Abstract: Test equipment determines the contents of medical fluids to be delivered to a patient by a medication delivery system by measuring optical properties of the fluids. One system provides a non-invasive test that uses optical rotation caused by optically active pharmaceutical substances to determine the presence or absence of the pharmaceutical substances within a medical fluid. Another system provides a non-invasive test that uses refractive index properties to determine the concentration of a pharmaceutical substance within the fluid. A method for use is also disclosed.

Abstract: The present invention aims to provide a polarization modulation imaging ellipsometer capable of measuring ellipsometric parameters of the surface of a sample for each of the measured points with high precision and at high speed.

Abstract: A polarization stabilizing device and method based on controlling the phase retardation of a pair of variable phase retarders with a controller such that the first of the variable retarders has its phase retardation switched between first and second values whenever the phase retardation of the second of the variable retarders reaches an upper or a lower limit. The upper and lower limits of the second retarder and the first and second values of the first retarder are chosen so that discontinuities in the power of the output optical signal are avoided when the first variable retarder is switched, thereby providing endless polarization stabilization using phase retarders that themselves have only limited retardation ranges.

Abstract: Preferred embodiments of the present invention are directed at limiting power and controlling an output intensity of an optical system using photo-induced anisotropic materials. In a preferred embodiment, an azobenzene polymer film is used. The embodiments in accordance with the present invention include a cross-polarization system to provide clamping of the output intensity.

Abstract: In a process of manufacturing a semiconductor device, after a gate oxide film is formed, the thickness of the gate oxide film is measured by measuring an exposure period defined from a time at which the oxide film is formed to a time at which the thickness of the oxide film is measured. In addition, if necessary, the measurement of the oxide film is corrected to determine the real thickness based on the exposure period. Accordingly, the thickness of the gate oxide film can be measured accurately.

Abstract: A method is disclosed for measuring the dose and energy level of ion implants forming a shallow junction in a semiconductor sample. In the method, two independent measurements of the sample are made. The first measurement monitors the response of the sample to periodic excitation. In the illustrated embodiment, the modulated optical reflectivity of a reflected probe beam is monitored to provide information related to the generation of thermal and/or plasma waves in the sample. A second spectroscopic measurement is also performed. This measurement could be either a spectroscopic reflectometry measurement or a spectroscopic ellipsometry measurement. The data from the two measurements are combined in a manner to yield information about both the dose (concentration) of the dopants as well as the energy used to inject the dopants in the semiconductor lattice. The method will useful in controlling the formation of shallow junctions.

Abstract: A fiber polarimeter has one or more oblique fiber Bragg gratings disposed one behind the other in a fiber. The fiber Bragg gratings couple out portions of a light wave input to the fiber depending on its polarization. For more than one fiber Bragg grating a wave plate is disposed in the fiber between consecutive fiber Bragg gratings. The portions of the light wave from the fiber Bragg grating(s) are detected to produce measurement data that is used to calculate four Stokes parameters for determining polarization, degree of polarization and/or power of the light wave.

Abstract: A method is disclosed for measuring the dose and energy level of ion implants forming a shallow junction in a semiconductor sample. In the method, two independent measurements of the sample are made. The first measurement monitors the response of the sample to periodic excitation. In the illustrated embodiment, the modulated optical reflectivity of a reflected probe beam is monitored to provide information related to the generation of thermal and/or plasma waves in the sample. A second spectroscopic measurement is also performed. This measurement could be either a spectroscopic reflectometry measurement or a spectroscopic ellipsometry measurement. The data from the two measurements are combined in a manner to yield information about both the dose (concentration) of the dopants as well as the energy used to inject the dopants in the semiconductor lattice. The method will useful in controlling the formation of shallow junctions.

Abstract: A semiconductor impurity concentration testing apparatus includes a terahertz pulse light source that irradiates terahertz pulse light on a semiconductor material, a light detector that detects transmitted pulse light having been transmitted through the semiconductor material, a measurement device that ascertains a spectral transmittance based upon a time-series waveform of the electric field intensity of the transmitted pulse light and an arithmetic operation unit that calculates an impurity concentration in the semiconductor material based upon the spectral transmittance. By adopting such a structure, it becomes possible to measure and test the impurity concentration over the entire semiconductor material in a simple manner and to reproduce an image of the impurity distribution.

Abstract: A method is disclosed for measuring the dose and energy level of ion implants forming a shallow junction in a semiconductor sample. In the method, two independent measurements of the sample are made. The first measurement monitors the response of the sample to periodic excitation. In the illustrated embodiment, the modulated optical reflectivity of a reflected probe beam is monitored to provide information related to the generation of thermal and/or plasma waves in the sample. A second spectroscopic measurement is also performed. This measurement could be either a spectroscopic reflectometry measurement or a spectroscopic ellipsometry measurement. The data from the two measurements are combined in a manner to yield information about both the dose (concentration) of the dopants as well as the energy used to inject the dopants in the semiconductor lattice. The method will useful in controlling the formation of shallow junctions.

Abstract: An apparatus (10) for analyzing lubricant oils and functional fluids includes an optical emission spectrometer (OES) (26) having a substantially continuously valued wavelength versus intensity output (140). The OES (26) analyzes light captured from a spark emission stand (58) through which the fluid sample is flowed. An expert system (160-172) operates according to a set of Rules, and generates diagnostic text (174) for an operator based on the information about the fluid sample provided by the OES (26) and other measurement devices. The apparatus (10) includes an airflow passage (154) in the OES (26) spark enclosure that is characterized by airflow substantially parallel to the spark electrodes (128, 130) promoting even-wear of the electrodes.

Abstract: A cloud condensation nucleus spectrometer having a streamwise segmented condensation nucleus growth column. The condensation nucleus growth column includes alternating hot and cold temperature-maintaining segments arranged next to one another. The temperature difference between adjacent hot and cold temperature-maintaining segments increases from the input opening to an output opening of the condensation nucleus growth column to produce a supersaturation distribution that increases from the input opening to the output opening.

Abstract: Method for detecting an analyte of interest, comprising the steps of providing a detection device comprising a light reflective or transmissive substrate supporting one or more layers comprising an adhering attachment layer to which is affixed a receptive material which specifically interacts with the analyte of interest; reacting the device with a sample potentially comprising the analyte under conditions in which the analyte binds to the receptive material; and reacting bound analyte with a reagent which creates a mass change on the surface of the device.

Abstract: System and method for inspecting a container for defects. A first polarizer positioned between a light source and the container polarizes light provided by the light source for illuminating the container. A second polarizer positioned between the container and a camera polarizes the light transmitted through the container to the camera. As positioned, the axes of transmission of the first and second polarizers are non-parallel relative to each other. An image processor processes an image generated by the camera as a function of an optical characteristic of the image to detect defects in the container.

Abstract: A scribe mark reader (10) uses a source of circularly polarized light and a holographic beam-shaping optical element (40) to uniformly illuminate an area of a substrate (20) that includes a scribe mark (18). Light incident on the substrate at a scribe mark is predominantly scattered, whereas light incident on the substrate at a processed area (30) of the wafer surface between the pits (28) of the scribe mark is predominantly specularly reflected. The phase-reversed, specularly reflected light from the processed area is blocked by a circular analyzer that passes light scattered from the scribe mark. Light passing the polarizer can then be used to form an image of the scribe mark. The intensity of the images formed are sufficiently consistent that the automatic gain control of the CCD camera can be used and the images formed can be readily interpreted by optical character recognition software.

Abstract: A particle monitor includes a light source for transmitting a light into a space over a wafer in wafer processing equipment to irradiate particles floating above the wafer for causing a scattered light; a photo-detector for detecting the scattered light to generate output signals corresponding to the intensity of the scattered light; a signal intensity judgment device for receiving the output signals from the photo-detector and comparing the output signals with a predetermined reference value already set in the signal intensity judgment device so as to judge whether the intensity of the scattered light is higher or lower than the predetermined reference value; and a display for displaying the intensity of the scattered light and luminance and distribution in intensity thereof or displaying distributions in size and the number of particles.

Abstract: A silicon wafer measuring method includes: (a) a first step of measuring a light transmission characteristic (I.sub.OBS) of the pulled silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the pulled silicon wafer, (b) a second step of measuring a light transmission characteristic (I.sub.O) of a floating zone silicon wafer functioning as a reference silicon wafer by utilizing parallel polarized light incident at the Brewster angle into the floating zone silicon wafer, and (c) a third step of calculating a substitutional carbon concentration ?C.sub.SC ! on the basis of the light transmission characteristic (I.sub.OBS) of the pulled silicon wafer measured during the first step and the light transmission characteristic (I.sub.O) of the floating zone silicon wafer measured during the second step, (d) a fourth step of comparing the substitutional carbon concentration ?C.sub.

Abstract: A scribe mark reader (10) uses a source of circularly polarized light and a holographic beam-shaping optical element (40) to uniformly illuminate an area of a substrate (20) that includes a scribe mark (18). Light incident on the substrate at a scribe mark is predominantly scattered, whereas light incident on the substrate at a processed area (30) of the wafer surface between the pits (28) of the scribe mark is predominantly specularly reflected. The phase-reversed, specularly reflected light from the processed area is blocked by a circular analyzer that passes light scattered from the scribe mark. Light passing the polarizer can then be used to form an image of the scribe mark. The intensity of the images formed are sufficiently consistent that the automatic gain control of the CCD camera can be used and the images formed can be readily interpreted by optical character recognition software.

Abstract: A device and method is provided for determining the degradation of oil after use of the same in an engine or the like. A test sample material is placed in a transparent container and various intensities of light are passed therethrough. A photovoltaic sensor senses the light polarized by the transparent container and the test sample and generates a first set of signals responsive thereto. The methodology is repeated with a sample of used automotive engine oil. The first and second set of signals are compared, and oil degradation is determined therefrom. Where the sensor detects and generates a signal only when the light intensity is equal to or less than the saturation intensity of the sensor, that is from the instant the light is first detected up until saturation of the sensor.

Abstract: A gel defect detection system for the optical inspection of defects in oriented transparent and translucent sheet. The system utilizes two polarizing filters with adjustable orientations so that the transmission axis is from about 70 degrees to about 110 degrees or from about 80 degrees to about 100 degrees. The system uses these polarization filters to help distinguish gel defects from the surrounding oriented sheet.

Abstract: A device for detecting defects (2, 3) in fibrous materials (4, 22) includes members (16, 17) for squeezing the material against a film (1), a separating member (24) downstream of the squeezing members for separating the fibrous material from the film, and an opto-electronic sensor (6) downstream of the separating member for imaging the film and defects. An image processing assembly (26, 44) is electrically connected to the output of the imaging assembly for sensing and counting the marks left on the film by the defects. A member (25) is provided for moving the film relative to the opto-electronic sensor. Various optical systems, particularly polarizers (9, 10), may be incorporated into the device.

Abstract: A fiber optic apparatus for controlling the polarization state of light, for connecting polarization sensitive devices, and for providing a controlled variable attenuation in a fiber optic system. The center portion of a strand of optical fiber is placed in a rotatable fiber squeezer and is squeezed to produce a birefringent medium having a birefringent axis in the direction of squeezing pressure and the magnitude of the birefringence is controlled by the amount of pressure imposed by the fiber squeezer on the fiber center portion. Rotating the squeezer causes the birefringent axis to change and hence changes the polarization of light passing through the fiber strand. A desired polarization state is obtained by controlling the squeezing pressure and the rotation angle of the fiber squeezer.

Abstract: In a photomask inspecting method, a photomask is inspected on the basis of the difference between the polarized state of elliptical light produced upon superposition of two linearly polarized light beams having orthogonal polarization directions and passing through two different optical paths and the polarized state of elliptical light produced when two linearly polarized light beams are superposed on each other after a target portion of a photomask is set in the optical path of one of the linearly polarized light beams. A photomask inspecting apparatus is also disclosed.

Abstract: A polarization-modulation scanning laser microscope includes a conventional laser scanning microscope, which has been improved by addition of: a polarization state generator; a polarization state analyzer; a photo-detector for receiving laser light transmitted though a sample; a signal demodulator providing two signals in response to the transmitted laser light, one of the signals being indicative of polarization orientation, and the other signal being indicative of magnitude of the transmitted polarized light. A relay interface toggles between the two signals provided by the signal demodulator and at least one other signal provided either by the photodiode of the laser scanning microscope, or by an external optical beam induced current, or both. A signal processing unit provides an image output to a display device.

Abstract: The presence and concentration of an optically active constituent of a fluid medium is determined in-situ by immersing in the fluid medium a probe constructed to pass plane polarized light through the fluid medium in first and second passes so as to induce an optical rotation to the plane of polarization. The light is analyzed after the second pass in a manner to provide a plurality of light components whose individual intensities are affected by the induced optical rotation. A light intensity ratio is determined for the individual light components and compared to light intensity ratios obtained from like fluid media having known concentrations of the optically active constituent therein to permit determination of the concentration of the optically active constituent.

Abstract: The invention related to a method for determining a silicon wafer in which the interstitial oxygen concentration of a pulled silicon wafer is calculated on the basis of a light transmission characteristic measured by utilizing parallel polarized light incident at the brewster angle into the pulled silicon wafer and a further light transmission characteristic measured by utilizing parallel polarized light incident at the brewster angle into the floating zone silicon wafer function as a reference silicon wafer. The interstitial oxygen concentration value of the pulled silicon wafer is compared with a reference value to determine a defect in pulled silicon wafer.

Abstract: A modulated Faraday rotation signal is produced by passing a linearly polarized laser beam through a semiconductor wafer sample in a modulated magnetic field that is induced in an electromagnet by a sine wave generator and driver coupled thereto. The rotation signal is normalized by dividing by a transmission signal produced by modulating the beam with a chopper that operates at a different frequency from the frequency of the driver. The result is a Faraday rotation measurement with high signal-to-noise ratio and compensation for laser drift in intensity.

Abstract: A non-mechanical optical switch is provided for alternately switching a monochromatic or quasi-monochromatic light beam along two optical paths. A polarizer polarizes light into a single, e.g., vertical component which is then rapidly modulated into vertical and horizontal components by a polarization modulator. A polarization beam splitter then reflects one of these components along one path and transmits the other along the second path. In the specific application of gas filter correlation radiometry, one path is directed through a vacuum cell and one path is directed through a gas correlation cell containing a desired gas. Reflecting mirrors cause these two paths to intersect at a second polarization beam splitter which reflects one component and transmits the other to recombine them into a polarization modulated beam which can be detected by an appropriate single sensor.

Abstract: A nulling optical bridge is disclosed herein for the measurement of the difference in the relative power of more than one light beam. The bridge can be used to precisely measure the change in reflectivity and/or transmissivity of a semiconductor device or metal. The bridge operates by splitting at least one illumination source into a number of beams wherein one of said beams is made to traverse the sample whose change in transmissivity and reflection characteristics is to be measured. A rotating polarizer is used to equate the intensity of the variable and nonvariable beams under feedback servo control from a photodetector. The incremental quantity of rotation of the polarizer can be calibrated to correspond to a number of characteristics of the sample.

Abstract: Two methods of determination of the chemical changes induced in a film of material such as photoresist that has been exposed to electromagnetic radiation. Two methods use measurement of polarized light reflected by the film mounted on a substrate to determine a real refractive index or a complex refractive index of the film. Two other methods use measurement of polarized light by the film mounted on a (partly) transparent substrate to determine a real refractive index or a complex refractive index of the film.

Abstract: An optical tooling method and apparatus uses a front lighted shadowgraphic technique to enhance visual contrast of reflected light. The apparatus includes an optical assembly including a fiducial mark, such as cross hairs, reflecting polarized light with a first polarization, a polarizing element backing the fiducial mark and a reflective surface backing the polarizing element for reflecting polarized light bypassing the fiducial mark and traveling through the polarizing element. The light reflected by the reflecting surface is directed through a second pass of the polarizing element toward the frontal direction with a polarization differing from the polarization of the light reflected by the fiducial mark. When used as a tooling target, the optical assembly may be mounted directly to a reference surface or may be secured in a mounting, such as a magnetic mounting.