Abstract: A method for inspection includes irradiating, with a focused beam, a feature formed on a semiconductor wafer, the feature including a volume containing a first material and a cap made of a second material, different from the first material, that is formed over the volume. One or more detectors positioned at different angles relative to the feature are used to detect X-ray fluorescent photons that are emitted by the first material in response to the irradiating beam and pass through the cap before striking the detectors. Signals output by the one or more detectors at the different angles in response to the detected photons are processed in order to assess a quality of the cap.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having an epitaxial layer formed thereon, and sensing the X-rays that are diffracted from the sample while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including a diffraction peak and fringes due to the epitaxial layer. A characteristic of the fringes is analyzed in order to measure a relaxation of the epitaxial layer.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having multiple single-crystal layers, including at least a first layer and a second layer that is formed over and tilted relative to the first layer. The X-rays that are diffracted from each of the first and second layers are sensed simultaneously while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including at least a first diffraction peak due to the first layer and a second diffraction peak due to the second layer. The diffraction spectrum is analyzed so as to identify a characteristic of at least the second layer.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having an epitaxial layer formed thereon, and sensing the X-rays that are diffracted from the sample while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including a diffraction peak and fringes due to the epitaxial layer. A characteristic of the fringes is analyzed in order to measure a relaxation of the epitaxial layer.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having an epitaxial layer formed thereon, and sensing the X-rays that are diffracted from the sample while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including a diffraction peak and fringes due to the epitaxial layer. A characteristic of the fringes is analyzed in order to measure a relaxation of the epitaxial layer.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having multiple single-crystal layers, including at least a first layer and a second layer that is formed over and tilted relative to the first layer. The X-rays that are diffracted from each of the first and second layers are sensed simultaneously while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including at least a first diffraction peak due to the first layer and a second diffraction peak due to the second layer. The diffraction spectrum is analyzed so as to identify a characteristic of at least the second layer.

Abstract: A method for analysis includes directing a converging beam of X-rays toward a surface of a sample having an epitaxial layer formed thereon, and sensing the X-rays that are diffracted from the sample while resolving the sensed X-rays as a function of angle so as to generate a diffraction spectrum including a diffraction peak and fringes due to the epitaxial layer. A characteristic of the fringes is analyzed in order to measure a relaxation of the epitaxial layer.

Abstract: A method for inspection of a sample includes directing an excitation beam to impinge on an area of a planar sample that includes a feature having sidewalls perpendicular to a plane of the sample, the sidewalls having a thin film thereon. An intensity of X-ray fluorescence (XRF) emitted from the sample responsively to the excitation beam is measured, and a thickness of the thin film on the sidewalls is assessed based on the intensity. In another method, the width of recesses in a surface layer of a sample and the thickness of a material deposited in the recesses after polishing are assessed using XRF.

Abstract: A method for analyzing a sample includes directing one or more beams of X-rays to impinge on an area of a surface of the sample on which a layer of nano-particles of a selected element has been formed. Secondary X-ray radiation from the area is detected responsively to the one or more beams. A distribution of the nano-particles on the surface is characterized based on the detected radiation.

Abstract: A method for inspection includes irradiating a sample using an X-ray beam, which is focused so as to define a spot on a surface of the sample. At least one of the sample and the X-ray beam is shifted so as to scan the spot along a scan path that crosses a feature on the surface. Respective intensities of X-ray fluorescence emitted from the sample responsively to the X-ray beam are measured at a plurality of locations along the scan path, at which the spot has different, respective degrees of overlap with the feature. The intensities measured at the plurality of the locations are processed in order to compute an adjusted value of the emitted X-ray fluorescence over the scan path. A thickness of the feature is estimated based on the adjusted value.

Abstract: The computer-implemented method for inspection of a sample includes defining a plurality of locations on a surface of the sample, irradiating the surface at each of the locations with a beam of X-rays, and measuring an angular distribution of the X-rays that are emitted from the surface responsively to the beam, so as to produce a respective plurality of X-ray spectra. The X-ray spectra are analyzed to produce respective figures-of-merit indicative of a measurement quality of the X-ray spectra at the respective location. One or more locations are selected out of the plurality of locations responsively to the figures-of-merit, and a property of the sample is estimated using the X-ray spectra measured at the selected location.

Abstract: A method for X-ray analysis of a sample includes directing a beam of X-rays to impinge on a structure in the sample such that the X-rays are scattered from the structure in a pattern of stripes, and receiving the scattered X-rays using an array of detectors. A relative alignment between the sample and the array is adjusted so that the stripes are parallel to the detectors.

Abstract: Apparatus for analysis of a sample includes a radiation source, which is adapted to direct a first, converging beam of X-rays toward a surface of the sample and to direct a second, collimated beam of the X-rays toward the surface of the sample. A motion assembly moves the radiation source between a first source position, in which the X-rays are directed toward the surface of the sample at a grazing angle, and a second source position, in which the X-rays are directed toward the surface in a vicinity of a Bragg angle of the sample. A detector assembly senses the X-rays scattered from the sample as a function of angle while the radiation source is in either of the first and second source configurations and in either of the first and second source positions. A signal processor receives and processes output signals from the detector assembly so as to determine a characteristic of the sample.

Abstract: A computer-implemented method for inspection of a sample includes defining a plurality of locations on a surface of the sample, irradiating the surface at each of the locations with a beam of X-rays, and measuring an angular distribution of the X-rays that are emitted from the surface responsively to the beam, so as to produce a respective plurality of X-ray spectra. The X-ray spectra are analyzed to produce respective figures-of-merit indicative of a measurement quality of the X-ray spectra at the respective locations. One or more locations are selected out of the plurality of locations responsively to the figures-of-merit, and a property of the sample is estimated using the X-ray spectra measured at the selected locations.

Abstract: A method for inspection of a sample includes directing an excitation beam to impinge on an area of a planar sample that includes a feature having sidewalls perpendicular to a plane of the sample, the sidewalls having a thin film thereon. An intensity of X-ray fluorescence (XRF) emitted from the sample responsively to the excitation beam is measured, and a thickness of the thin film on the sidewalls is assessed based on the intensity. In another method, the width of recesses in a surface layer of a sample and the thickness of a material deposited in the recesses after polishing are assessed using XRF.

Abstract: A method for analyzing a sample includes directing one or more beams of X-rays to impinge on an area of a surface of the sample on which a layer of nano-particles of a selected element has been formed. Secondary X-ray radiation from the area is detected responsively to the one or more beams. A distribution of the nano-particles on the surface is characterized based on the detected radiation.

Abstract: A method for X-ray analysis of a sample includes directing a beam of X-rays to impinge on an area of a periodic feature on a surface of the sample and receiving the X-rays scattered from the surface in a reflection mode so as to detect a spectrum of diffraction in the scattered X-rays as a function of azimuth. The spectrum of diffraction is analyzed in order to determine a dimension of the feature.

Abstract: A method for inspection includes directing a beam of X-rays to impinge upon an area of a sample containing first and second features formed respectively in first and second thin film layers, which are overlaid on a surface of the sample. A pattern of the X-rays diffracted from the first and second features is detected and analyzed in order to assess an alignment of the first and second features.

Abstract: A method for inspection of a sample includes irradiating the sample with a beam of X-rays and measuring a distribution of the X-rays that are emitted from the sample responsively to the beam, thereby generating an X-ray spectrum. An assessment is made of an effect on the spectrum of a non-uniformity of the beam, and the spectrum is corrected responsively to the effect.

Abstract: A method for inspection includes irradiating a sample using an X-ray beam, which is focused so as to define a spot on a surface of the sample. At least one of the sample and the X-ray beam is shifted so as to scan the spot along a scan path that crosses a feature on the surface. Respective intensities of X-ray fluorescence emitted from the sample responsively to the X-ray beam are measured at a plurality of locations along the scan path, at which the spot has different, respective degrees of overlap with the feature. The intensities measured at the plurality of the locations are processed in order to compute an adjusted value of the emitted X-ray fluorescence over the scan path. A thickness of the feature is estimated based on the adjusted value.