Back to results
US 6,171,674 B2Granted
Hard carbon coating for magnetic recording medium
AssigneeSemiconductor Energy Laboratory Co., Ltd.
InventorsShunpei Yamazaki, Kenji Itoh, Shigenori Hayashi
Life of this patent
Estimating the term…
Abstract
In an apparatus for fabricating a carbon coating, an object such as a magnetic recording medium is disposed on a side of an electrode connected to a high-frequency power supply. Ultrasonic vibrations are supplied to the object. Discharge is generated between the electrode connected to the high-frequency power supply and a grounded electrode to fabricate a carbon coating on the surface of the object. Also, an electrode interval is set to 6 mm or less, pressure between the electrodes is set to 15 Torr to 100 Torr, whereby high-density plasma is generated to form an ion sheath on an anode side. Therefore, a coating is fabricated on the surface of the object by bombardment of ions.
Claims175
A magnetic recording medium comprising:
- a protective film provided over said magnetic recording medium and comprising a hard carbon coating,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less, and
- wherein said hard carbon coating has a thickness of 500 Å or less.
A magnetic recording medium comprising:
- a protective film provided over said magnetic recording medium and comprising a hard carbon coating containing hydrogen,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating has a thickness of 500 Å or less.
A magnetic recording medium comprising:
- a substrate made of organic resin or industrial plastic;
- a protective film provided over said magnetic recording medium having said substrate and comprising a hard carbon coating,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating has a thickness of 500 Å or less.
1 more element
A magnetic recording medium comprising:
- a protective film provided over said magnetic recording medium and comprising a hard carbon coating,
- wherein said hard carbon coating is formed by plasma CVD,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
1 more element
A magnetic recording medium comprising:
- a protective film provided over said magnetic recording medium having a metal magnetic layer and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic recording medium comprising:
- a protective film provided over said magnetic recording medium and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein said hard carbon coating contains at least one element selected from the group consisting of Si, B, N, P and F in a concentration of 20 atoms % or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic recording medium comprising:
- a protective film provided on a surface of said magnetic recording medium and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical magnetic disk comprising:
- a protective film provided over said optical magnetic disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical magnetic disk comprising:
- a protective film provided over said optical magnetic disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating is formed by plasma-CVD.
1 more element
An optical magnetic disk comprising:
- a protective film provided over said optical magnetic disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein said hard carbon coating contains at least one element selected from the group consisting of Si, B, N, P and F,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
1 more element
An optical magnetic disk comprising:
- a protective film provided on a surface of said optical magnetic disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical magnetic disk comprising:
- a protective film provided over said optical magnetic disk having a metal magnetic layer and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical magnetic disk comprising:
- a substrate made of organic resin or industrial plastic;
- a protective film provided over said optical magnetic disk having said substrate and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
1 more element
A compact disk comprising:
- a protective film provided over said compact disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein said hard carbon coating contains at least one element selected from the group consisting of Si, B, N, P and F,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
1 more element
A compact disk comprising:
- a protective film provided over said compact disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A compact disk comprising:
- a protective film provided on a surface of said compact disk and comprising a hard carbon coating,
- wherein a thickness of said hard carbon coating is less than 500 Å,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A compact disk comprising:
- a protective film provided over said compact disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating is formed by plasma-CVD.
A compact disk comprising:
- a substrate made of organic resin or industrial plastic;
- a protective film provided over said compact disk having said substrate and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A compact disk comprising:
- a protective film provided over said compact disk having a metal magnetic layer and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A compact disk comprising:
- a protective film provided over said compact disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating contains hydrogen.
An optical magnetic disk comprising:
- a protective film provided over said optical magnetic disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating contains hydrogen.
An optical disk comprising:
- a protective film provided over said optical disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical disk comprising:
- a protective film provided over said optical disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating contains hydrogen.
An optical disk comprising:
- a substrate made of organic resin or industrial plastic;
- a protective film provided over said optical disk having said substrate and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical disk comprising:
- a protective film provided over said optical disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating is formed by plasma-CVD.
An optical disk comprising:
- a protective film provided over said optical disk having a metal magnetic layer and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical disk comprising:
- a protective film provided on a surface of said optical disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic tape comprising:
- a protective film provided over said magnetic tape and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic tape comprising:
- a protective film provided over said magnetic tape and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating contains hydrogen.
A magnetic tape comprising:
- a substrate made of organic resin or industrial plastic;
- a protective film provided over said magnetic tape having said substrate and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic tape comprising:
- a protective film provided over said magnetic tape and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less,
- wherein said hard carbon coating is formed by plasma-CVD.
A magnetic tape comprising:
- a protective film provided over said magnetic tape having a metal magnetic layer and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
A magnetic tape comprising:
- a protective film provided on a surface of said magnetic tape and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein the number of pin-holes in said hard carbon coating is 30/mm2 or less.
An optical disk comprising:
- a protective film provided over said optical disk and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein said number of pin-holes in said hard carbon coating is 30/mm2 or less, and
- wherein said hard carbon coating contains at least one element selected from the group consisting of Si, B, N, P and F in a concentration of 20 atom % or less.
The optical disk as claimed in 168 wherein said hard carbon coating comprises diamond-like carbon.
A magnetic tape comprising:
- a protective film provided over said magnetic tape and comprising a hard carbon coating having a thickness of 500 Å or less,
- wherein said number of pin-holes in said hard carbon coating is 30/mm2 or less, and
- wherein said hard carbon coating contains at least one element selected from the group consisting of Si, B, N, P and F in a concentration of 20 atom % or less.
Dependencies are inferred from the claim text.