Magnetic recording medium and magnetic recording apparatus
AssigneeKabushiki Kaisha Toshiba
InventorsTomoyuki Maeda, Akira Kikitsu, Soichi Oikawa, Takeshi Iwasaki
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Abstract
A large grain diameter under-layer of at least one selected from Cu, Ni or Rh, comprising large average diameter crystalline grains of 50 nm or more than 50 nm with the (100) crystal plane of the grains oriented parallel to the substrate surface, was formed on a substrate. Then, a magnetic recording layer was deposited on the under-layer. The magnetic recording medium carrying this structure showed very small magnetic crystalline grains in magnetic layer, and excellent overwrite characteristics and signal to noise ratio at high recording density.
Claims16
A magnetic recording medium, comprising:
- a substrate;
- a large grain diameter under-layer formed on the substrate;
- a magnetic recording layer on the under-layer;
- and
- a protecting layer formed on the magnetic recording layer;
- wherein the large grain diameter under-layer comprises crystalline grains of at least one selected from the group consisting essentially of Cu, Ni, Rh and Pt, having average grain diameter dc larger than or equal to 50 nm, and orienting (100) planes of the grains parallel to the substrate surface.
A magnetic recording and reproducing apparatus, comprising:
- a magnetic recording medium, comprising:
- a substrate, a large grain diameter under-layer formed on the substrate, and a magnetic recording layer on the under-layer;
- and
- a protecting layer formed on the magnetic recording layer;
- wherein the large grain diameter under-layer comprising crystalline grains of at least one selected from the group consisting essentially of Cu, Ni, Rh and Pt, having average grain diameter dc of larger than or equal to 50 nm, and orienting (100) planes of the grains parallel to the substrate surface;
- a recording medium driving mechanism, driving the magnetic recording medium;
- a recording and reproducing head mechanism, recording information to the magnetic recording medium and reproducing from the magnetic recording medium;
- a head driving mechanism, driving the recording and reproducing head;
- and
- a recording and reproducing signal processing system, processing recording signals and reproducing signals.
Dependencies are inferred from the claim text.