Abstract: A sensor and method for determining the optical properties of a sample material is disclosed. The sensor comprises a light source that generates a linearly polarized light beam having a predetermined polarization orientation with respect to the plane of incidence. The linearly polarized light beam is reflected off the sample and is split into second and third light beams where the second and third light beam consist of the combined projections of mutually orthogonal components of the first light beam. A signal processor measures the intensity difference between the second and third light beams to calculate the phase difference induced by the sample material.

Abstract: The invention concerns an ellipsometer comprising: a source (2) capable of emitting a broadband ray (4), a polarizer (10) for producing a polarised incident beam (12) adapted to illuminate a sample (16) according to at least a selected angle; an analyzer (24) providing an output beam (28) in response to said reflected beam (20) and at least a reflecting optical element (14) arranged between the source (2) and the sample (16) and/or between the sample (16) and the sensor, and capable of focusing the incident beam (12) and/or the reflected beam (20) according to a selected spot The ellipsometer further comprises at least a first refracting optical element (22) arranged between the sample (16) and the sensor and/or between the source (2) and the sample (16) to collect and focus said reflected beam and/or said incident beam, thereby enabling to provide at least a refracting element (22) and a reflecting element (14) on either side of the sample (16) and hence to place the source and the sensor on the same side re

Abstract: A surface inspection apparatus (100) comprises a light (10) source for emitting a light beam L0, an optical illumination system (30) for projecting the light beam on an inspected surface (220) formed by a film 210, an optical detection system (50) having lenses to spatially split reflection lights and an aperture stop (60) having apertures disposed with polarization elements (61–64) for transilluminating mutually different polarized light components, a light intensity detection device (41–44) for individually detecting the light intensities of the respective reflection lights passed through the respective polarization elements, a scanning device (20), and an arithmetic processing device (70) for detecting the polarization conditions of the respective reflection lights and obtaining a film thickness of the film and at least one of the physical properties of the film.

Abstract: A plurality of captured images of a still subject are obtained by changing at least one of a position and a direction of illumination of a light source to illuminate the still subject. Sequenced frame images are formed based on the captured images. The sequenced frame images are sequentially switched so that the selected ones can be displayed.

Abstract: Quasi-achromatic multi-element lens(es) which are precisely mounted with respect to one another in a tubular mounting fixture, and the application thereof in focusing, (and optionally re-colliminating), a spectroscopic electromagnetic beam into a very small, chromatically relatively undispersed, area spot on a material system.

Abstract: System and methodology for controlling a beam spot size where it impinges onto a sample, and/or discriminant selection and analysis of data from detector elements in a two dimensional detector array which correspond to identified regions on a sample.

Abstract: The present invention relates to a method for inspecting a crack in a metal surface or the like, and, particularly, to an inspection method and apparatus for nondestructive inspection such as liquid penetrant inspection and magnetic particle testing. The present invention provides a flaw inspection method that essentially comprises the steps of illuminating a surface of a sample to be inspected, obtaining an image of the surface, characterizing a potential flaw on the inspected surface by processing the obtained image, displaying an image of the potential flaw, verifying that the potential flaw is a true flaw, and storing an image of the verified flaw in memory.

Abstract: A high-sensitivity reflection measurement apparatus disposed in an optical path between a light emitter and a detector of an analysis apparatus comprises an incident-side optical element, which bends the optical path of measurement light emitted from the light emitter such that the angle of incidence of the measurement light so emitted with respect to a sample surface under measurement ranges from 70° inclusive to 90° exclusive with respect to the direction perpendicular to the sample surface under measurement. The measurement light is transmitted as linearly polarized light having a desired oscillation direction, and is incident on the sample surface under measurement. Information related to the measured sample surface is obtained from light reflected from the measured sample surface when the linearly polarized light from the incident-side optical element is incident on the sample surface.

Abstract: A combined ellipsometer and oscillator system applied to a chamber for containing fluid, and method of decorrelated determination of thickness and optical constants of depostable materials present in a fluid. In use the ellipsometer determines the product of thickness and optical constant, and the oscillator system changes frequency of oscillation proportional to the thickness of material deposited upon a surface of an element therein.

Abstract: A device for ellipsometric two-dimensional display of a sample placed in an incident medium, observed between an analyser and a polarizer intersected by convergent light reflection, wherein the ellipsometric parameters of the assembly formed by the sample and a substrate whereon it is placed, are used. The substrate comprises a support and a stack of base layers and its ellipsometric properties are known. The ellipsometric properties of the substrate are such that variations of the sample ellipsometric parameters are displayed with contrast higher that the contrast produced in the absence of the substrate. The invention also concerns a display method and an ellipsometric measurement method with spatial resolution.

Abstract: There is described an improved Surface Reflectance Instrument which achieves more complete detection of surface defects in the nature of small particles. One of the improvements is the use of an elliptical integrated cavity with internal surface mirrors, and another the use of a position sensing diode as the detector for the scattered light. Other improvements and the use of a stable laser at a particular wavelength resulting in greater detection are also described.

Abstract: An apparatus is disclosed for obtaining ellipsometric measurements from a sample. A probe beam is focused onto the sample to create a spread of angles of incidence. The beam is passed through a quarter waveplate retarder and a polarizer. The reflected beam is measured by a detector. In one preferred embodiment, the detector includes eight radially arranged segments, each segment generating an output which represents an integration of multiple angle of incidence. A processor manipulates the output from the various segments to derive ellipsometric information.

Abstract: An optical inspection device includes a light source for generating a probe beam. The probe beam is focused onto a sample to create a spread of angles of incidence. After reflecting from the sample, the light is imaged onto a two dimensional array of photodetectors. Prior to reaching the detector array, the beam is passed through a rotating compensator. A processor functions to evaluate the sample by analyzing the output of the photodetectors lying along one or more azimuthal angles and at different compensator positions.

Abstract: A system for analyzing a thin film uses an energy beam, such as a laser beam, to remove a portion of a contaminant layer formed on the thin film surface. This cleaning operation removes only enough of the contaminant layer to allow analysis of the underlying thin film, thereby enhancing analysis throughput while minimizing the chances of recontamination and/or damage to the thin film. An energy beam source can be readily incorporated into a conventional thin film analysis tool, thereby minimizing total analysis system footprint. Throughput can be maximized by focusing the probe beam (or probe structure) for the analysis operation at the same location as the energy beam so that repositioning is not required after the cleaning operation. Alternatively, the probe beam (structure) and the energy beam can be directed at different locations to reduce the chances of contamination of the analysis optics.

Abstract: A liquid crystal based polarimetric system, a process for the calibration of this polarimetric system, and a polarimetric measurement process intended for measuring the representative parameters of a sample in which the polarimetric system contains an excitation section emitting a light beam that passes through a polarization state generator (PSG) and onto a sample. After reflection or transmission by the sample, the beam goes through an analysis section with a polarization state detector (PSD). The PSG and PSD each have a first and a second liquid crystal elements LCj (j=1,2) having, for each LCj element of the PSG (respectively for each LCj element of the PSD), an extraordinary axis making an angle ?j (resp. ??j) with respect to the polarization direction (i), and a retardation ?j (resp (??j) between its ordinary and extraordinary axes, the liquid crystals LCj elements being positioned in reverse order in the PSD with respect to the LCj elements of the PSG.

Abstract: A device and method for testing a slider of a head-gimbal assembly during disc drive manufacturing. The device includes a test disc, an actuator arm and a control module. The test disc has a first circumferential area for detecting contact between the slider and the test disc and a second circumferential area for burnishing sliders that contact the first circumferential area as the test disc rotates at or above the predetermined velocity. The head-gimbal assembly is affixed to a support, or flexure, on the actuator arm such that the slider is operable to move between an inner diameter and an outer diameter of the test disc. The control module controls rotation of the test disc and movement of the actuator arm, and thus the slider, relative to the test disc. The control module monitors the slider-disc interface for contact therebetween. If contact is detected, the slider is either burnished or the head-gimbal assembly is discarded altogether.

Abstract: With extremely-thin-film and thin-film measurement, models are formed based upon a combination of film thickness, optical constants obtained using the dispersion formula, incident angle, etc., and the model and measured spectrums are fit by BLMC for a single layer of a structure with a certain number of iterations, obtaining information regarding the single layer. With thin-film multi-layer-structure measurement, models are formed for multiple layers of a thin-film multi-layer structure likewise, and fit by BLMC or EBLMC, obtaining information regarding the thin-film multi-layer structure. In either measurement, light is cast onto a thin film on a substrate to be measured while changing the wavelength as a parameter in order to obtain the spectrums ?E(?i) and ?E(?i) for each wavelength ?i, representing the change in polarization between the incident and reflected light. The measured spectrums are fit, obtaining the best model. The results are confirmed and stored, as necessary.

Abstract: Methods and apparatus for measuring an electromagnetic radiation response property associated with a substrate are disclosed. The methods and apparatus generate electromagnetic waves and capture a portion of the generated waves after the waves pass through a first polarized filter, reflect from a substrate, and pass through a second polarized filter arranged in a cross polar arrangement with respect to the first polarized filter. Digital data is determined from the captured electromagnetic waves. Based on the digital data, the customer is given certain choices and/or informed of certain personal care product recommendations.

Abstract: Disclosed are spectroscopic ellipsometer systems which include polarizer and analyzer elements which remain fixed in position during data acquisition, and at least one continuously rotating or step-wise rotatable compensator which transmits an electromagnetic beam therethrough and imposes a continuously variable or plurality of sequentially discrete polarization states on a beam of electromagnetic radiation; and at least one multiple element lens which also transmits the electromagnetic beam therethrough.

Abstract: An imaging method and apparatus are provided, including a light source emitting a polarized light beam, and an optical assembly including a control layer and/or a light reflection surface. The control layer advantageously allows for control over the properties of a generated evanescent wave to optimize an image of a specimen array within the evanescent wave. The light reflection surface includes coupling means used to couple a receptor/capture agent advantageously allowing for flexible control over receptor specific regions.

Abstract: Time efficient methodology for investigating a sample system using electromagnetic wavelengths which are not absorbed by oxygen and/or water vapor during evacuation or purging of a substantially enclosed space in which is present the sample system, followed by using wavelengths which are absorbed by oxygen and/or water vapor after the evacuation or purging is sufficiently completed.

Abstract: Use of differences in spectroscopic spectra resulting from multiple sample investigation, or sequential investigation of the same sample in evaluation of sample characterizing parameters such as ultra-thin film thickness.

Abstract: A method of determining the actual properties of a film stack. An incident beam of light is directed towards the film stack, such that the incident beam of light is reflected from the film stack as a reflected beam of light. The actual properties of the reflected beam of light are measured, and properties of the film stack are estimated. A mathematical model of the film stack is solved with the estimated properties of the film stack to yield theoretical properties of the reflected beam of light. The theoretical properties of the reflected beam of light are compared to the actual properties of the reflected beam of light to yield a cost function. The estimated properties of the film stack are iteratively adjusted and the mathematical model is iteratively solved until the cost function is within a desired tolerance. The estimated properties of the film stack are reported as the actual properties of the film stack.

Abstract: Disclosed is a method for determination of bulk refractive indicies of flowable liquids utilizing thin films thereof on a roughened surface of a rigid or semi-rigid object.

Abstract: Disclosed is an achromatic spectroscopic ellispometer for analyzing small regions of a sample over a wide range of wavelengths from ultraviolet (UV) to infrared (IR). The spectroscopic ellipsometer contains a light source emitting a light beam which passes through a polarisation state generator section before being focused at an incidence angle q by a first parabolic mirror to a small spot on a sample. A second parabolic mirror collects the reflected beam and connects said beam to an analyzing section. The reflected beam emerges from the analyzing section and is spectroscopically detected and analyzed. The light beam through the polarisation state generator section up to the first parabolic mirror and the light beam from the second mirror through the analyzing section are parallel enabling achromatism. The incidence angle q is largely varied without shifting of the location of the small spot on the sample surface.

Abstract: Generally, and in one form of the present invention, is a polarization-maintaining fiber-based polarization sensitive optical low coherence reflectometer for depth resolved birefringence measurement. With the present invention, linear birefringence of a sample may be measured from data recorded in a single A-Scan. In addition, the present invention provides for the simultaneous measurement of retardation and orientation of birefringent axes, wherein measured retardation is insensitive to sample rotation in the plane perpendicular to ranging.

Abstract: A normal incidence rotating compensator ellipsometer includes an illumination source that produces a broadband probe beam. The probe beam is redirected by a beam splitter to be normally incident on a sample under test. Before reaching the sample, the probe beam is passed through a rotating compensator. The probe beam is reflected by the sample and passes through the rotating compensator a second time before reaching a detector. The detector converts the reflected probe beam into equivalent signals for analysis.

Abstract: Before the diffraction from a diffracting structure on a semiconductor wafer is measured, where necessary, the film thickness and index of refraction of the films underneath the structure are first measured using spectroscopic reflectometry or spectroscopic ellipsometry. A rigorous model is then used to calculate intensity or ellipsometric signatures of the diffracting structure. The diffracting structure is then measured using a spectroscopic scatterometer using polarized and broadband radiation to obtain an intensity or ellipsometric signature of the diffracting structure. Such signature is then matched with the signatures in the database to determine the grating shape parameters of the structure.

Abstract: A sample, in which a dielectric film having a dielectric constant equal to or larger than 50 (based on electrical measurement) is formed on a substrate, is measured by an ellipsometer while a model corresponding to the sample is formed based on effective medium approximation (EMA). A film corresponding to the dielectric film of the model includes void volume fraction between 60% and 90%. A calculated value based on the model is compared with a value measured by the ellipsometer and fitting is applied to decrease a difference between the compared values in order to specify the thickness and the optical constant of the sample.

Abstract: Determination of thin metal film dielectric function and layer thicknesses using simultaneous transmission spectroscopic ellipsometric (SE) and transmission intensity (T) measurements obtained in-situ to break correlation between thickness and optical constants of very thin absorbing films, preferably using only A.C. Components of ellipsometric and intensity characterizing electromagnetic radiation which transmits through said substrate and enters a detector.

Abstract: The present invention provides a hand held dermoscopy epiluminescense device having a generally circular optical magnification lens incorporated into the housing of the device. A lighting array provides the light necessary for medical examination of the skin. The lighting array comprises a ring of LEDs comprising four different colored sets of LEDs each on a different lighting circuit. The four colors comprise White, UV/Blue (405 nm), green/yellow (565 nm) and orange/red (630 nm). A second embodiment provides a hand held dermoscopy epiluminescense device with a magnification lens and an associated ring of luminous diodes powered by an on board battery. Every other diode in the ring operates as first and second light sources. The even diodes are filtered by a first polarization ring and the odd diodes are filtered by a second polarization ring. Each polarization ring has an open center for the lens and openings sized and positioned to correspond to the even or odd diodes to only filter one set.

Abstract: The present invention is a hand held dermoscopy epiluminescense device with a magnification lens and an associated ring of luminous diodes powered by an on board battery. Every other diode in the ring operates as first and second light sources. The even diodes are filtered by a first polarization ring and the odd diodes are filtered by a second polarization ring. Each polarization ring has an open center for the lens and openings sized and positioned to correspond to the even or odd diodes to only filter one set. A viewing polarizer is provided and is cross-polarized relative to the first polarization ring and is parallel-polarized with the second polarization ring. A three way switch which provides on demand cross-polarized, parallel-polarized and a combination thereof for epiluminescence. A second embodiment provides even diodes of a first color and odd diodes of a second color.

Abstract: A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system being present in an environmental control chamber.

Abstract: The testing method for a polarizing plate includes the following two types of testing: a selected light beam passing through a filter, a polarizer, a concave lens and a filter, a mirror, a concave lens and finally to a sample of a polarizing plate; the sample is rotated along z-axis to ascertain that if there is any variation of shade in an optical domain, in order to differentiate defective samples from qualified ones. By applying the method, gooseflesh in the sample is ascertained by naked eyes easily while feeding; the checking result can be reflected to a factory owner. The test cost is low and requires only inexpensive instruments. Moreover, an additional processing of polarizing plate is needless.

Abstract: Disclosed is methodology for obtaining data of improved precision, including detection and replacement of data determined to be suspect to provide good data over a spectroscopic range of wavelengths.

Abstract: Methods and instruments are provided for measuring differences in fractional reflectivity changes between transverse electric (TE or s-polarized) and transverse magnetic (TM or p-polarized components of an obliquely incident light with high sensitivity and low noise. Also provided are high sensitivity, low noise methods and instruments for measuring differences in fractional reflectivity changes between R-polarized (right-circularly polarized) and L-polarized (left-circularly polarized) components of a near-normal incident light. The methods take advantage of a nulling step to minimize harmonics of the optical signal derived from a first sample. Determination of odd and even harmonics of the optical signal derived from a second sample allows determination of refractive index and optical absorption coefficient differences between two samples to be determined with high sensitivity and low noise.

Abstract: The measurement spot size of small-spot reflectometers, ellipsometers, and similar instruments can be reduced by placing an optical fiber along the optical path of the instrument, such as between an illumination source and a sample or the sample and a detector. The angular range of the probe beam can be adjusted to be less than a natural numerical aperture of the optical fiber. A multimode fiber can be used, which can have a controllable amount of bend or coil, such that rays entering the fiber at larger angles of incidence are attenuated more than rays entering at shallow angles of incidence. Light passing through the fiber can be selectively attenuated and partially mixed to reduce the presence of secondary maxima falling outside the measurement spot. Minimizing these secondary maxima can improve the amount of light measured by the detector that is reflected from inside the measurement spot.

Abstract: A method and apparatus for enhancing image contrast between resist-covered and bare silicon regions of a wafer, applicable to Edge Bead Removal inspection. The wafer is illuminated separately by s-polarized light and p-polarized light impinging at near the Brewster angle of silicon or resist, and an image difference between the reflected s-polarized light and the reflected p-polarized light is derived.

Abstract: A machine-vision system that provides quick changing and/or automatic adjustment of illumination angle, dispersion, intensity, and/or color of illumination. One such system includes a light source emitting polarized light, a machine-vision imager, an image processor operative to generate a quality parameter based on an image, and one or more of the means described above for selectively directing the light in a predetermined pattern based on its polarization and based on the quality parameter of the image. Some embodiments include an imager, a controllable light source, first and second optical elements that selectively direct light in first and second patterns, and a controller controlling the light characteristics using the first and/or second light patterns.

Abstract: Disclosed is a system and method of aligning, preferably by an automated procedure, a beam of electromagnetic radiation provided by a source thereof so that it approaches a sample at a specific location upon its surface, at a known angle, then reflects therefrom and enters a data detector.

Abstract: An ellipsometric apparatus provides two impinging focused probe beams directed to reflect off the sample along two mutually distinct and preferably substantially perpendicular directions. A rotating stage rotates sections of the wafer into the travel area defined by two linear axes of two perpendicularly oriented linear stages. As a result, an entire wafer is accessed for measurement with the linear stages having a travel range of only half the wafer diameter. The reduced linear travel results in a small travel envelope occupied by the wafer and, consequently, a small footprint of the apparatus. The use of two perpendicularly directed probe beams permits measurement of periodic structures along a preferred direction while permitting the use of a reduced motion stage.

Abstract: A semiconductor wafer having two regions of different dopant concentration profiles is evaluated by performing two (or more) measurements in the two regions, and comparing measurements from the two regions to obtain a reflectivity change measure indicative of a difference in reflectivity between the two regions. Analyzing the reflectivity change measure yields one or more properties of one of the regions if corresponding properties of the other region are known. For example, if one of the two regions is doped and the other region is undoped (e.g. source/drain and channel regions of a transistor), then a change in reflectivity between the two regions can yield one or more of the following properties in the doped region: (1) doping concentration, (2) junction or profile depth, and (3) abruptness (i.e. slope) of a profile of dopant concentration at the junction. In some embodiments, the just-described measurements in the two regions are performed by use of only one beam of electromagnetic radiation.

Abstract: In an apparatus which determines characteristics of a thin film according to the present invention, a temporal change in a refractive index n and an extinction coefficient k of a thin film in a period from start of a change in the thin film as a processing target (e.g., melting) to end of the change (e.g., solidification) can be obtained with a high time resolution of pico-seconds. Based on this, it is possible to know a progress of a change in state of the thin film (e.g., crystallization) or a transition of growth of crystal grains in units of pico-seconds.

Abstract: Methods and apparatus for scanning of a microarray to provide an image of the microarray are disclosed. Data related to change in polarization state of a scanning light beam for individual points or lines or other portion of the microarray are collected and processed to image the microarray at high resolution and speed.

Abstract: The present invention discloses simple and yet highly efficient configurations of optical coherence domain reflectometry systems. The combined use of a polarizing beam splitter with one or two polarization manipulator(s) that rotate the returned light wave polarization to an orthogonal direction, enables one to achieve high optical power delivery efficiency as well as fixed or predetermined output polarization state of the interfering light waves reaching a detector or detector array, which is especially beneficial for spectral domain optical coherence tomography. In addition, the system can be made insensitive to polarization fading resulting from the birefringence change in the sample and reference arms. Dispersion matching can also be easily achieved between the sample and the reference arm for high resolution longitudinal scanning.

Abstract: An apparatus designed to examine a surface includes a polarization analyser element, or analyser, placed in the path of a light beam reflected by the surface, a device configured to take digital images and placed in the path of the beam reflected by the surface downstream of the analyser, and a processing unit capable of calculating the color and the intensity of a plurality of pixels of at least one image.

Abstract: A method for producing a library includes the steps of calculating a plurality of conditions for a reflection light from a periodic pattern by changing the sectional shape of the periodic pattern, a condition of an incident light which is emitted to the periodic pattern, an optical constant of a material which forms the periodic pattern, relating a plurality of the libraries to the plurality of the reflection light's conditions, and the optical constant corresponding to the plurality of the reflection light's conditions respectively.

Abstract: A normal incidence reflectometer includes a rotatable analyzer/polarizer, which permits measurement of a diffracting structure. Relative rotation of the analyzer/polarizer with respect to the diffracting structure permits analysis of the diffracted radiation at multiple polarity orientations. A spectograph detects the intensity of the spectral components at different polarity orientations. Because the normal incidence reflectometer uses normally incident radiation and an analyzer/polarizer that rotates relative to the diffracting structure, or vice-versa, the orientation of the diffracting structure does not affect the accuracy of the measurement. Thus, the sample holding stage may use X, Y, and Z, as well as r-? type movement and there is no requirement that the polarization orientation of the incident light be aligned with the grating of the diffraction structure.

Abstract: A flow cytometer includes an optical flow cell through which particles to be characterized on the basis of at least their respective side-scatter characteristics are caused to flow seriatim. A plane-polarized laser beam produced by a laser diode is used to irradiate the particles as they pass through a focused elliptical spot having its minor axis oriented parallel to the particle flow path. Initially, the plane of polarization of the laser beam extends perpendicular to the path of particles through the flow cell. A half-wave plate or the like is positioned in the laser beam path to rotate the plane of polarization of the laser beam so that it is aligned with the path of particles before it irradiated particles moving along such path.

Abstract: A confocal scanning microscope system (10) using cross polarization effects and an enhancement agent (acetic acid) to enhance confocal microscope reflectance images of the nuclei of BCCs (basal cell carcinomas) and SCCs (squamous call carcinomas) in the confocal reflectance images of excised tumor slices. The confocal scanning microscope system having a laser (11) for generating an illumination beam (12), a polygon mirror (18) for scanning the beam to a tissue sample (22) and for receiving a return beam from the tissue sample and detector (28) for detecting the returned beam to form an image. The system further includes a half-waveplate (13) having a rotatable stage (14) and a quarter-wave plate (21) having a rotatable stage (20) disposed in the optical path of the illumination beam and at least a linear polarizer (24) having a rotatable stage (25) disposed in the optical pat of the returned beam from the tissue sample.