Back to results
US 5,328,813 AGranted
Method for the preparation of optical recording media containing overcoat
AssigneeThe Dow Chemical Company
InventorsAndrew J. G. Strandjord, Steven P. Webb, Floyd E. Woodard
Life of this patent
Estimating the term…
Abstract
Optical storage media based on ablative metals give improved stability and offer improved write-read characteristics when they are overcoated with inorganic oxide, nitride, carbide, hydride, oxynitride or carbohydride to a reflectivity of 40-80% at the media write/read wavelength. Preferably the metal and overcoat are applied by sputter-depositing.
Claims6
A method for producing an optical storage medium comprising:
- a. sputter-depositing a laser recordable thin reflective layer of reflective metal onto at least one surface of a substrate, and
- b. sputter-depositing over the thin laser recordable reflective layer an overcoating layer comprising one or more transparent inorganic materials selected from the group consisting of a nitride or oxynitride of Zr, Hf and Ta to a reflectivity at 830 nm of from 40 to 80%, and
- c. sputter depositing a second overcoating layer consisting of silicon carbohydride over the first overcoating layer.
A method for producing an optical storage medium comprising
- a. sputter-depositing a laser recording thin reflective layer of reflective metal onto at least one surface of a substrate, and
- b. reactively sputtering one or more metals selected from the group consisting of zirconium, tantalum, and hafnium in the presence of a reactant gas source selected from the group consisting of nitrogen or a mixture of oxygen and nitrogen thereby depositing over the thin reflective layer a thin transparent overcoating layer to reflectivity at 830 nm of from 40 to 80%, and
- c. reactively sputtering a second overcoating layer over said first overcoating layer by reactively sputtering silicon carbide in the presence of hydrogen.
Dependencies are inferred from the claim text.