Seagate Technology Incorporated

Control Data Corporation

Magnetic Peripherals Inc.

Richard A Strom

Robert E Chapin

Mohamed-Salah Houceine Khlif

Peter Crane

William N Mayer

Gordon Merle Jones

Paul F Michalek

Robert Wallace Johnson

Clark Bergman

An apparatus for adjusting twist curvature of a slider is provided, wherein the slider has a bearing surface, a back surface, which is opposite to the bearing surface, a longitudinal axis and a transverse axis. The apparatus includes a light source adapted to produce a light beam capable of altering material stresses in a working surface of the slider. The apparatus further includes an apparatus for obtaining a measure of the twist curvature of the bearing surface and for scanning the light beam across the working surface in a pattern selected to alter material stresses in the working surface asymmetrically with respect to the longitudinal axis and the transverse axis based on the measure of the twist curvature so as to induce a change in the twist curvature.

Apparatus for controlling twist curvature of a disc head slider

An apparatus and method for controlling twist curvature of a disc head slider is provided, where the slider has a bearing surface, a back surface, which is opposite to the bearing surface, a longitudinal axis and a transverse axis. The apparatus obtains a measure of the twist curvature of the bearing surface and selectively alters material stresses in a working surface of the slider. The material stresses are altered asymmetrically with respect to the longitudinal axis and the transverse axis based on the measure of the twist curvature to induce a change in the twist curvature.

Method for controlling twist curvature of a disc head slider

A method for laser edge treating (LET) a slider and a slider with laser edge treatment, wherein the laser treatment is used to modify the curvature along the air-bearing surface, including altering a slider edge ridge that forms at the edges of the air bearing surface due to compressive stresses induced in the air bearing surface by a prior lapping step. The laser makes positive and negative adjustments to crown, cross curve, and twist as measured on the air bearing surface by selectively altering the treatment pattern or the treatment location on the slider's side edges.

Laser edge treatment of sliders

A method of controlling curvature of a disc head slider having a slider body with a bearing surface, a back surface, which is opposite to the bearing surface, a first axis and a second axis, which is perpendicular to the first axis, is provided. The method includes directing a continuous-wave laser beam toward the back surface to form a laser spot on the back surface. The laser spot is scanned along the back surface in a direction parallel to the first axis or the second axis to form a continuous elongated scan line on the back surface such that the back surface melts and then cools along the scan line to induce anisotropic tensile stress in the back surface, which is oriented predominately parallel to the scan line.

Slider having thermally applied tensile stress for curvature control and method of applying tensile stress

A process of dicing a bar to form a plurality of sliders having air bearing surfaces commences with defining a dice lane having a nominal surface between adjacent slider portions on the bar, opposite edges of the dice lane defining respective edge surfaces of adjacent slider portions. The dice lane is cut away with a blade to form an edge surface of the slider. A barrier trench is formed in the nominal surface along each edge of the dice lane. The barrier trench has a width that extends a predetermined distance into the slider portion of the bar from the edge of the dice lane and a predetermined depth to eliminate ridges in the air bearing surface of the slider. The barrier trench is formed either before or after the dicing of the slider. The slider thus formed is characterized by an absence of ridges in the air bearing surface.

Process of eliminating ridges formed during dicing of aerodynamic sliders, and sliders formed thereby

A method of controlling curvature of hydrodynamic bearing slider. The method includes adding a preselected amount of compressive surface stress to the slider to change curvature of the slider and then removing a portion of the added compressive stress to adjust the curvature.

Compressive stress treatment method for controlling curvature of a hydrodynamic bearing slider

Compressive stress treatment method for controlling curvature of a

A lapping apparatus for controlling curvature of a hydrodynamic bearing slider includes a bar of slider substrate material and a lapping carrier. The bar of slider substrate material includes at least one slider body having a bearing surface, and a back surface, with the back surface having a periphery and a center. The lapping carrier has a support surface which supports the slider back surface at the periphery and has a recess in the support surface adjacent the slider center such that the back surface is unsupported at the slider center. During the lapping process, the center of the slider deflects into the recess in the lapping carrier such that less material is lapped from the bearing surface at the center than at the periphery, which results in a positive curvature change in the bearing surface.

Deflection lapping apparatus and method for hydrodynamic bearing slider

A method of controlling curvature of a disc head slider having a slider body with a bearing surface and a back surface, which is opposite to the bearing surface. The method includes melting and then cooling the back surface to add tensile stress to the back surface which induces curvature of the bearing surface.

Slider having thermally applied tensile stress for curvature control and

A negative pressure air-bearing slider comprises a slider body having a surface with a leading edge, a trailing edge and first and second side edges. First and second raised side rails are positioned along cross rail extends between the first and second raised side rails. The raised cross rail has a leading edge and a trailing edge. A negative pressure cavity extends from the raised cross rail toward the trailing edge and between the side rails. A choke is positioned within the raised cross rail, which widens from the leading edge of the raised cross rail toward the trailing edge of the raised cross rail.

Negative pressure air bearing slider with a choke for restricting air

A negative pressure air-bearing slider includes a slider body having a surface with a leading edge, a trailing edge and first and second side edges. First and second raised side rails are positioned along the first and second side edges, respectively. A raised crossed rail extends between the side rails. A negative pressure cavity extends from the cross rail to the trailing edge and is positioned between the side rails. A first isolation channel is disposed between the negative pressure cavity and the first side rail. A second isolation channel is disposed between the negative pressure cavity and the second side rail. The first and second isolation channels converge together toward the leading edge and communicate with the leading edge.

Negative pressure air bearing slider having converging isolation channels

A negative pressure air bearing slider comprises a slider body having a surface with a leading edge, a trailing edge and first and second side edges. First and second raised side rails are positioned along the first and second side edges, respectively. The side rails each form an air bearing surface with an inside and an outside edge extending between the leading edge and the trailing edge. A raised cross rail is positioned near the leading edge and extends between the side rails. A negative pressure cavity is positioned between the side rails, trailing the cross rail. A first isolation channel is disposed between the first side rail and the negative pressure cavity. A second isolation channel is disposed between the second side rail and the negative pressure cavity. Intermediate surfaces extend along only a portion of the inside edges of the airbearing surfaces formed by the first and second side rails. The intermediate surfaces are recessed from the air bearing surfaces and are raised from the isolation channels.

Negative pressure air bearing slider having isolation channels with edge

A negative pressure air-bearing slider includes a slider body having a surface with a leading edge, a trailing edge, first and second side edges and a longitudinal axis extending from the leading edge to the trailing edge. First and second side rails are positioned along the first and second side edges, respectively. A raised crossed rail extends between the side rails and has a leading edge and a trailing edge. A negative pressure cavity extends from the cross rail toward the trailing edge of the slider body and between the side rails. A pair of angled channels formed in the cross rail permit relatively more air to enter the negative pressure cavity when the slider flies with its longitudinal axis at skew with respect to air flow than when the slider flies with its longitudinal axis in parallel with respect to air flow.

Negative pressure air bearing slider with spoiler channels

A negative pressure air-bearing slider supports a transducer proximate a rotating disc. The slider includes a slider body having a surface with a leading edge, a trailing edge, and a first and second side edges. First and second raised side rails are positioned along the first and second side edges, respectively. A raised cross rail is positioned near the leading edge and extends between the side rails. A negative pressure cavity trails the cross rail and is positioned between the side rails. The negative pressure cavity develops subambient pressure during flight. A raised island forms an air-bearing surface positioned at the trailing edge and between the side rails. The island has a forward edge which is raised from the negative pressure cavity and is recessed from the air-bearing surface to increase pressurization of the air-bearing surface. The air-bearing surface increases lift and slider flying height at the trailing edge at low disc speeds. At high disc speeds, the air-bearing surface has a diminished effect relative to an increased subambient pressure effect of the negative pressure cavity which provides a more even flying height over inner and outer data tracks on the disc surface.

Negative pressure air bearing slider having an air bearing surface

A negative pressure air-bearing slider comprises a slider body having a surface with a leading edge, a trailing edge and first and second side edges. First and second side rails are positioned along the first and second side edges, respectively. The side rails each form an air-bearing surface which develops positive pressure during flight. A raised crossed rail is positioned near the leading edge and extends between the side rails. A negative pressure cavity trails the cross rail and is positioned between the side rails. A first isolation channel and a first isolation separating rail are positioned between the first side rail and the negative pressure cavity. A second isolation channel and a second isolation separating rail are positioned between the second side rail and the negative pressure cavity. The isolation channels and the isolation separating rails terminate prior to the trailing edge of the slider.

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Eagan, MN, United States of America

Richard A Strom