Techniques and systems to achieve more accurate design alignment to an image by improved pixel-to-design alignment (PDA) target selection are disclosed. PDA targets in an image frame of a die can be biased to include a hotspot location in one of the PDA targets. The PDA targets can be evaluated for repetitive patterns by analyzing the uniqueness of the points used as the PDA targets.

The present invention may include acquiring a plurality of overlay metrology measurement signals from a plurality of metrology targets distributed across one or more fields of a wafer of a lot of wafers, determining a plurality of overlay estimates for each of the plurality of overlay metrology measurement signals using a plurality of overlay algorithms, generating a plurality of overlay estimate distributions, and generating a first plurality of quality metrics utilizing the generated plurality of overlay estimate distributions, wherein each quality metric corresponds with one overlay estimate distribution of the generated plurality of overlay estimate distributions, each quality metric a function of a width of a corresponding generated overlay estimate distribution, each quality metric further being a function of asymmetry present in an overlay metrology measurement signal from an associated metrology target.

Methods and systems for performing measurements of semiconductor structures based on high-brightness, Soft X-Ray (SXR) illumination over a small illumination spot size with a small physical footprint are presented herein. In one aspect, the focusing optics of an SXR based metrology system project an image of the illumination source onto a specimen under measurement with a demagnification of at least 1.25. In a further aspect, an illumination beam path from the x-ray illumination source to the specimen under measurement is less than 2 meters. In another aspect, SXR based measurements are performed with x-ray radiation in the soft x-ray region (i.e., 80-3000 eV). In some embodiments, SXR based measurements are performed at grazing angles of incidence in a range from near zero degrees to 90 degrees. In some embodiments, the illumination optics project an image of an illumination source onto a specimen under measurement with a demagnification of 50, or less.

Provided is an inspection method including providing a pattern layout including measurement points, generating a first measurement map including first measurement regions that overlap the measurement points and do not overlap each other in a two-dimensional plan view, providing preliminary measurement regions on the measurement points, producing a polygon by grouping ones of the preliminary measurement regions that overlap each other in the two-dimensional plan view, providing a second measurement region on a center of the polygon, selecting the second measurement region when all of the measurement points in the polygon overlap the second measurement region in the two-dimensional plan view, generating a second measurement map including the selected second measurement region, generating a third measurement map by using the first and second measurement maps, and inspecting patterns on a semiconductor substrate by using the third measurement map. The third measurement map includes the selected second measurement region and ones of the first measurement regions that do not overlap the selected second measurement region in the two-dimensional plan view.

A method and a system for detecting backscattered electrons in a multi-beam electron column.

The embodiments herein relate to defect inspection methods of semiconductor wafers during the manufacturing process. According to an aspect of the present disclosure, a defect inspection system is provided. The defect inspection system includes a first inspection system, pattern simulator software, and a second inspection system. The first inspection system is capable of determining a plurality of defect locations on an article. The pattern simulator software is capable of generating a set of simulated pattern features from the plurality of defect locations. The second inspection system is capable of providing a higher graphical resolution of defects than the first inspection at the defect locations corresponding to the set of simulated pattern features.

The present disclosure relates to a method for estimating heights of defects in a wafer. The method comprises creating an un-calibrated 3D model of a defect in a wafer, determining one or more attributes associated with the un-calibrated 3D model, transforming the un-calibrated 3D model to a calibrated 3D model, and estimating a height of the defect using the calibrated 3D model. Creating an un-calibrated 3D model corresponds to a defect present in a wafer based on a plurality of Scanning Electron Microscope (SEM) images of the defect. Transforming the un-calibrated 3D model to a calibrated 3D model uses a scaling factor corresponding to the determined one or more attributes associated with the un-calibrated 3D model. A height of the defect is estimated based on the calibrated 3D model of the defect.

A cathodoluminescence microscope and method are used to identify and classify dislocations within a semiconductor sample. At least two CL polarized images are concurrently obtained from the sample. The images are added together to obtain a total intensity image. A normalized difference of the images is taken to obtain a degree of polarization (DOP) image. The total intensity and DOP images are compared to differentiate between edge dislocations and screw dislocations within the sample. Edge dislocation density and screw dislocation density may then be calculated.

A transmission type small-angle scattering device of the present invention includes a goniometer 10 including a rotation arm 11. The rotation arm 11 is freely turnable around a θ-axis extending in a horizontal direction from an origin with a vertical arrangement state of the rotation arm being defined as the origin, and has a vertical arrangement structure in which an X-ray irradiation unit 20 is installed on a lower-side end portion of the rotation arm 11, and a two-dimensional X-ray detector 30 is installed on an upper-side end portion of the rotation arm 11 to form a vertical arrangement structure.

A tomographic method of determining a 3D map of a charge collection efficiency in a volume of investigation of a sample and an apparatus for performing the method. The sample has a charge carrier selecting structure and the method comprises the steps of: Arranging the sample in a beam path of a probe beam, wherein the probe beam propagates in a beam-direction which defines an axis in a laboratory frame coordinate system, Scanning the volume of investigation with an analyzing spot of the probe beam and simultaneously measuring the beam induced current and/or voltage, wherein a position of the sample arranged on a sample stage is defined by the coordinates z, y and r and a value of the beam induced current and/or voltage is determined for every position of the sample during the scanning action and Assigning every coordinate point (z, y, r) in the laboratory frame coordinate system, at which the analyzing spot of the probe beam hits the sample to a value of the beam induced current and/or voltage, which is measured for this point (z, y, r), reconstructing the 3D map of the charge collection efficiency by processing the values of the beam induced current and/or voltage determined for the coordinates (z, y, r) in the laboratory frame coordinate system with a tomographic image reconstruction algorithm so as to determine the 3D map of the charge collection efficiency in a coordinate system of the sample.