Abstract: A multi-layer including a magnetic recording layer and a high-magnetostriction layer having a magnetostriction constant larger than that of the magnetic recording layer is formed.

Abstract: A large-capacity, low-cost, longitudinal magnetic recording medium capable of ultra-high-density recording of 70 Gigabits or more per square inch is disclosed. The longitudinal magnetic recording medium of the present invention comprises a first seed layer, a second seed layer, a first underlayer, a second underlayer, and a magnetic layer, which are formed on a nonmagnetic substrate in this order. A material containing at least Al and any one of Ru and Re is used to form the second seed layer, and a material containing at least any one of Co and Ni and one or both of Al and Ti is used to form the first underlayer. It is also possible to use Cr or a Cr alloy containing Cr and at least one element selected from the constituent element group A consisting of Ti, Mo, and W for forming the second seed layer.

Abstract: The Hr and SNR of a magnetic recording medium are increased and the signal pulse narrowed by employing a tri-layer underlayer structure containing Cr or a Cr alloy wherein the second underlayer contains Cr and B, the first underlayer preferably contains substantially pure Cr, and the third underlayer preferably contains a ternary alloy of Cr.

Abstract: A perpendicular magnetic recording medium having good perpendicular magnetic anisotropy. The magnetic recording medium includes a tantalum (Ta) seedlayer and a ruthenium (Ru) underlayer. The magnetic recording layer can be fabricated from cobalt (Co) alloys. With the Ta seedlayer, the perpendicular anisotropy and c-axis orientation of the magnetic recording layer are greatly enhanced. Unity squareness is achievable as is a negative nucleation field. The magnetic recording medium can be formed by sputtering the various layers onto a substrate. Thus, a perpendicular magnetic recording medium suitable for mass production is provided.

Abstract: A magnetic recording medium comprising; a nonmagnetic support; a first under layer which is constituted by a nonmetal element, per se, a compound consisting of nonmetal elements, or a compound containing titanium and a nonmetal element; a second under layer containing at least one element selected from the group consisting of chromium, titanium, iridium, platinum, palladium, ruthenium, rhodium, rhenium and osmium; and a magnetic layer which contains a ferromagnetic metal alloy containing at least cobalt, platinum and chromium, and a nonmagnetic compound, in this order.

Abstract: Provided is a perpendicular magnetic recording medium including a perpendicular magnetic enhancement layer having a thickness of 15 nm or greater between a substrate and a perpendicular magnetic recording layer.

Abstract: A perpendicular magnetic recording medium including a perpendicular magnetic recording layer placed over a substrate, and a multi-layered perpendicular orientation underlayer placed between the substrate and the perpendicular magnetic recording layer and having first and third underlayers each made of Pt or an alloy thereof. Due to the use of a three-layered perpendicular orientation underlayer, an excellent perpendicular orientation and a consistent crystal lattice of a Pt underlayer are obtained. Also, the perpendicular orientation underlayer has small crystal grains. Thus, the perpendicular orientation underlayer having excellent perpendicular orientation and small crystal grains enables a perpendicular magnetic recording layer to have a good thermal stability, a high recording density, and a high SNR.

Abstract: A perpendicular magnetic recording medium has a granular magnetic layer and a nonmagnetic underlayer of a metal or an alloy having a hexagonal close packed (hcp) crystal structure. A seed layer of a metal or an alloy of a face-centered cubic (fcc) crystal structure is provided under the nonmagnetic underlayer. Such a perpendicular magnetic recording medium exhibits excellent magnetic characteristics even when the thickness of the underlayer or the total thickness of the underlayer and the seed layer is very thin. Excellent magnetic characteristics can be obtained even when of the substrate is not preheated. Accordingly, a nonmagnetic substrate, such as a plastic resin can be employed to reduce the manufacturing cost.