International Business Machines Corporation

Huizong Lu

Ali Reza Taheri

Pieter J Kerstens

Michael G Lisanke

Lanphuong Thi Pena

Andrew Ching Tam

Peter Michael Baumgart

Michael Barenboim

Hong S Seing

Eric V Schnetzer

Peter P Chrusch

Benny Michael Harper

Alan David Dorundo

Benjamin Karni

Kenneth Wayne Watts

Iraj Kahkesh Pour

Hee Kuwon Park

Darell Smith Whitaker

Samuel Sheung-Lok So

Akram Aref Bou-Ghannam

Richard J McCormick

Benjamin Kami

A disk texturing tool is used, for example, to provide textured spots in an annular portion of both sides of a hardfile disk. An optical system includes a laser directed at a beamsplitter to split the laser beam into two beams having approximately equal power, which are directed along parallel paths through a power control optics block to expose simultaneously opposite sides of a disk to be textured. A visible laser beam is also directed along this optical system to an inspection spot on each side of the disk, by which a central portion of each textured spots passes. A beam angle detector detects deflection of a reflection of the inspection beam from this spot in the direction of motion of the disk at this spot. This deflection provides a measure of the topography of the spot.

Optical apparatus for monitoring profiles of textured spots during a

A device is provided for determining the height and/or tilt of local features on the surface of a sample. The device includes a laser projecting a collimated beam at an oblique angle at a reflection point on the sample surface and a converging lens having an optical axis extending at an angle of reflection equal to the angle of incidence from the reflection point. The focusing characteristics of the lens are used to separate the deflection of the reflected collimated beam due to tilt of the surface from such deflection due to linear displacement of the surface.

Optical apparatus for determining the height and tilt of a sample surface

Apparatus for inspecting the surface of a sample includes a wide scanning interferometer, which is used to locate defects, or anomalies in the surface, and a narrow scanning interferometer, which is used to develop profiles of individual defects found by the narrow scanning interferometer. The sample may be driven in rotation about an axis, while the interferometers are independently moved radially to the axis.

Optical apparatus for rapid defect analysis

Optical apparatus is provided for inspecting a textured surface measures a level of scattered reflections from the surface, occurring when an inspection laser beam is directed at the surface. In a first version of the apparatus, the intensity of scattered reflections directed at a single light-sensitive element are compared with the intensity of specular reflections directed at another light-sensitive element. In a second version, diffraction rings formed by the scattered reflections are passed through a mask which attenuates their intensity according to differences between the actual diffraction rings and a predetermined diffraction pattern. In a third version, the scattered light is divided by a beamsplitter to pass through one mask which increases attenuation as the diffraction rings are increased in size compared to a predetermined diffraction pattern or through another mask which decreases attenuation as the diffraction rings are decreased in size compared to the predetermined diffraction pattern.

Textured surface monitoring and control apparatus

A disk texturing process uses a single pulsed laser to texture disks within a first group, which are carried through the texturing process on a first spindle assembly, and from a second group, which are carried through the texturing process on a second spindle assembly. Preferably, disks from the first group are textured alternately with disks in the second group. A first level of least one texturing parameter is stored for use only as the process is applied to disks from the first group, while a second level of the same texturing parameter is stored for use only as the process is applied to disks from the second group. These levels may be derived from measurements of textured spots made with interferometric devices forming portions of a texturing station.

Laser texturing apparatus with dual laser paths having an independently

An interferometer forms a pair of projected sub-beams by decomposing a single coherent, linearly-polarized beam. These sub-beams are focussed by an objective lens onto a pair of test spots on a test surface. The reflections of these sub-beams are recombined to form an elliptically polarized return beam, which is broken into return sub-beams of opposing polarities in a polarizing beam splitter. The intensities of these return sub-beams are used to calculate a difference in height between the two test spots. When these test spots are aligned along a path of relative motion with the test surface, the resulting differences in height are added to form an accumulative profile of the test surface.

Optical differential profile measurement apparatus and process

An interferometer is used to locate and examine defects in a test surface of a test specimen. Defects are first located as the test surface is driven past the objective of the interferometer at a constant speed, with a darkfield interferogram being examined as it flows across a row of CCD elements. During this process, the location of each defect is stored. Next, the test specimen is sequentially moved into the locations at which static measurements are made using an area array of CCD elements. During these measurements, the phase angle relationship of the interferometer is varied so that heights of surface segments may be calculated. If some to these segments are located more than a quarter wave length of the interferometer light source from the surface at which the darkfield is established, a process is used to perform height corrections for segments within transition boundaries.

Apparatus and method for storing interferometric images of scanned

A glide height tester for inspecting a surface of a spinning magnetic disk includes a glide plate, which is mounted to pivot above the disk surface. A reflective surface fastened to the glide plate is imaged by interferometric apparatus which produces a calculated output indicating a first angle of the glide plate. The interferometric apparatus includes a Wollaston prism, which can be rotated 90-degrees to provide an output indicating a second angle of the glide plate, perpendicular to the first angle.

Apparatus for optical differential measurement of glide height above a

Inspection apparatus for determining the profile of textured spots extending in a pattern along a surface of a magnetic disk includes an interferometer which illuminates first and second, adjacently disposed test spots on the surface. The disk and the interferometer are moved, relative to one another, so that one of the test spots traverses the textured spots in the pattern while the other test spot is moved along a flat portion of the disk surface. In one embodiment, the inspection apparatus is built into the device forming the textured spots, providing feedback controlling the texturing process.

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Coconut Creek, FL, United States of America

Huizong Lu