Digital Equipment Corporation

Quantum Corporation

Maxtor Corporation

Mke-quantum Components Colorado, LLC

Michael I Mallary

Harold B Shukovsky

Alan L Sidman

Michelle Martin

Karl A Frey

Kofi Gyasi

Ara Patapoutian

Michael D Leis

Steven E Lambert

Alan B Smith

Sreekanth Venkatesan

Shu-Huei Liu

Christine Bisagni

An apparatus and method for increasing the data storage capacity of a data storage devicehaving media surfaces. One or more of a linear density of data, a track density of data, or an error code level of data, is selected for a portionof a media surface. Data is recorded on the portionof the media surfaceat the selected linear density, track density, or error code level. Thereafter, the recorded data is read and an error rate of the recorded data is derived, directly or indirectly. The derived error rate is compared to an acceptable error rate, and if the derived error rate is greater than the acceptable error rate, the previous steps are repeated for another linear density, track density, or error code level, until the derived error rate is less than or equal to the acceptable error rate, to provide a recordable linear density, track density, or error code level of data for the media surface

Method and apparatus for selecting storage capacity of data storage media

An optical positioning circuit includes an electro-optic positioner which positions an optical beam on an optical medium to read/write patterns of data on the optical medium, and a driver circuit, such as an inductive capacitive circuit, which drives the electro-optic positioner. The optical medium has a dimension along which the optical medium is moved, and each of the micropatterns extends along less than (e.g., {fraction (1/10)}th of) that dimension.

Scanning micropatterns on an optical medium

A flying optical head assembly for a magneto-optical data storage device includes a slider body mounting an optical element having a narrowed optical aperture extending through a location of the slider body, a recessed region surrounding the location passing the optical aperture, a magnetic pole sheet layer for heat dissipation and reduced magnetic reluctance formed in the recessed region and having an insulation layer and an opening for the optical aperture, and a magnetic bias coil formed on the insulation layer and surrounding the narrowed optical aperture. When formed of electrically conductive material, the sheet layer includes at least one radial slot for preventing a single turn short circuit in direct proximity to the coil. Multiple slots are preferred for bonding and to reduce eddy currents.

Field enhancing magnetic pole for magneto-optical recording and reproducing device

A suspension assembly that supports a head adjacent to a rotating storage disk is provided for use within a single or multi-platter disk drive. The suspension assembly includes a generally elongated loadbeam that has an electrically grounded baseplate at a first end thereof and a gimbaled flexure portion for supporting the head over the rotating storage disk at a second end thereof. A power conductor electrically interconnected between a power source and the loadbeam enables the power source to heat a predetermined portion of the loadbeam to adjust the gramload of the suspension assembly for controlling the fly height of the head.

Suspension assembly with adjustable gramload

An objective-solid immersion lens assembly includes a unitary solid immersion lens body having an optical axis, an evanescent wave-conducting region along the optical axis, and a substantially spherical surface portion surrounding the optical axis oppositely the wave emitting region. A discrete objective lens is attached to, or otherwise formned at, the solid immersion lens body at the substantially spherical surface portion to be in alignment with the optical axis. Several manufacturing methods for making an air bearing slider including the objective-solid immersion lens assembly are disclosed.

Integrated objective/solid immersion lens for near field recording

A disk configured to store magnetically readable data is comprised of three distinct annular regions: a parking zone, a take-off zone, and a data storage area. The parking zone is heavily textured or roughened on the order of about 1 microinch, but the take-off zone is only lightly textured or roughened. A transducer head is located over the parking zone when the rotational speed of the disk is relatively slow. Once the rotational speed increases above this minimal value, the transducing head is moved to the take-off zone until the speed of the disk approaches the desired operating speed.

Magnetic disk having separate park and take-off zones

The pole pieces of a thin film head are formed by two thin film layers of the magnetic metal NiFe, each NiFe layer being about 20,000 angstroms thick. These two NiFe layers are separated by an electrically insulating layer of alumina (Al.sub.2 O.sub.3), ceramic or NiFe oxide that is about 100 angstroms thick. In one embodiment, a hard-baked photoresist layer is formed only around the edges of the first NiFe layer, the electrically insulating layer is deposited over the top surface of the first NiFe layer and over the hard-baked photoresist layer, and the second NiFe layer is then deposited, thus providing a three-layer metal/insulator/metal pole piece wherein the hard baked photoresist blocks edge short circuiting between the two thin film NiFe layers. In another embodiment, edge short circuiting is minimized by allowing a small filament(s) of a high electrical resistance plating seed layer of NiFe to extend between the two NiFe thin film layers, the high resistance of these long and thin NiFe filaments being much greater than the resistance of the two NiFe thin film layers.

Laminated plated pole pieces for thin film magnetic transducers

A process resulting in enhanced pole performance, relative to permalloy poles, in narrow track magnetic devices. A preferred process includes increasing the anisotropy field of the pole material while maintaining an acceptable coercivity level and near zero magnetostriction. One embodiment utilizes a NiCoFe alloy containing 22% cobalt by weight, heat treated in an easy axis magnetic field in a non-oxidizing atmosphere. This process achieves favorable domain structures at narrow pole tip widths.

Magnetic devices with enhanced poles

In a magnetic write head, the top pole piece reduces in width and cross-sectional area in a number of steps by providing a first wide tapered zone whose width progressively decreases at a first rate that is determined by side surfaces that are inclined at an angle of about 45 to 55-degrees, and providing a second narrow tapered zone whose width progressively decreases at a second lower rate that is determined by side surfaces that are inclined at an angle of about 5-degrees. This second narrow tapered zone may comprise the serial arrangement of three individual zones, a first of which whose width decreases at a rate that is determined by side that are inclined at about 4.7-degrees, a second of which whose width decreases at a rate that is determined by side that are inclined at about 5.7-degrees, and third of which whose width decreases at a rate that is determined by sides that are inclined at about 6.8-degrees. The pole piece's tapered zone terminates in a narrow and constant width pole tip. As a result, a long magnetic flux saturation zone is provided, wherein length is measured in a direction that extends toward the head's pole tip or write gap. A gap field versus write current (Bg-vs-Iw) curve is thereby provided having a high magnitude Bg and nearly flat slope Bg saturation region. The head is driven with an excess magnitude Iw, thus causing the head's Bg to increase rapidly to its optimum high magnitude, whereupon the increase in Bg abruptly stops. Better overwrite (OVW) is provided, less non linear transition shift (NLTS) occurs, and narrower read-back pulses are provided, at both the inner diameter (ID) and outer diameter (OD) of an associated magnetic recording disk.

Long saturation zone magnetic write head

Process of forming magnetic devices with enhanced poles

One aspect of the present invention relates to enabling rotational flux conduction through magnetic film devices by creating a magnetic film layer with anisotropy perpendicular to the plane of the film layer, the film deposited in sufficient thickness so that there is a rest state rotational conduction path in the plane of the film layer. Another aspect of the invention is to provide for flux spreading in a magnetic device having perpendicular anisotropy. One feature of the present invention enables forming perpendicularly oriented central domains in a magnetic device so that the path for conduction of signal flux by rotation remains open even for very narrow signal flux paths. Another feature of the invention is to orient at rest domain states of a magnetic device pole (or poles) perpendicular to two desired in-plane rotational flux travel directions. Another feature of the invention is to orient edge domains in this type of magnetic device into a plane where their relative widths do not impact substantially on rotational flux flow through the device for narrow track heads. A preferred embodiment of the present invention includes at least one pole of a magnetic device, formed on a substrate, having a preferred at rest pole domain orientation perpendicular to the substrate plane.

Perpendicular anisotropy in thin film devices

A thin film two-pole inductive magnetic head for a computer disk drive assembly. The head comprises a substrate, a first pole formed over the substrate, a gap layer formed over the first pole and a second pole formed over the gap layer. The first and second poles have their distal ends coupled together in a yoke region, while their proximal ends terminate at their tips in an air bearing surface. A leading surface of the first pole extends back toward the yoke region at an acute angle to the air bearing surface. The head reduces the amplitude and high frequency content of secondary pulses in a readback waveform so as to ease the task of electronically isolating the main pulses for downstream processing of the read data.

Thin film two-pole inductive magnetic head with minimized secondary

The head includes a read pole disposed between a pair of write poles spaced apart to form a gap therebetween. The read pole conducts flux to a flux sensor that is located away from the gap. The head can be utilized for both longitudinal and perpendicular recording and the readback function can be carried out by an inductive coil or flux sensing devices such as a Hall sensor or an MR sensor. The recording head achieves high readback resolution, high write field gradients, and the capability for write wide read narrow. The read pole and write poles are laminated structures.

Three-pole magnetic recording head with high readback resolution

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 the 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 the 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.

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Berlin, MA, United States of America

Michael I Mallary