Abstract: A method for evaluating a sample that includes an array of structural elements. The method includes obtaining a first small angle x-ray scattering (SAXS) pattern for a first angular relationship between the sample and an x-ray beam that exhibits a first collimation value and has a given cross-sectional area on a first side of the sample. A second SAXS pattern is obtained for a second angular relationship between the sample and the x-ray beam, while the x-ray beam exhibits a second collimation value that differs from the first collimation value while maintaining the given cross-sectional area of the x-ray beam on the first side of the sample, wherein the second angular relationship differs from the first angular relationship.

Abstract: A system for X-ray analysis, includes: (a) an X-ray analysis assembly configured to (i) direct an X-ray beam to impinge on a surface of a sample, and (ii) receive fluorescence radiation excited from the sample in response to the impinged X-ray beam, (b) a target assembly including measurement targets: placed in an optical path between the X-ray analysis assembly and the sample, and configured to move between (i) one or more first positions in which one or more of the measurement targets are positioned in the X-ray beam, and (ii) one or more second positions in which the optical path is unobstructed by the target assembly, and (c) a processor, configured to control movement of the target assembly between the first and second positions, for alternately, (i) monitoring properties of the X-ray beam using the measurement targets, and (ii) performing the X-ray analysis at a measurement site of the sample.

Abstract: An X-ray system includes, first and second X-ray channels (XCs), a spot sizer and a processor. The first XC is configured to: (i) direct a first X-ray beam for producing a spot on a surface of a sample, and (ii) produce a first signal responsively to a first X-ray radiation received from the surface. The spot sizer is positioned at a distance from the surface and is shaped and positioned to set the spot size by passing to the surface a portion of the first X-ray beam. The second XC is configured to: (i) direct a second X-ray beam to the surface, and (ii) produce a second signal responsively to a second X-ray radiation received from the surface, and the processor is configured to: (i) perform an analysis of the sample based on the first signal, and (ii) estimate the size of the spot based on the second signal.

Abstract: A method for X-ray measurement includes generating and directing an X-ray beam to a sample including at least first and second layers stacked on one another, the X-ray beam incident on a sample location at which the first and second layers include respective first and second high aspect ratio (HAR) structures. X-ray scatter profiles are measured, that are emitted from the sample location in response to the X-ray beam as a function of tilt angle between the sample and the X-ray beam. A shift is estimated, between the first and second layers and a characteristic tilt of the first and second layers, based on the X-ray scatter profiles measured as a function of the tilt angle.

Abstract: A method for evaluating an array of high aspect ratio (HAR) structures on a sample includes illuminating the sample with an x-ray beam along a first axis parallel to within two degrees to the HAR structures in the array and sensing a first pattern of small angle x-ray scattering (SAXS) scattered from the sample while illuminating the sample along the first axis. The sample is illuminated with the x-ray beam along a second axis that is oblique to the HAR structures in the array, and a second pattern of the SAXS scattered from the sample is sensed while illuminating the sample along the second axis. Information is extracted with respect to the HAR structures based on the first and second patterns.

Abstract: An X-ray tube that may include a cathode that is configured to generate an electron beam; an anode having a cavity that has an opening; wherein the anode is configured to receive the electron beam through the opening and to emit, through the opening, in response to the receiving of the electron beam, an X-ray beam from the opening; and electron optics that are configured to direct the electron beam towards the opening following a path that outside the cavity and in a vicinity of the opening, differs from a path of propagation the X-ray beam.

Abstract: An x-ray apparatus, that may include a mount that is configured to hold a sample; an x-ray source, that is configured to direct an x-ray beam toward a first side of the sample; a detector, positioned downstream to a second side of the sample, the detector is configured to detect, during a sample measurement period, at least a part of x-rays that have been transmitted through the sample; and an x-ray intensity detector that is positioned, during a beam intensity monitoring period at a measurement position that is located between the x-ray source and the first side of the sample, so as to detect at least a part of the x-ray beam before the x-ray beam reaches the sample.

Abstract: A method for X-ray scatterometry includes receiving a first distribution of an X-ray beam scattered from a sample. The first distribution exhibits asymmetry with respect to a reference axis. A correction is applied to the first distribution, so as to produce a second distribution in which a level of the asymmetry is reduced relative to the first distribution. One or more parameters of the sample are estimated based on the second distribution.

Abstract: An X-ray apparatus includes a mount, an X-ray source, a detector, an actuator, and a controller. The mount is configured to hold a sample. The X-ray source is configured to direct a beam of X-rays toward a first side of the sample. The detector is positioned on a second side of the sample, opposite the first side, so as to receive at least a portion of the X-rays that have been transmitted through the sample and to output signals indicative of an intensity of the received X-rays. The actuator is configured to scan the detector over a range of positions on the second side of the sample so as to measure the transmitted X-rays as a function of a scattering angle.

Abstract: An X-ray apparatus includes a mount, an X-ray source, a detector and a beam limiter. The mount is configured to hold a planar sample. The X-ray source is configured to direct a beam of X-rays toward a first side of the sample. The detector is positioned on a second side of the sample, opposite the first side, so as to receive at least a part of the X-rays that have been transmitted through the sample. The beam limiter is positioned on the first side of the sample so as to intercept the beam of the X-rays. The beam limiter includes first and second blades and first and second actuators. The first and second blades have respective first and second edges positioned in mutual proximity so as to define a slit, through which the beam of the X-rays will pass, at a distance smaller than 25 mm from the first side of the sample. The first and second actuators are configured to shift the first and second blades along respective, first and second translation axes so as to adjust a width of the slit.

Abstract: An X-ray apparatus includes a mount, an X-ray source, a detector, an optical gauge and a motor. The mount is configured to hold a planar sample having a first side, which is smooth, and a second side, which is opposite the first side and on which a pattern has been formed. The X-ray source is configured to direct a first beam of X-rays toward the first side of the sample. The detector is positioned on the second side of the sample so as to receive at least a part of the X-rays that have been transmitted through the sample and scattered from the pattern. The optical gauge is configured to direct a second beam of optical radiation toward the first side of the sample, to sense the optical radiation that is reflected from the first side of the sample, and to output a signal, in response to the sensed optical radiation, that is indicative of a position of the sample. The motor is configured to adjust an alignment between the detector and the sample in response to the signal.

Abstract: A system for X-ray topography, the system includes a source assembly, a detector assembly, a filter and a processor. The source assembly is configured to direct at least an X-ray beam to impinge, at an angle, on a first surface of a sample, the X-ray beam is divergent when impinging on the first surface. The detector assembly is configured to detect the X-ray beam that had entered the sample at the first surface, diffracted while passing through the sample and exited the sample at a second surface that is opposite to the first surface, and to produce an electrical signal in response to the detected X-ray beam. The filter is mounted between the source assembly and the first surface, and is configured to attenuate an intensity of a selected spectral portion of the X-ray beam. The processor is configured to detect one or more defects in the sample based on the electrical signal.

Abstract: A method for X-ray scatterometry includes receiving a first distribution of an X-ray beam scattered from a sample. The first distribution exhibits asymmetry with respect to a reference axis. A correction is applied to the first distribution, so as to produce a second distribution in which a level of the asymmetry is reduced relative to the first distribution. One or more parameters of the sample are estimated based on the second distribution.

Abstract: An apparatus for X-ray measurement, includes an X-ray source, an X-ray detector, an optical inclinometer, and a processor. The X-ray source is configured to generate and direct an X-ray beam to be incident at a grazing angle on a surface of a sample. The X-ray detector is configured to measure X-ray fluorescence emitted from the surface of the sample in response to being excited by the X-ray beam. The optical inclinometer is configured to measure an inclination of the surface of the sample. The processor is configured to calibrate the grazing angle of the X-ray beam based on the measured inclination, and to further fine-tune the grazing angle based on the X-ray fluorescence measured by the X-ray detector.