Abstract: Embodiments of the present invention provide a magnetic disk drive capable of allowing higher data transfer rates and higher recording densities. According to one embodiment, an upper magnetic core and lower magnetic core comprise a multi-layered magnetic film formed by alternately stacking a face-centered cubic (fcc) crystalline magnetic thin layer and a body-centered cubic (bcc) crystalline magnetic thin layer by plating. The plating bath is such that the temperature is about 30±1° C., pH is about 2.0?1.0 to 2.0+0.5, metal ion concentrations are about 5 to 25 (g/l) for Ni2+ and 5 to 15 (g/l) for Fe2+, saccharin sodium concentration is about 1.5±1.0 (g/l), sodium chloride concentration is about 25±5 (g/l), and boric acid concentration is about 25±5 (g/l). Since each layer's crystal structure is different from that of its adjacent lower layer, epitaxial growth is broken within each layer.

Abstract: Embodiments of the present invention provide a magnetic disk drive with an enclosure that prevents the low-density gas from leaking out owing to reduction of shrinkage cavities near tapped holes. According to one embodiment of the present invention, an aluminum alloy is forced into the region of the base in which the tapped hole is to be made, by squeezing in the final stage of die casting to form the base. This procedure increases the density of aluminum alloy above 2.7 g/cm3, and the densified aluminum alloy in the region for tapped holes, is free of shrinkage cavities that can cause gas leakage.

Abstract: Embodiments in accordance with the present invention enable a disk drive of an address system to write data normally, wherein track groups of different track widths are discretely disposed on the storage medium in a same disk drive and the dimensional relationship among physical block addresses of a sector is valid for the dimensional relationship among logical block addresses. Track groups are managed corresponding to their respective track width in a disk drive and for disposing successively in a logical block address space the respective track groups located discretely on the physical block address space.

Abstract: The present invention relates to a method for producing a transducer slider. The method involves first coating a substrate with a radiation-sensitive layer and exposing the radiation-sensitive layer to radiation according to an intensity pattern. Preferably, the intensity pattern is provided using a grayscale mask. Once the image is developed into the radiation-sensitive layer, the image is transferred into the substrate to form a transducer slider having a surface profile comprising a tapered edge. In the alternative or in addition, the surface profile may comprise a rounded corner. The invention also relates to a structure for forming a transducer slider.

Abstract: An improved disk drive system that employs a lubricant with improved charge control is provided. The disk drive system is comprised of a rotatably mounted magnetic disk. A rotor is coupled to the disk and rotatably retained by a stator. A bearing is formed that serves as an interface between the stator and the rotor. A motor coupled to the rotor rotates the magnetic disk via the rotor. Located in the bearing is a lubricant having a low relative electrical permittivity.

Abstract: The invention relates generally to the bonding of one or more sliders in styrene and butadiene polymers. More particularly, the invention relates to planarized slider assemblies formed by using debondable solid encapsulants comprised of styrene and butadiene polymers. The invention also relates to methods that use such encapsulants in conjunction with resists to produce magnetic head sliders having patterned air-bearing surfaces.

Abstract: A slider assembly is provided comprising a plurality of sliders bonded by a debondable solid encapsulant comprised of different first and second polymers The solid encapsulant is comprised of a polymer prepared by polymerizing an encapsulant fluid comprising a homogeneous mixture of first and second constituents. The first constituent is comprised of a first monomer suitable for in situ polymerization to form the first polymer. The second constituent is comprised of the second polymer or a second monomer suitable for in situ polymerization to form the second polymer. The first constituent does not substantially react with the second constituent. Each slider has a surface that is free from the encapsulant. The encapsulant-free surfaces are coplanar to each other. Also provided are methods for forming the assembly and methods for patterning a slider surface using the encapsulant.

Abstract: A system for selectively sensing and removing asperities from hard disk drive disk is disclosed. The system includes a test stand supporting the disk, the test stand having at least one suspension for flying over a surface of the disk. The system also includes a glide pad coupled to the at least one suspension for flying over the surface and locating asperities. A PZT sensor is coupled to the glide pad for sensing and mapping asperities on the surface of the disk. A burnish pad is coupled to the at least one suspension for wearing-away sensed and mapped asperities on the surface of the disk and a thermal fly height controller is coupled to the burnish pad for protruding the burnish pad when it is proximate to one of the mapped asperities for facilitating the wearing-away of the mapped asperity.

Abstract: A method for selectively sensing and removing asperities from the surface of hard disk drive media is disclosed. A thermally controlled flying height burnish slider is flown on a test stand with its thermal flying height control deactivated. The burnish slider flies at a nominal flying height over the surface of the media to remove any existing loose particles from the surface. A glide slider coupled to a PZT sensor is then flown over the surface of the media, the PZT sensor head mapping locations of any asperities on the surface of the media. The thermal flying height controlled burnish slider is next flown over the surface of the media with the thermal flying height control activated. The thermal flying height control is actuated when a mapped location of an asperity on the surface is proximate to the burnish slider, causing the burnish slider to protrude, wearing off the asperity.

Abstract: A slider assembly is provided comprising a plurality of sliders bonded by a debondable solid encapsulant. The solid encapsulant is comprised of a polymer prepared by polymerizing a mixture of first and second monomers in a nonstoichiometric ratio effective to render the encapsulant debondable. Each slider has a surface that is free from the encapsulant. The encapsulant-free surfaces are coplanar to each other. Also provided are methods for forming the assembly and methods for patterning a slider surface using the encapsulant.

Abstract: The invention relates generally to the bonding of one or more sliders in styrene and acrylate polymers. More particularly, the invention relates to planarized slider assemblies formed by using debondable solid encapsulants comprised of styrene and acrylate polymers. The invention also relates to methods that use such encapsulants in conjunction with resists to produce magnetic head sliders having patterned air-bearing surfaces.

Abstract: An electrical potential difference between a slider body and a hard disk of a hard disk drive is eliminated based on the flying-height spacing of the slider body between the slider body and the hard disk. A predetermined bias voltage is applied between the slider body and the hard disk that includes a DC component and an AC component and that is based on the detected flying-height spacing of the slider body. The flying-height spacing can be detected based a minimum slider-to-disk clearance change from a design flying height of the slider at a frequency of the AC component as the DC component of the predetermined bias voltage is varied. Alternatively, the flying-height spacing can be detected based on a minimum electrodynamic response of the slider to a first harmonic of the AC frequency of the AC component as the DC component is varied.