213 results about "Reflectivity measurement" patented technology

A mobile soil mapping system includes an implement for traversing a field to be mapped, and a reflectance module carried by the implement for collecting spectroscopic measurements of soil in the field. The reflectance module has a light source, an optical receiver for transmitting light to a spectrometer, and a shutter system that alters the optical path between the light source and the optical receiver. The shutter system allows the system to automatically collect a dark reference measurement and a known reference material measurement at timed intervals to compensate for drift of the spectrometer and the light source. A self-cleaning window on the reflectance module has a lower surface maintained in firm contact with the soil during operation. External reference blocks are used to calibrate the system to ensure standardized, repeatable data. Additional sensors are carried by the implement to collect other soil data, such as electrical conductivity and temperature.

The present invention provides a high-speed Quantum Efficiency (QE) measurement device that includes at least one device under test (DUT), at least one conditioned light source with a less than 50 nm bandwidth, where a portion of the conditioned light source is monitored. Delivery optics are provided to direct the conditioned light to the DUT, a controller drives the conditioned light source in a time dependent operation, and at least one reflectance measurement assembly receives a portion of the conditioned light reflected from the DUT. A time-resolved measurement device includes a current measurement device and/or a voltage measurement device disposed to resolve a current and/or voltage generated in the DUT by each conditioned light source, where a sufficiently programmed computer determines and outputs a QE value for each DUT according to an incident intensity of at least one wavelength of from the conditioned light source and the time-resolved measurement.

A method of correcting reflectivity measurements performed by a radar, such as a weather radar, includes a reflectivity measurement being associated with a resolution volume. The method includes acquiring the reflectivity measurement Z_m corresponding to the current resolution volume, estimating the attenuation k_c introduced by the cloud droplets, said estimating being carried out by using an average vertical profile of the cloud liquid water content, estimating the attenuation k_g,O2 introduced by dioxygen, estimating the attenuation k_g,H2O introduced by the water vapor, determining the total specific attenuation k of the non-detectable components taking into account the attenuation k_c, the attenuation k_g,O2 and the attenuation k_g,H2O estimated in the preceding steps, and correcting the measured reflectivity taking into account the estimated total specific attenuation k. The method may be implemented by an onboard weather radar.

A characteristic of a surface is measured by illuminating the surface with optical radiation over a wide angle and receiving radiation reflected from the surface over an angle that depends on the extend of the illumination angle. An emissivity measurement is made for the surface, and, alternatively, if a reflectivity measurement is made, it becomes more accurate. One application is to measure the thickness of a layer or layers, either a layer made of transparent material or a metal layer. A one or multiple wavelength technique allow very precise measurements of layer thickness. Noise from ambient radiation is minimized by modulating the radiation source at a frequency where such noise is a minimum or non-existent. The measurements may be made during processing of the surface in order to allow precise control of processing semiconductor wafers, flat panel displays, or other articles. A principal application is in situ monitoring of film thickness reduction by chemical-mechanical-polishing (CMP).

The invention relates to a method for comprehensively measuring reflectivity, which comprises the following steps: dividing continuous incident laser beams into a reference beam and a detection beam, wherein the reference beam is focused on a photoelectric detector for direct detection and the detection beam is injected into an optical resonant cavity; using a cavity ring-down technology to measure an optical element with reflectivity more than 99%, respectively measuring a ring-down time tau 0 of an original optical resonant cavity output signal and a ring-down time tau 1 of the measured optical resonant cavity output signal after an optical element to be measured is added, and calculating the reflectivity R of the optical element to be measured; using the spectrophotometry to measure the reflectivity of the optical element to be measured when the R value is less than 99%; moving away an output cavity mirror; focusing detecting light reflected by a measuring mirror on the photoelectric detector for detecting while recording a light intensity signal ratio of the detection beam to the reference beam; and calibrating to further obtain the reflectivity R of the optical element to be measured. The device for measuring reflectivity can be used for measuring optical elements with any reflectivity and also can be used for realizing the high-resolution two-dimensional imaging of the reflectivity distribution of a large-aperture optical element.

Facial recognition can be used to determine whether or not a user has access privileges to a device such as a smartphone. It may be possible to spoof an authenticated user's image using a picture of the user. Implementations disclosed herein utilize time of flight and/or reflectivity measurements of an authenticated user to compare to such values obtained for an image of an object. If the time of flight distance and/or reflectivity distance for the object match a measured distance, then the person (i.e., object) may be granted access to the device.

The invention discloses a measurement device and a measurement method of optical parameters of a dielectric film. The measurement device comprises a sample platform assembly for placing a sample, a refractive index and thickness measurement assembly, a transmissivity and refractive index measurement assembly and a controller, wherein the refractive index and thickness measurement assembly is formed by a laser light source assembly, a polarizer, a semi-permeability and semi-reflection mirror, a circular hole diaphragm, an automatic-collimation detector and a measurement detector; and the transmissivity and refractive index measurement assembly is formed by a white-light light source, a collimation lens set which is connected with the white-light light source and is used for a collimation light path, an integrating sphere which is used for collecting light transmitted or reflected by the sample placed on the sample platform assembly, and a spectrograph connected with the integrating sphere. The measurement device disclosed by the invention has the advantages that the refractive index and thickness measurement assembly can measure the reflective index and the thickness of the sample, and the transmissivity and refractive index measurement assembly can measure the transmissivity and the refractive index of the sample, so that the measurement of various optical parameters is realized and the measurement precision is high.

A system and method for calibrating a pyrometer used in temperature detection in a chemical vapor deposition system is provided. A calibration wafer with a reference region including a metal such as Al or Ag for forming a eutectic, and an exposed non-reference region without such a metal, are provided. Reflectivity measurements are taken from the reference region, and temperature measurements are taken from the non-reference region, over a range of temperatures including a known melting point for the metal eutectic. The pyrometer is calibrated based on the correlation of the known eutectic melting point with the change in reflectivity data obtained in the reference region, in light of the temperature data obtained from the non-reference region.

A multi-patterning method of manufacturing a patterned wafer provides test structures designed to enhance overlay error measurement sensitivity for monitoring and process control. One or more patterns are overlaid on a first pattern, each of a given pitch, with the elements interleaved. Test structure is formed with elements of the overlaid patterns spaced away from respective mid-positions more closely toward elements of the first pattern. In some embodiments, test structure elements of the second pattern are overlaid midway between mid-positions of elements of the first pattern and measured by scatterometry. In other embodiments, test structure elements of the second pattern are overlaid at a slightly different pitch than the elements of the first pattern and measured by reflectivity. Measurements are compared with library measurements to identify the error, which may be fed back to control the patterning process. The multi-patterning may be formed by LELE, LLE, LFLE, or other methods.

A method for measuring reflectivity of microwave absorption material applies network analyzer being set with test cable, switching over connector, coaxial air line and metal short circuit as well as being able to directly measure s parameter of microwave component as measuring system to carry out reflectivity measurement on microwave absorption material sample of concentric ring form in matching to size of coaxial air line.

A method and apparatus for in-situ metrology of a workpiece disposed in a vacuum processing chamber. The apparatus may include an optical assembly external to the processing chamber configured to focus a relatively large optical spot over a relatively large working distance to acquire a TE and TM spectra from a periodic array on the workpiece. The workpiece may be disposed in the processing chamber with an arbitrary orientation which is first determined via a reflectance measurement. TE and/or TM spectra may then be acquired by initiating a periodic triggering of a flash lamp based on the determined workpiece orientation to account for variation in placement of the workpiece within the processing chamber. The periodic array from which spectra are collected may be a memory array being fabricated in a semiconductor wafer.

A method of producing a finish for a selected wood substrate, wherein the finish provides the selected wood substrate with a color that matches the color of a target object. In accordance with the method, calculations are performed to determine the quantities of at least one group of colorants required to produce a semitransparent wood stain from a vehicle, wherein when the semitransparent wood stain is applied to the selected wood substrate, the selected wood substrate will have a color that matches the target object. The calculations are performed using reflectance measurements of the target object obtained using a spectrophotometer and previously obtained spectral data of the colorants as applied to at least one type of wood. The colorants used to form the semitransparent wood stain do not include a white colorant.

A method of error compensation in a chromatic point sensor (CPS) reduces errors associated with varying workpiece spectral reflectivity. The errors are associated with a distance-independent profile component of the CPS measurement signals. Workpiece spectral reflectivity may be characterized using known spectral reflectivity for a workpiece material, or by measuring the workpiece spectral reflectivity using the CPS system. CPS spectral reflectivity measurement may comprise scanning the CPS optical pen to a plurality of distances relative to a workpiece surface and determining a distance-independent composite spectral profile from a plurality of resulting wavelength peaks. By comparing the distance-independent composite spectral profile obtained from a workpiece with that corresponding to the CPS distance calibration procedure, the contribution of the reflectivity characteristics of the workpiece will be indicated in the differences between the profiles, and potential CPS position errors due to varying workpiece reflectivity characteristics may be calculated and/or compensated.

The invention discloses a method for measuring the reflectivity of a dual-wavelength high reflecting mirror. The method comprises the following steps: injecting the continuous lasers of two different wavelengths with periodically modulated light intensity into a stable initial optical resonance cavity composed of two or three dual-wavelength high reflecting mirrors at the same time; when the amplitude of the output signal of the initial optical resonance cavity is higher than a set threshold, cutting off the incident laser beam and recording the cavity ring-down signal; or recording the cavity ring-down signal at the falling edge of a modulation signal, and obtaining the ring-down time [tau]01 and [tau]02 of the initial optical resonance cavity at the two laser wavelengths by use of a synchronous measurement method, spectral detection method or alternate measurement method, and calculating the average reflectivity R01 and R02 of a cavity mirror at the two wavelengths; similarly, adding a dual-wavelength high reflecting mirror to be measured into the initial optical resonance cavity according to the using angle so as to form a stable test optical resonance cavity; obtaining the ring-down time [tau]01 and [tau]02 of the test optical resonance cavity at the two laser wavelengths by use of a synchronous measurement method, spectral detection method or alternate measurement method; and obtaining the reflectivity R1 and R2 of the dual-wavelength high reflecting mirror to be measured at the two wavelengths.

The invention discloses a method and a device for measuring a nano film. The method for measuring the nano film comprises the following steps of acquiring a transmittance measurement value or a reflectivity measurement value of the nano film; acquiring ellipsometry parameters of the nano film; estimating the thickness of the nano film, obtaining a pseudo optical constant of the nano film according to the ellipsometry parameter and the estimated thickness; obtaining a transmittance calculation value or a reflectivity calculation value of the nano film according to the estimated thickness and the pseudo optical constant; executing the error comparison for the transmittance measurement value or the reflectivity measurement value with the transmittance calculation value or the reflectivity calculation value, and utilizing the estimated thickness and the pseudo optical constant corresponding to the minimal error value as the thickness and optical constant of the nano film. By adopting the transmittance or reflectivity and the ellipsometry method to assist the analysis, the pseudo optical constant is introduced, and the data is processed by adopting a fitting algorithm and an iteration algorithm, so that the optical constant and thickness of a film sample can be precisely measured.

Methods and apparatus for heat-treating a workpiece are disclosed. An illustrative method includes measuring deformation of a workpiece during heat-treating thereof, and taking an action in relation to the heat-treating of the workpiece, in response to the measuring of the deformation of the workpiece. The workpiece may include a semiconductor wafer. Taking an action may include applying a deformation correction to a temperature or reflectivity measurement of the wafer during thermal processing, or may include modifying the heat-treating of the wafer, for example.

Preferred embodiments of a semiconductor wafer temperature measurement method take advantage of the tight control of the surface conditions and temperature of a hot susceptor, which tight control provides known and reproducible radiation emissions from the hot susceptor. The known amount of radiation emitted by the hot susceptor is employed as a stable radiation source for making precise reflectance and emission measurements of the semiconductor wafer.

A system and method of correcting reflectance comprises determining a reflectance constant for a test product at a first wavelength for which reflectance does not substantially change with the presence of a test substance, with the test product loaded with the test substance, determining a reflectance at a second wavelength for which signal-to-noise ratio is maximized and determining a measured reflectance at the first wavelength, and determining a corrected reflectance as the product of the reflectance with a ratio of the reflectance constant to the measured reflectance.

A reflectometer calibration technique is provided that may include the use of two calibration samples in the calibration process. Further, the technique allows for calibration even in the presence of variations between the actual and assumed properties of at least one or more of the calibration samples. In addition, the technique utilizes a ratio of the measurements from the first and second calibration samples to determine the actual properties of at least one of the calibration samples. The ratio may be a ratio of the intensity reflected from the first and second calibration samples. The samples may exhibit relatively different reflective properties at the desired wavelengths. In such a technique the reflectance data of each sample may then be considered relatively decoupled from the other and actual properties of one or more of the calibration samples may be calculated. The determined actual properties may then be utilized to assist calibration of the reflectometer.