Xyratex Technology Limited

Brown & Sharpe Surface Inspection Systems, Inc.

Display Inspection Systems, Inc.

Orbotech Limited

Gregory Toker

Andrei Brunfeld

Bryan Clark

Ilan Laver

Joseph Shamir

Ely Pekel

Liviu Singher

Zvi Yaniv

Ilia Lutsker

Brunfeld Andrei

Clark Bryan

An optical inspection system includes a polarizing isolator that reduces error in measurements by preventing ghost light reflected or scattered from element of a detection subsystem from re-entering the illumination and detection optical paths. The polarizing isolator may include a polarizing splitter that isolates light directionally according the a linear polarization state and two quarter-wave plates for transforming linearly polarized light to circularly polarized light.

Optical inspection system with polarization isolation of detection system reflections

A scatterometer-interferometer and method for detecting and distinguishing characteristics of surface artifacts provides improved artifact detection and increased scanning speed in interferometric measurement systems. A scatterometer and interferometer are combined in a single measurement head and may have overlapping, concentric or separate measurement spots. Interferometric sampling of a surface under measurement may be initiated in response to detection of a surface artifact by the scatterometer, so that continuous scanning of the surface under measurement can be performed until further information about the size and/or height of the artifact is needed.

Scatterometer-interferometer and method for detecting and distinguishing characteristics of surface artifacts

A resonant ellipsometer and method for determining ellipsometric parameters of a surface provide an efficient and low-cost mechanism for performing ellipsometric measurements. A surface of interest is included as a reflection point of a resonance optical path within a resonator. The intersection of the resonance optical path with the surface of interest is at an angle away from normal so that the complex reflectivity of the surface alters the phase of the resonance optical path. Intensity measurements of light emitted from a partially reflective surface of the resonator for orthogonal polarizations and for at least two effective cavity lengths provide complete information for computing the ellipsoidal parameters on the surface of interest. The resonator may be a Fabry-Perot resonator or a ring resonator. The wavelength of the illumination can be swept, or the cavity length mechanically or electronically altered to change the cavity length.

Resonant ellipsometer and method for determining ellipsometric parameters of a surface

A Fabry-Perot resonator apparatus and method including an in-resonator polarizing element improves detection/measurement sensitivity of an optical system, provides both fields at a single end of the resonator, and overcomes other structural and performance limitations of particular optical systems. A polarizing element, which may be a quarter-wave plate, a 45-degree Faraday rotator or other polarizing element capable of converting between linear and circular polarizations and back, is placed in the resonance path of the Fabry-Perot resonator. The polarizing element effectively doubles the cavity length and orthogonally isolates forward from reverse reflection rays within the resonator, eliminating interference between rays and providing isolated bright and dark fields at each end of the resonator. The polarizing element is introduced in a lens-incorporating Fabry-Perot resonator to eliminate cross-talk between image points and is used in a non-normal incidence Fabry-Perot resonator to emit bright and dark resonance information at either end of the resonator.

Fabry-perot resonator apparatus and method including an in-resonator polarizing element

A Fabry-Perot resonator apparatus and method for observing low reflectivity surfaces provides functional improvements for optical inspection and measurement systems, optical storage and retrieval systems as well as other optical systems when the a surface of interest in the resonator path has a lower than ideal reflectivity. The Fabry-Perot resonator is designed with an angle of incidence on the surface of interest deviating from normal incidence, effectively raising the reflectivity. Resonance is supported either by one or more reflectors oriented at angles with respect to the surface of interest, or by a focusing system that alters the directive angle of optical path(s) within the resonator such that the angle of incidence at an intersection of the optical path with the surface of interest is an angle other than normal. A normal incidence is maintained at the reflector(s), so that resonance is supported between the surface of interest and the reflector(s).

Fabry-Perot resonator apparatus and method for observing low reflectivity surfaces

Apparatus for sensing information regarding a surface including a first plurality of optical elements arranged to acquire two dimensional information about a surface, a second plurality of optical elements arranged to acquire topographical information about the surface, wherein the first plurality and the second plurality of optical elements are arranged to simultaneously provide the two dimensional information and the topographical information to at least partially non-overlapping portions of a single sensor array.

Method and apparatus for simultaneous 2-D and topographical inspection

A three-dimensional imaging resonator and method therefor provides improved surface height measurement capability in optical measuring systems. A resonator including a surface of interest in a resonant image path is coupled to an external multi-pixel detector that detects an image of intensity of light reflected from or transmitted through the resonator. An imaging system is included in the resonator to image a region of a surface of interest on another reflector forming part of the resonator. By changing an effective cavity length of the resonator, the image is 'scanned' in a direction perpendicular to the other reflector and a processing system stores information corresponding to resonance peaks to achieve a mapping of feature height above the surface of interest. The resonator effective cavity length can be changed by sweeping the illumination wavelength or by mechanically or otherwise altering the optical length of the resonator.

Three-dimensional imaging resonator and method therefor

A resonator method and system for distinguishing characteristics of surface features or contaminants provides improved inspection or surface feature detection capability in scanning optical systems. A resonator including a surface of interest in the resonant path is coupled to a detector that detects light leaving the resonator. Changes in the resonance peak positions and peak intensities are evaluated against known changes for standard scatters in order to determine the material characteristics of an artifact at the surface of interest that causes a resonance change. The lateral size of the artifact is determined by de-convolving a known illumination spot size with the changing resonance characteristics, and the standard scatterer data is selected in conformity with the determined artifact size. The differential analysis using resonance peak shifts corresponding to phase and amplitude information provides an identification algorithm that identifies at least one artifact/material type is identified from matching known behaviors of artifacts/materials.

Resonator method and system for distinguishing characteristics of surface features or contaminants

An optical inspection apparatus operates at high speed at very high resolution for detecting defects in transparent disks in a production environment. These transparent disks are of the type commonly used as disk platters in hard disk drives. This apparatus uses a laser beam directed to a polygon scanner, which provides a linear scan of the beam along a radius of the disk. The disk to be inspected is rotated such that its entire surface passes the scan path of the laser beam. The laser beam, after passing through the unit to be inspected, is directed to a parallel detector array, which detects changes in the nominal Gaussian distribution of the laser beam that correspond to defects in the surface of the transparent disk above a programmable threshold level. This parallel detection method allows the inspection apparatus to identify defects much smaller than the diffraction limits of the optics used, and will accurately identify changes of the laser beam caused by defects in the disk. An automatic disk handler loads untested disks into the apparatus and unloads and sorts tested disks according to the results of the inspection.

High speed optical inspection apparatus for a transparent disk using gaussian distribution analysis and method therefor

An optical inspection apparatus operates at high speed at very high resolution for detecting defects in reflective disks in a production environment. These reflective disks are of the type commonly used as disk platters in hard disk drives. This apparatus uses a laser which provides a light beam directed to a polygon scanner, which provides a linear scan of the beam along a radius on both sides of the disk by using two mirrors to direct the light beam. The disk to be inspected is rotated such that its entire surface passes the scan path of the light beam. The light beam is reflected off the reflective disk, and returns to the scanning optics and the polygon scanner in a path coincident with the transmitted light beam. The reflected light beam is distinguished from the transmitted light beam by using a beam splitter to direct the reflected light beam to a parallel detector array, which detects changes in the nominal Gaussian distribution of the light beam that correspond to defects in the surface of the reflective disk above a programmable threshold level. This parallel detection method allows the inspection apparatus to identify defects much smaller than the diffraction limits of the optics used, and will accurately identify changes in the light beam caused by defects in the disk. An automatic disk handler loads untested disks into the apparatus and unloads and sorts tested disks according to the results of the inspection.

High speed surface inspection optical apparatus for a reflective disk using gaussian distribution analysis and method therefor

An optical inspection apparatus operates at high speed at very high resolution for detecting defects in transparent flat panels in a production environment. This apparatus uses a laser which provides a light beam directed to a polygon scanner, which provides a linear scan of the beam along the width of the flat panel. The flat panel to be inspected is moved such that its entire surface passes the scan path of the light beam. The light beam passes through the transparent flat panel, and is reflected off a spherical mirror, back through the transparent flat panel, and returns to the scanning optics and the polygon scanner in a path coincident with the transmitted light beam. The reflected light beam is distinguished from the transmitted light beam by using a beam splitter to direct the reflected light beam to a parallel detector array, which detects changes in the nominal Gaussian distribution of the light beam that correspond to defects in the surface of the transparent flat panel above a programmable threshold level. This parallel detection method allows the inspection apparatus to identify defects much smaller than the diffraction limits of the optics used, and will accurately identify changes in the light beam caused by defects in the flat panel. An automatic flat panel handler loads untested flat panels into the apparatus and unloads and sorts tested flat panels according to the results of the inspection.

High speed optical inspection apparatus for a large transparent flat panel using gaussian distribution analysis and method therefor

An optical inspection apparatus operates at high speed at very high resolution for detecting defects in flat, polished media in a production environment. The configuration of the first embodiment is used to inspect transparent disks such as those used as disk platters in hard disk drives. The configuration of the second embodiment is used to inspect reflective disks. The configuration of the third embodiment is used to inspect transparent flat panels such as those commonly used in Liquid Crystal Display (LCD) panels. All embodiments use a laser providing a light beam directed to a polygon scanner, which provides a linear scan of the beam. The unit to be inspected is moved such that its entire surface passes the scan path of the light beam. The light beam, after contacting the unit to be inspected, is directed to a parallel detector array, which detects changes in the nominal Gaussian distribution of the light beam that correspond to defects above a programmable threshold level. This parallel detection method allows the inspection apparatus to identify defects much smaller than the diffraction limits of the optics used, and will accurately identify changes in the light beam caused by defects in the media. An automatic media handler loads untested units into the apparatus and unloads and sorts tested units according to the results of the inspection.

High speed optical inspection apparatus using Gaussian distribution analysis and method therefore

A high speed, high sensitivity inspection system (10) is provided, which is substantially impervious to external factors such as vibration. The inspection system is an optical system which employs phase contrast interferometry to achieve the desired results. The systems makes use of a 'black beam' at the optical axis of the system, and uses at least two detectors to determine the intensity of the light beam after passing through a work piece.

Differential phase contrast inspection system with multiple detectors

A high speed, high sensitivity inspection system (10) is provided, which is substantially impervious to external factors such as vibration. The inspection system is an optical system which employs phase contrast interferometry to achieve the desired results.

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Jerusalem, Israel

Gregory Toker