Abstract: High areal storage density, patterned magnetic media comprising a patterned plurality of at least partially crystalline, ferromagnetic particles or grains are provided by means of a simple, economical process wherein a non-magnetic substrate is provided with a layer of an amorphous, paramagnetic or anti-paramagnetic material comprising at least one component, e.g., a metal element, which is ferromagnetic when in at least partially crystalline form, and at least partially crystallizing the at least one component at selected areas of the amorphous layer to form a spaced-apart pattern of at least partially crystallized, ferromagnetic particles or grains of the at least one component, the particles or grains being spaced apart and surrounded by a matrix of the amorphous material. Embodiments include utilizing a focussed or scanned laser source and an amorphous Ni—P layer for forming ferromagnetic Ni particles or grains.

Abstract: Abnormal nodule formation during electroless plating, e.g., of amorphous NiP “seed” layers utilized in the manufacture of magnetic recording media, is eliminated or substantially reduced by performing the electroless plating process in an apparatus employing polymeric or polymer-based materials which are substantially resistant to degradation upon prolonged contact with the electroless plating bath at an elevated temperature, i.e., release of soluble, low molecular weight, carbon-containing species which are incorporated in the electroless plating deposit and act as nucleation centers for abnormal growth leading to nodule formation. Suitable degradation-resistant polymeric materials for use as fittings, piping, racks, tanks, etc. of the electroless plating apparatus include fluorine-containing hydrocarbons and fluorocarbons.

Abstract: High areal density magnetic recording media exhibiting low noise are formed with a Ni—P—X plating layer, in which X is an additive meeting the following requirement: (1) The additive has a higher oxidation potential than that of Ni so that grains of an additive-rich-oxide will form first during oxidation under a controlled atmosphere and grains of a Ni-rich-oxide, if any, will form subsequently and separately from the grains of the additive-rich oxide. (2) The additive has a tendency to segregate to the top surface. (3) The additive is not a catalyst poison for Ni—P plating in the composition range.

Abstract: High areal storage density, patterned magnetic media comprising a patterned plurality of at least partially crystalline, ferromagnetic particles or grains are provided by means of a simple, economical process wherein a non-magnetic substrate is provided with a layer of an amorphous, paramagnetic or anti-paramagnetic material comprising at least one component, e.g., a metal element, which is ferromagnetic when in at least partially crystalline form, and at least partially crystallizing the at least one component at selected areas of the amorphous layer to form a spaced-apart pattern of at least partially crystallized, ferromagnetic particles or grains of the at least one component, the particles or grains being spaced apart and surrounded by a matrix of the amorphous material. Embodiments include utilizing a focussed or scanned laser source and an amorphous Ni—P layer for forming ferromagnetic Ni particles or grains.