Abstract: A composite metrology tool, measures basic optical parameters of thin films (e.g., thickness, index of refraction, and birefringence) and stress (e.g., wafer displacements, such as bow and warp). These measurements are combined (e.g. in a processor) using optimization techniques to yield accurate overall information of the wafer parameters.

Abstract: A method is disclosed for evaluating isolated and aperiodic structure on a semiconductor sample. A probe beam from a coherent laser source is focused onto the structure in a manner to create a spread of angles incidence. The reflected light is monitored with an array detector. The intensity or polarization state of the reflected beam as a function of radial position within the beam is measured. Each measurement includes both specularly reflected light as well as light that has been scattered from the aperiodic structure into that detection position. The resulting output is evaluated using an aperiodic analysis to determine the geometry of the structure.

Abstract: An method and apparatus are disclosed for accurately and repeatably determining the thickness of a thin film on a substrate. A rotating compensator ellipsometer is used which generates both 2&ohgr; and 4&ohgr; output signals. The. 4&ohgr; omega signal is used to provide an indication of the temperature of the sample. This information is used to correct the analysis of the thin film based on the 2&ohgr; signal. These two different signals generated by a single device provide independent measurements of temperature and thickness and can be used to accurately analyze a sample whose temperature is unknown.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: This invention provides a measurement device that includes both an X-ray reflectometer and a thermal or plasma wave measurement module for determining the characteristics of a sample. Preferably, these two measurement modules are combined into a unitary apparatus and arranged to be able to take measurements at the same location on the wafer. A processor will receive data from both modules and combine that data to resolve ambiguities about the characteristics of the sample. The processor can be part of the device or separate therefrom as long as the measurement data is transferred to the processor.

Abstract: This invention provides a measurement device that includes both an X-ray reflectometer and a thermal or plasma wave measurement module for determining the characteristics of a sample. Preferably, these two measurement modules are combined into a unitary apparatus and arranged to be able to take measurements at the same location on the wafer. A processor will receive data from both modules and combine that data to resolve ambiguities about the characteristics of the sample. The processor can be part of the device or separate therefrom as long as the measurement data is transferred to the processor.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: This invention provides a measurement device that includes both an X-ray reflectometer and a thermal or plasma wave measurement module for determining the characteristics of a sample. Preferably, these two measurement modules are combined into a unitary apparatus and arranged to be able to take measurements at the same location on the wafer. A processor will receive data from both modules and combine that data to resolve ambiguities about the characteristics of the sample. The processor can be part of the device or separate therefrom as long as the measurement data is transferred to the processor.

Abstract: A method and apparatus are disclosed for evaluating relatively small periodic structures formed on semiconductor samples. In this approach, a light source generates a probe beam which is directed to the sample. In one preferred embodiment, an incoherent light source is used. A lens is used to focus the probe beam on the sample in a manner so that rays within the probe beam create a spread of angles of incidence. The size of the probe beam spot on the sample is larger than the spacing between the features of the periodic structure so some of the light is scattered from the structure. A detector is provided for monitoring the reflected and scattered light. The detector includes multiple detector elements arranged so that multiple output signals are generated simultaneously and correspond to multiple angles of incidence. The output signals are supplied to a processor which analyzes the signals according to a scattering model which permits evaluation of the geometry of the periodic structure.

Abstract: A method and apparatus are disclosed for evaluating relatively small periodic structures formed on semiconductor samples. In this approach, a light source generates a probe beam which is directed to the sample. In one preferred embodiment, an incoherent light source is used. A lens is used to focus the probe beam on the sample in a manner so that rays within the probe beam create a spread of angles of incidence. The size of the probe beam spot on the sample is larger than the spacing between the features of the periodic structure so some of the light is scattered from the structure. A detector is provided for monitoring the reflected and scattered light. The detector includes multiple detector elements arranged so that multiple output signals are generated simultaneously and correspond to multiple angles of incidence. The output signals are supplied to a processor which analyzes the signals according to a scattering model which permits evaluation of the geometry of the periodic structure.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: This invention provides a measurement device that includes both an X-ray reflectometer and a thermal or plasma wave measurement module for determining the characteristics of a sample. Preferably, these two measurement modules are combined into a unitary apparatus and arranged to be able to take measurements at the same location on the wafer. A processor will receive data from both modules and combine that data to resolve ambiguities about the characteristics of the sample. The processor can be part of the device or separate therefrom as long as the measurement data is transferred to the processor.

Abstract: This invention provides a measurement device that includes both an X-ray reflectometer and a thermal or plasma wave measurement module for determining the characteristics of a sample. Preferably, these two measurement modules are combined into a unitary apparatus and arranged to be able to take measurements at the same location on the wafer. A processor will receive data from both modules and combine that data to resolve ambiguities about the characteristics of the sample. The processor can be part of the device or separate therefrom as long as the measurement data is transferred to the processor.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: An optical measurement system is disclosed for evaluating samples with multi-layer thin film stacks. The optical measurement system includes a reference ellipsometer and one or more non-contact optical measurement devices. The reference ellipsometer is used to calibrate the other optical measurement devices. Once calibration is completed, the system can be used to analyze multi-layer thin film stacks. In particular, the reference ellipsometer provides a measurement which can be used to determine the total optical thickness of the stack. Using that information coupled with the measurements made by the other optical measurement devices, more accurate information about individual layers can be obtained.

Abstract: An apparatus for the non-invasive analysis of non-homogeneous samples is disclosed. The apparatus is particularly suited for analyzing biological samples having different constituents. An intensity modulated light beam is used to preferentially heat a selected constituent in the sample. This periodic heating will create thermal waves in the sample. A probe beam is directed to interact with the sample in the region which has been periodically heated. A phase synchronous detector is used to monitor the periodic changes in the probe beam caused by the thermal waves in the sample. In the preferred embodiment for monitoring blood glucose levels, the wavelength of the modulated light beam is selected to be absorbed in the hemoglobin of the red blood cells. The modulation frequency of the light beam is selected to set the thermal diffusion length of the thermal waves to permit interaction with the glucose molecules in the blood plasma.

Abstract: An optical measurement device is disclosed for evaluating the parameters of a sample. The device includes a polychromatic source for generating a probe beam. The probe beam is focused on the sample surface. Individual rays within the reflected probe beam are simultaneously analyzed as a function of the position within the beam to provide information at multiple wavelengths. A filter, dispersion element and a two-dimensional photodetector array may be used so that the beam may be simultaneously analyzed at multiple angles of incidence and at multiple wavelengths. A variable image filter is also disclosed which allows a selection to be made as to the size of the area of the sample to be evaluated.

Abstract: An optical measurement device is disclosed for evaluating the parameters of a sample. The device includes a polychromatic source for generating a probe beam. The probe beam is focused on the sample surface. Individual rays within the reflected probe beam are simultaneously analyzed as a function of the position within the beam to provide information at multiple wavelengths. A filter, dispersion element and a two-dimensional photodetector array may be used so that the beam may be simultaneously analyzed at multiple angles of incidence and at multiple wavelengths. A variable image filter is also disclosed which allows a selection to be made as to the size of the area of the sample to be evaluated.

Abstract: An apparatus is disclosed for evaluating thermal and electrical characteristics of a sample. An intensity modulated pump beam is focused onto the surface of a sample at one spot. A non-modulated probe beam is focused onto the sample at a second spot, spaced laterally and vertically from the first spot. The distance between the two spots is at least two microns. The modulated power of the reflected probe beam that is in phase with the pump beam modulation frequency is monitored to provide information about the characteristics of the sample. The apparatus is particularly useful in evaluating the integrity of metal lines and vias in a semiconductor sample.