. The optical storage medium according to claim 13, wherein said pattern of features includes a series of pits and lands.

16. The optical storage medium according to claim 13, wherein said pattern of features includes a groove.

17. The optical storage medium according to claim 16, wherein said groove is continuous.

18. The optical storage medium according to claim 13, including a recordable layer, wherein said recordable layer is adjacent to said reflective layer.

19. The optical storage medium according to claim 18, wherein said recordable layer includes a dye.

20. The optical storage medium according to claim 13, including a re-recordable layer, wherein said re-recordable layer is adjacent to said reflective layer.

21. The optical storage medium according to claim 18, wherein said re-recordable layer includes a phase-changeable material.

22. The optical storage medium according to claim 21, wherein said phase-changeable material is selected from the group consisting of Ge—

Sb—

Te, As—

In—

Sb—

Te, Cr—

Ge—

Sb—

Te, As—

Te—

Ge, Te—

Ge—

Sn, Te—

Ge—

Sn—

O, Te—

Se, Sn—

Te—

Se, Te—

Ge—

Sn—

Au, Ge—

Sb—

Te, Sb—

Te—

Se, In—

Se—

Tl, In—

Sb, In—

Sb—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

23. The optical storage medium according to claim 18, wherein said re-recordable layer includes a magneto-optic material.

24. The optical storage medium according to claim 23, wherein said magneto-optic material is selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

25. An optical storage medium, comprising:

a first layer having a pattern of features in at least one major surface;

a semi-reflective layer adjacent the pattern of features in said first layer, the semi-reflective layer including a metal alloy, said metal alloy including silver, beryllium and at least one element A selected from the list consisting of chromium, titanium, cadmium, lithium, nickel, cobalt, aluminum and germanium wherein the relationship between the amounts of silver, beryllium and element A said metal alloy is defined by Ag_xBe_zA_a, wherein 0.8<

x<

0.9998, 0.0001<

z<

0.1 and 0.0001<

a <

0.1;

a second layer having a pattern of features in at least one major surface; and

a reflective layer adjacent the pattern of features in said second layer.

26. The optical storage medium according to claim 25, wherein 0.90<

x<

0.998, 0.001<

z<

0.05, 0.001<

a<

0.05.

27. The optical storage medium according to claim 25, wherein said pattern of features includes a series of pits and lands.

28. The optical storage medium according to claim 25, wherein said pattern of features includes a groove.

29. The optical storage medium according to claim 28, wherein said groove is continuous.

30. The optical storage medium according to claim 25, including a recordable layer, wherein said recordable layer is adjacent to said reflective layer.

31. The optical storage medium according to claim 30, wherein said recordable layer includes a dye.

32. The optical storage medium according to claim 25, including a re-recordable layer, wherein said re-recordable layer is adjacent to said reflective layer.

33. The optical storage medium according to claim 32, wherein said re-recordable layer includes a phase-changeable material.

34. The optical storage medium according to claim 33, wherein said phase-changeable material is selected from the group consisting of Ge—

Sb—

Te, As—

In—

Sb—

Te, Cr—

Ge—

Sb—

Te, As—

Te—

Ge, Te—

Ge—

Sn, Te—

Ge—

Sn—

O, Te—

Se, Sn—

Te—

Se, Te—

Ge—

Sn—

Au, Ge—

Sb—

Te, Sb—

Te—

Se, In—

Se—

Tl, In—

Sb, In—

Sb—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

35. The optical storage medium according to claim 32, wherein said re-recordable layer includes a magneto-optic material.

36. The optical storage medium according to claim 35, wherein said magneto-optic material is selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

37. An optical storage medium, comprising:

a first layer having a pattern of features in at least one major surface;

a semi-reflective layer adjacent the pattern of features in said first layer, the semi-reflective layer including a metal alloy, said metal alloy including silver, indium and magnesium, wherein the relationship between the amounts of silver, indium and magnesium in said metal alloy is defined by Ag_xIn_qMg_m, wherein 0.8<

x<

0.9998, 0.0001<

q<

0.1 and 0.0001<

m<

0.1;

a second layer having a pattern of features in at least one major surface; and

a reflective layer adjacent the pattern of features in said second layer.

38. The optical storage medium according to claim 37, wherein 0.90<

x<

0.998, 0.001<

q<

0.05, and 0.001<

m<

0.05.

39. The optical storage medium according to claim 37, wherein said pattern of features includes a series of pits and lands.

40. The optical storage medium according to claim 37, wherein said pattern of features includes a groove.

41. The optical storage medium according to claim 37, wherein said groove is continuous.

42. The optical storage medium according to claim 40, including a recordable layer, wherein said recordable layer is adjacent to said reflective layer.

43. The optical storage medium according to claim 42, wherein said recordable layer includes a dye.

44. The optical storage medium according to claim 37, including a re-recordable layer, wherein said re-recordable layer is adjacent to said reflective layer.

45. The optical storage medium according to claim 44, wherein said re-recordable layer includes a phase-changeable material.

46. The optical storage medium according to claim 45, wherein said phase-changeable material is selected from the group consisting of Ge—

Sb—

Te, As—

In—

Sb—

Te, Cr—

Ge—

Sb—

Te, As—

Te—

Ge, Te—

Ge—

Sn, Te—

Ge—

Sn—

O, Te—

Se, Sn—

Te—

Se, Te—

Ge—

Sn—

Au, Ge—

Sb—

Te, Sb—

Te—

Se, In—

Se—

Tl, In—

Sb, In—

Sb—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

47. The optical storage medium according to claim 44, wherein said re-recordable layer includes a magneto-optic material.

48. The optical storage medium according to claim 47, wherein said magneto-optic material is selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

49. An optical storage medium, comprising:

a first layer having a pattern of features in at least one major surface;

a semi-reflective layer adjacent the pattern of features in said first layer, the semi-reflective layer including a metal alloy, said metal alloy including silver, indium, and at least one element A selected from the list consisting of antimony, gallium, silicon, boron, and molybdenum wherein the relationship between the amounts of silver, magnesium and element A is defined by Ag_xIn_qB_b, wherein 0.9<

x<

0.9998, 0.0001<

q<

0.05 and 0.0001<

b<

0.05;

a second layer having a pattern of features in at least one major surface; and

a reflective layer adjacent the pattern of features in said second layer.

50. The optical storage medium according to claim 49, wherein 0.90<

x<

0.998, 0.001<

q<

0.05, and 0.001<

b<

0.05.

51. The optical storage medium according to claim 49, wherein said pattern of features includes a series of pits and lands.

52. The optical storage medium according to claim 49, wherein said pattern of features includes a groove.

53. The optical storage medium according to claim 52, wherein said groove is continuous.

54. The optical storage medium according to claim 49, including a recordable layer, wherein said recordable layer is adjacent to said reflective layer.

55. The optical storage medium according to claim 54, wherein said recordable layer includes a dye.

56. The optical storage medium according to claim 49, including a re-recordable layer, wherein said re-recordable layer is adjacent to said reflective layer.

57. The optical storage medium according to claim 56, wherein said re-recordable layer includes a phase-changeable material.

58. The optical storage medium according to claim 57, wherein said phase-changeable material is selected from the group consisting of Ge—

Sb—

Te, As—

In—

Sb—

Te, Cr—

Ge—

Sb—

Te, As—

Te—

Ge, Te—

Ge—

Sn, Te—

Ge—

Sn—

O, Te—

Se, Sn—

Te—

Se, Te—

Ge—

Sn—

Au, Ge—

Sb—

Te, Sb—

Te—

Se, In—

Se—

Tl, In—

Sb, In—

Sb—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

59. The optical storage medium according to claim 56, wherein said re-recordable layer includes a magneto-optic material.

60. The optical storage medium according to claim 59, wherein said magneto-optic material is selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.