Kla Tencor Corporation

Phase Metrics, Inc.

Carlos A Duran

Kenneth H Womack

Christopher A Lacey

Harald F Hess

Rui-Fang Shi

David Reese Peale

Semyon Nodelman

Ed Ross

The present invention is a method for providing a disk of an optical tester. The disk comprises a transparent substrate that has a first surface and an opposite second surface. The disk also includes a coating on the first surface of the transparent substrate. An identical coating can be applied to the second surface of the transparent substrate. The coating can have multiple layers of thin films. The present invention provides a method to determine the required thickness of the coating to enhance the sensitivity of zero flying height measurement.

Coatings for sensitivity enhancement of signal from glass disks

An interferometer that contains a tri-coupler to mix light from three different waveguides. The light is emitted from a light source and may be reflected from a test surface. The output of the tri-coupler may be three different light beams that have intensities 120 degrees out of phase from each other. The out-of-phase light beams may be detected by a plurality of photodetectors. The detected out-of-phase light beams may be used to determine a height of the test surface. The waveguides and tri-coupler provide a compact and relatively inexpensive interferometer.

Waveguide based parallel multi-phaseshift interferometry for high speed metrology, optical inspection, and non-contact sensing

A calibration medium that is used to calibrate a flying height tester which measures the gap of an air bearing formed between a magnetic recording head and a substrate. The medium contains a first ridge and a second ridge that extend from an underlying substrate. The ridges may be coated with a reflective material. A flying height tester can be calibrated by measuring light reflected from each ridge. The ridges have varying thicknesses so that the calibration medium will produce multiple data points.

Thin film flying height calibration disk for calibrating flying height

An apparatus and method for measuring the space between a transparent member such as a substrate, and reflective member such as a slider. The apparatus includes a first optical system which detects a first light beam that is reflected from the substrate and the slider. The reflected light is separated into four separate beams. The intensities of the beams are detected and utilized to determine a first stokes parameter, a second stokes parameter, a third stokes parameter and a fourth stokes parameter of the reflected light. The stokes parameters are used to compute the real index of refraction n, extinction coefficient k and the thickness of the space. The four stokes parameters account for any depolarized light that is reflected from the slider. The first optical system may have a photodetector which detects an image of the slider. The image provides multiple data points that can be used to calculate n, k and the thickness of the air gap without a retract routine. The apparatus may also have a second optical system which detects a second light beam reflected from the substrate and the slider. The second optical system can be used to dynamically measure a thickness of the space. In the combined system the first optical system may accurately measure the n and k of a slider area while the second optical system dynamically measures the thickness of the air gap.

Growing community of inventors

San Diego, CA, United States of America

Carlos A Duran