Digital Equipment Corporation

Quantum Corporation

Alan Lee Sidman

Michael Mallary

Michelle Martin

Harold B. Shukovsky

Michael L. Mallary

Michael L Mallary

Harold B Shukovsky

Sharat Batra

Shyam C Das

Kazuo Ishibashi

Hiroshi Sato

Takahiro Mori

Richard A Stander

Seshadri Ramaswamy

Peter T Griffin

Keith R Hussinger

A method and apparatus for increasing recording density in zone bit recording on a magnetic recording disk without increasing track density by maximizing the data density the at disk's outer track. A magnetic recording head is attached to a parallelogram shaped slider such that the head's gap-to-radius skew and the slider rail skew changes continuously as the slider moves in an arcuate path from the disk's inner track to the disk's outer track. The parallelogram slider is designed to reduce the loss of data density at the outer track by minimizing the head's gap-to-radius skew while maximizing the rail skew angle at the outer track to maintain an essentially constant low fly height across the disk.

Method and apparatus for increasing data density in magnetic data

A magnetoresistive ('MR') sensor constructed with a concave shaped edge in order to provide an effective longitudinal bias field in the center of the active MR element sufficient to obviate multi-domain states and concomitant Barkhausen noise. Utilizing the concave shape proposed herein, the 'stripe height' of the element is at a minimum in the center of the active region and increases toward the off-track boundary. In a preferred embodiment, a substantially constant effective longitudinal bias field may be obtained throughout the active MR element if the stripe height increases as an exponential function of the square of the off-track distance. The principles of the present invention are likewise applicable to use in spin valve ('SV') and other giant magnetoresistive ('GMR') sensors.

Longitudinally biased magnetoresistive sensor having a concave shaped

The magnetic medium includes a magnetic under image layer which may be separated from the hard magnetic recording layer by a nonmagnetic buffer layer. Virtual magnetic images induced in the magnetic image layer reduce off-track magnetization seen by the recording head. Thus, interference caused by tracks adjacent to the track being read is reduced.

Method of making a magnetic medium for longitudinal recording

A thin film magnetic transducer formed in multiple layers and comprising a yoke having a plurality of arms, at least one of which has segments lying in separate layers and connected through a transition layer, and a multiturn coil intertwined with the yoke to provide at least two flux interactions between the yoke and coil. The transducer is constructed to enhance flux conduction by rotation and minimize flux conduction by wall motion in the yoke.

Method of making a transducer with improved inductive coupling

A thin film magnetic transducer is formed in a plurality of layers and comprises a yoke with at least one arm having segments respectively lying in separate said layers and connected through a transition layer, and one or more coils; the coil (or coils) and the yoke are intertwined to provide more than two flux interactions therebetween. In one aspect, the segments of the arm are oriented obliquely to each other and have easy axes of magnetization respectively transverse to the directions of flux conduction through said segments, and the segments are joined together so that flux can pass between them without flowing parallel to the easy axis of any of the segments.

A thin film magnetic recording head for high-density recording applications. The head includes a pole formed from at least two ferromagnetic material layers with one layer having high anisotropy (H.sub.k) and low permeability (.mu.), and the other layer having low H.sub.k and high .mu.. The high H.sub.k layer provides the lower magnetic impedance flux path in the tip region and the low H.sub.k layer provides the lower magnetic impedance path in the yoke region of the head. A non-magnetic film may be disposed between the layers, with a thickness chosen to minimize domain flux coupling of the two magnetic layers, while allowing magnetic signal flux transfer between layers at an appropriate point between the tip and the yoke. The pole may be sculpted so that the low H.sub.k layer extends only partially into the tip region, or so that the high H.sub.k layer extends only partially into the yoke. Alternatively, the invention may use a laminated, high permeability layer and a homogeneous layer in place of the high H.sub.k and low H.sub.k layers.

Process for fabricating magnetic film recording head for use with a

The present invention pertains to a thin film magnetic recording head which minimizes erase fringing and the process for manufacturing the thin film magnetic recording head. The head is used to record and read information made up of alternating magnetization patterns on a magnetic recording medium. Known recording heads cause erase fringing of the magnetic medium during the write operations. The structure of the recording head of the present invention has the ABS portion of one of two magnetic poles beveled away from ABS at the gap to zero throat, reduces erase fringing of the magnetic recording medium and is easily manufactured. By reducing erase fringing, the present invention enables an increase in disk density of information without risking loss of data integrity.

Thin film read/write head for minimizing erase fringing and method of

A disk drive (10) includes a head positioner (16) on which are mounted separate read and write heads (52 and 54) that are spaced apart in the direction radial of the disk axis. Headers (50) on a disk (12) in the disk drive (10) establish track pitches that vary with radial position in such a manner that the radial separation of the read and write heads (52, 54) is equal to an integral number of track spacings that is substantially independent of the positioner angle.

Side-by-side read/write heads with rotary positioner

An apparatus for providing radial uniaxial anisotropy in the soft magnetic layer of a magnetic recording disk is disclosed. While the soft magnetic layer is being deposited on the recording disk, the magnetic field. The alternating perpendicular magnetic field causes eddy currents to flow in the disk, in a circumferential direction. The eddy currents, in turn cause a magnetic field in a radial direction, thereby resulting in the desired radial uniaxial anisotropy.

Apparatus for providing uniaxial anisotropy in a magnetic recording disk

A thin film magnetic transducer includes a yoke having a plurality of arms and a plurality of coils, at least one of which is intertwined with the yoke to provide multiple flux interactions therebetween. Each arm includes a plurality of elongated segments that are oriented obliquely to each other and have easy axes of magnetization respectively transverse to the directions of flux conduction through the segments, and the segments (and arms) are joined together to cause flux to pass between them without flowing parallel to the easy axes.

Tranducer with improved inductive coupling

Magnetic medium for longitudinal recording

Magnetic pole configuration for high density thin film recording head

A method and apparatus for providing radial uniaxial anisotropy in the soft magnetic layer of a magnetic recording disk is disclosed. While the soft magnetic layer is being deposited on the recording disk, the magnetic field. The alternating perpendicular magnetic field causes eddy currents to flow in the disk, in a circumferential direction. The eddy currents, in turn cause a magnetic field in a radial direction, thereby resulting in the desired radial uniaxial anisotropy.

Method for providing uniaxial anisotropy in magnetic recording disks

A thin-film head architecture is provided that incorporates an asymmetrical arrangement of poles along a defined area of the head extending from the pole tips to a flux via in the yoke region. The flux conducts vertically by small-angle rotations within the defined area of the head during read operations, thereby obviating the need for horizontal conduction by domain wall motion.

Architecture for a thin-film magnetic recording head

A magnetic recording head including a read pole disposed in a gap between a pair of write poles, and a sensor spaced away from the gap, the read pole adapted to conduct flux to the sensor, each write pole forming a respective cavity between itself and the read pole where the outside of at least one pole is tapered down toward the pole tip, the poles being closer together at their tips than they are near the sensor.

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Berlin, MA, United States of America

Michael L Mallary