Perpendicular magnetic recording medium, method of manufacturing perpendicular magnetic recording medium, and magnetic recording apparatus

A perpendicular magnetic recording medium comprising:

• a substrate;
• a soft magnetic buffer layer formed on the substrate;
• a Ru/Ru alloy underlayer formed on the soft magnetic buffer layer, the Ru/Ru alloy underlayer including Ru or a Ru alloy;
• a recording layer formed on the Ru/Ru alloy underlayer, the recording layer including at least a layer including
• a plurality of magnetic particles having an easy axis oriented perpendicular to the substrate, and
• a non-magnetic material surrounding the plural magnetic particles;
• and
• a layered structure interposed between the soft magnetic buffer layer and the Ru/Ru alloy underlayer, the layered structure including at least
• a first Ru/Ru alloy crystalline structure film including Ru or a Ru alloy,
• a NiAl based polycrystalline film positioned directly above the first Ru/Ru alloy crystalline structure film, and
• a second Ru/Ru alloy crystalline structure film including Ru or a Ru alloy.

A method of manufacturing a perpendicular magnetic recording medium comprising the steps of:

• a) forming a layered structure including at least a Ru/Ru alloy crystalline structure film including Ru or a Ru alloy on a substrate, a first polycrystalline film including Ru or a Ru alloy, and a second polycrystalline film;
• b) forming an Ru/Ru alloy underlayer formed on the layered structure, the Ru/Ru alloy underlayer including crystal grains of Ru or Ru alloy that are spatially separated from each other by gap parts formed in the Ru/Ru alloy underlayer;
• and
• c) forming a recording layer on the Ru/Ru alloy underlayer, the recording layer including at least a layer including a plurality of magnetic particles having an easy axis oriented perpendicular to the substrate and a non-magnetic material surrounding the plural magnetic particles.

A method of manufacturing a perpendicular magnetic recording medium comprising the steps of:

• a) forming a layered structure including at least a first Ru/Ru alloy crystalline structure film including Ru or a Ru alloy, a NiAl based polycrystalline film positioned directly above the first Ru/Ru alloy crystalline structure film, and a second Ru/Ru alloy crystalline structure film including Ru or a Ru alloy;
• b) forming a Ru/Ru alloy underlayer formed on the layered structure, the Ru/Ru alloy underlayer including crystal grains of Ru or Ru alloy that are spatially separated from each other by gap parts formed in the Ru/Ru alloy underlayer;
• and
• c) forming a recording layer on the Ru/Ru alloy underlayer, the recording layer including at least a layer including a plurality of magnetic particles having an easy axis oriented perpendicular to the substrate and a non-magnetic material surrounding the plural magnetic particles.