Metal alloys for the reflective or the semi-reflective layer of an optical storage medium

• US 7,018,696 B2
• Filed: 04/16/2004
• Issued: 03/28/2006
• Est. Priority Date: 04/18/2003
• Status: Active Grant

• Current Assignee: Target Technology Company LLC
• Original Assignee: Target Technology Company LLC
• Inventors: Nee, Han H.
• Primary Examiner(s): MULVANEY, ELIZABETH EVANS
• Application Number:
  US10/825,779
• Publication Number:
  US 20040258872A1
• Time in Patent Office: 711 Days
• Field of Search: 428/64.1, 428/64.4, 428/913, 430/270.12, 430/495.1, 430/945
• US Class Current: 428/64.1
• CPC Class Codes: C22C 1/06 with the use of special agents for refining or deoxidising
• 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: C22C 5/10 with cadmium as the next major constituent
• CPC Class Codes: C23C 14/185 by cathodic sputtering
• CPC Class Codes: G11B 2007/0006 adapted for scanning different types of carrier, e.g. CD & DVD
• CPC Class Codes: G11B 2007/0013 for carriers having multiple discrete layers
• 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 2007/2582 based on silver
• CPC Class Codes: G11B 7/00454 involving phase-change effects
• CPC Class Codes: G11B 7/006 Overwriting G11B7/0065 takes precedence
• CPC Class Codes: G11B 7/24038 Multiple laminated recording layers
• CPC Class Codes: G11B 7/24062 Reflective layers
• CPC Class Codes: G11B 7/24085 Pits
• CPC Class Codes: G11B 7/243 comprising inorganic materials only, e.g. ablative layers
• CPC Class Codes: G11B 7/258 of reflective layers
• CPC Class Codes: G11B 7/259 based on silver
• CPC Class Codes: G11B 7/266 Sputtering or spin-coating layers sputtering in general C23C14/24; spin-coating in general B05D1/005
• CPC Class Codes: G11C 13/041 : using photochromic storage elements G11C13/042 takes precedence
• CPC Class Codes: Y10T 428/21 : Circular sheet or circular blank
• CPC Class Codes: Y10T 428/24521 : with component conforming to contour of nonplanar surface
• CPC Class Codes: Y10T 428/24545 : Containing metal or metal compound

Abstract

A silver-based alloy thin film is provided for the highly reflective or semi-reflective coating layer of optical discs. Elements that can be added to silver to produce useful silver alloys include zinc, aluminum, copper, manganese, germanium, yttrium, bismuth, scandium, and cobalt. These alloys have moderate to high reflectivity and reasonable corrosion resistance in the ambient environment.

Claims

1. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver and yttrium, wherein the relationship between the amounts of silver and yttrium in the metal alloy is defined by Ag_xY_w where 0.9500<

x<

0.9999 and 0.0001<

w<

0.05.

2. The optical storage medium of claim 1, wherein 0.001<

w<

0.03.

3. The optical storage medium of claim 1, wherein said first reflective layer is high reflective layer.

4. The optical storage medium of claim 1, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

5. The optical storage medium of claim 4, wherein said second reflective layer includes said metal alloy.

6. The optical storage medium of claim 4, wherein the first pattern of features includes a spiral groove.

7. The optical storage medium of claim 4, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

8. The optical storage medium of claim 7, wherein said optically re-recordable material is a phase-changeable material.

9. The optical storage medium of claim 8, wherein said optically re-recordable material further comprises a phase changeable material 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.

10. The optical storage medium of claim 7, wherein said optically re-recordable material is a magneto-optic material.

11. The optical storage medium of claim 10, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

12. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver and scandium, wherein the relationship between the amounts of silver and scandium in the metal alloy is defined by Ag_xSc_w where 0.9500<

x<

0.9999 and 0.0001<

w<

0.05.

13. The optical storage medium of claim 12, wherein 0.001<

w<

0.03.

14. The optical storage medium of claim 12, wherein said first reflective layer is high reflective layer.

15. The optical storage medium of claim 12, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

16. The optical storage medium of claim 15, wherein said second reflective layer includes said metal alloy.

17. The optical storage medium of claim 15, wherein the first pattern of features includes a spiral groove.

18. The optical storage medium of claim 15, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

19. The optical storage medium of claim 19, wherein said optically re-recordable material is a phase-changeable material.

20. The optical storage medium of claim 19, wherein said optically re-recordable material further comprises a phase changeable material 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.

21. The optical storage medium of claim 19, wherein said optically re-recordable material is a magneto-optic material.

22. The optical storage medium of claim 21, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

23. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver and bismuth, wherein the relationship between the amounts of silver and bismuth in the metal alloy is defined by Ag_xBi_w where 0.9500<

x<

0.9999 and 0.0001<

w<

0.05.

24. The optical storage medium of claim 23, wherein 0.001<

w<

0.03.

25. The optical storage medium of claim 23, wherein said first reflective layer is high reflective layer.

26. The optical storage medium of claim 23, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

27. The optical storage medium of claim 26, wherein said second reflective layer includes said metal alloy.

28. The optical storage medium of claim 26, wherein the first pattern of features includes a spiral groove.

29. The optical storage medium of claim 26, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

30. The optical storage medium of claim 29, wherein said optically re-recordable material is a phase-changeable material.

31. The optical storage medium of claim 30, wherein said optically re-recordable material further comprises a phase changeable material 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.

32. The optical storage medium of claim 29, wherein said optically re-recordable material is a magneto-optic material.

33. The optical storage medium of claim 32, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

82. The optical storage medium of claim 30, wherein said second reflective layer includes said metal alloy.

83. The optical storage medium of claim 30, wherein the first pattern of features includes a spiral groove.

84. The optical storage medium of claim 30, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

85. The optical storage medium of claim 84, wherein said optically re-recordable material is a phase-changeable material.

86. The optical storage medium of claim 85, wherein said optically re-recordable material further comprises a phase changeable material 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.

87. The optical storage medium of claim 84, wherein said optically re-recordable material is a magneto-optic material.

88. The optical storage medium of claim 87, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

34. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver, copper, and element A, where A is selected from the group of elements consisting of yttrium, scandium, or bismuth, wherein the relationship between the amounts of silver, copper, and element A in the metal alloy is defined by Ag_xCu_z,A_w where 0.85<

x<

0.9998, 0.0001<

z<

0.10, and 0.0001<

w<

0.05.

35. The optical storage medium of claim 34, wherein 0.001<

w<

0.03.

36. The optical storage medium of claim 34, wherein said first reflective layer is high reflective layer.

37. The optical storage medium of claim 34, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

38. The optical storage medium of claim 37, wherein said second reflective layer includes said metal alloy.

39. The optical storage medium of claim 37, wherein the first pattern of features includes a spiral groove.

40. The optical storage medium of claim 37, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

41. The optical storage medium of claim 40, wherein said optically re-recordable material is a phase-changeable material.

42. The optical storage medium of claim 41, wherein said optically re-recordable material further comprises a phase changeable material 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.

43. The optical storage medium of claim 40, wherein said optically re-recordable material is a magneto-optic material.

44. The optical storage medium of claim 43, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

45. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver, copper, and magnesium, wherein the relationship between the amounts of silver, copper, and magnesium in the metal alloy is defined by Ag_xCu_zMg_w where 0.85<

x<

0.9998, 0.0001<

z<

0.10, and 0.0001<

w<

0.05.

46. The optical storage medium of claim 45, wherein 0.001<

w<

0.03.

47. The optical storage medium of claim 45, wherein said first reflective layer is high reflective layer.

48. The optical storage medium of claim 45, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

49. The optical storage medium of claim 48, wherein said second reflective layer includes said metal alloy.

50. The optical storage medium of claim 48, wherein the first pattern of features includes a spiral groove.

51. The optical storage medium of claim 48, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

52. The optical storage medium of claim 51, wherein said optically re-recordable material is a phase-changeable material.

53. The optical storage medium of claim 52, wherein said optically re-recordable material further comprises a phase changeable material 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.

54. The optical storage medium of claim 51, wherein said optically re-recordable material is a magneto-optic material.

55. The optical storage medium of claim 54, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

56. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver, copper, and cobalt, wherein the relationship between the amounts of silver, copper, and cobalt in the metal alloy is defined by Ag_x,Cu_zCo_w where 0.85<

x<

0.9998, 0.0001<

z<

0.10, and 0.0001<

w<

0.05.

57. The optical storage medium of claim 56, wherein 0.001<

w<

0.03.

58. The optical storage medium of claim 56, wherein said first reflective layer is high reflective layer.

59. The optical storage medium of claim 56, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

60. The optical storage medium of claim 59, wherein said second reflective layer includes said metal alloy.

61. The optical storage medium of claim 59, wherein the first pattern of features includes a spiral groove.

62. The optical storage medium of claim 59, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

63. The optical storage medium of claim 59, wherein said optically re-recordable material is a phase-changeable material.

64. The optical storage medium of claim 63, wherein said optically re-recordable material further comprises a phase changeable material 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—

S—

Se, In—

Se—

Tl—

Co, Bi—

Ge, Bi—

Ge—

Sb, Bi—

Ge—

Te, and Si—

Te—

Sn.

65. The optical storage medium of claim 59, wherein said optically re-recordable material is a magneto-optic material.

66. The optical storage medium of claim 65, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

67. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver, zinc, and magnesium, wherein the relationship between the amounts of silver, zinc, and magnesium in the metal alloy is defined by Ag_xZn_yMg_w where 0.8000<

x<

0.9998, 0.0001<

y<

0.15, and 0.0001<

w<

0.05.

68. The optical storage medium of claim 67, wherein 0.001<

w<

0.03.

69. The optical storage medium of claim 67, wherein said first reflective layer is high reflective layer.

70. The optical storage medium of claim 67, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.

71. The optical storage medium of claim 70, wherein said second reflective layer includes said metal alloy.

72. The optical storage medium of claim 70, wherein the first pattern of features includes a spiral groove.

73. The optical storage medium of claim 70, further comprising:

a third layer adjacent said first reflective layer, said third layer including a dielectric material;

a fourth layer, said fourth layer including an optically re-recordable material; and

a fifth layer, said fifth layer including a dielectric material.

74. The optical storage medium of claim 73, wherein said optically re-recordable material is a phase-changeable material.

75. The optical storage medium of claim 74, wherein said optically re-recordable material further comprises a phase changeable material 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.

76. The optical storage medium of claim 73, wherein said optically re-recordable material is a magneto-optic material.

77. The optical storage medium of claim 76, wherein said optically re-recordable material further comprises a magneto-optic material selected from the group consisting of Tb—

Fe—

Co and Gd—

Tb—

Fe.

78. An optical storage medium, comprising:

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

a first reflective layer adjacent said feature pattern, said first reflective layer including a metal alloy, said metal alloy including silver, zinc, and cobalt, wherein the relationship between the amounts of silver, zinc, and cobalt in the metal alloy is defined by Ag_xZn_yCo_w where 0.8000<

x<

0.9998, 0.0001<

y<

0.15, and 0.0001<

w<

0.05.

79. The optical storage medium of claim 78, wherein 0.001<

w<

0.03.

80. The optical storage medium of claim 78, wherein said first reflective layer is high reflective layer.

81. The optical storage medium of claim 78, further comprising:

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

a second reflective layer, wherein said first reflective layer is a semi-reflective layer and said second reflective layer is a high reflective layer.