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

• US 20080182058A1
• Filed: 05/15/2006
• Published: 07/31/2008
• Est. Priority Date: 06/22/1998
• Status: Abandoned Application

• Current Assignee: Target Technology Company LLC
• Original Assignee: Target Technology Company LLC
• Inventors: Nee, Han H.
• Application Number:
  US11/433,945
• Publication Number:
  US 20080182058A1
• Time in Patent Office: Days
• US Class Current: 428/64.5
• 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 2007/24306 transition metal elements of groups 3-10
• CPC Class Codes: G11B 2007/24308 transition metal elements of group 11 (Cu, Ag, Au)
• 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 2007/24316 group 16 elements (i.e. chalcogenides, Se, Te)
• CPC Class Codes: G11B 2007/2432 Oxygen
• 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 7/257 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 7/2585 based on aluminium
• 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

Metal alloy thin films are provided for use in the highly reflective and semi-reflective layers of optical discs. Alloys include silver alloyed with gold, palladium, copper, rhodium, ruthenium, osmium, iridium, and platinum. Other alloys include copper alloys with silver, magnesium, cadmium, aluminum, nickel, beryllium, zirconium and zinc. 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 first pattern of features in at least one major surface;

a semi-reflective layer, said semi-reflective layer including a metal alloy, said metal alloy including silver and copper, wherein the relationship between the amounts of silver and copper in the metal alloy is defined by Ag_xCu_y where 0.95<

x<

0.9999 and 0.0001<

y<

0.05;

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

a high reflective layer.

2. The optical storage medium of claim 1, further comprising an optically recordable dye layer adjacent to said semi-reflective layer.

3. The optical storage medium of claim 2, wherein the first pattern of features includes a spiral groove.

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

y<

0.03.

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

a third layer adjacent to said semi-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.

6. The optical storage medium of claim 5, wherein the first pattern of features includes a spiral groove.

7. The optical storage medium of claim 5, wherein said optically re-recordable material is a phase-changeable material.

8. The optical storage medium of claim 7, 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.

9. The optical storage medium of claim 5, wherein said optically re-recordable material is a magneto-optic material.

10. The optical storage medium of claim 9, 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.