A method for evaluating images of a printed pattern. The method includes obtaining a first averaged image of the printed pattern, where the first averaged image is generated by averaging raw images of the printed pattern. The method also includes identifying one or more features of the first averaged image. The method further includes evaluating the first averaged image, using an image quality classification model and based at least on the one or more features. The evaluating includes determining, by the image quality classification model, whether the first averaged image satisfies a metric.

An aperture array for a multi-beam array system and a method of selecting a subset of a beam from a multi-beam array system are provided. The aperture array comprises an array body arranged proximate to a beam source. The array body comprises a plurality of apertures, at least two of the apertures having different geometries. The array body is movable, via an actuator, relative to an optical axis of the beam source, such that a subset of a beam from the beam source is selected based on the geometry of the aperture that is intersected by the optical axis.

Methods and systems for measuring semiconductor structures based on a trained scanning conditional measurement model are described herein. A scanning conditional model is trained based on Design Of Experiments (DOE) measurement data associated with known values of one or more parameters of interest and a set of perturbed values of the one or more parameters of interest. The trained conditional model minimizes the output of an error function characterizing the error between the known values of the perturbed values of the one or more parameters of interest for the given DOE measurement data. During inference, an error value associated with each candidate value of one or more parameters of interest is determined by the trained scanning conditional measurement model. The estimated value of the parameter of interest is the candidate value of the parameter of interest associated with the minimum error value.

According to the present invention, a desired one of multiple beams can be aligned with a small-diameter aperture quickly. A multi-electron beam inspection apparatus includes a beam selection aperture substrate including a first passage hole that passes all the multiple electron beams, a second passage hole through which one of the multiple electron beams is able to pass, a first slit, and a second slit not parallel to the first slit, an aperture moving unit moving the beam selection aperture substrate, a first detector detecting a current of a beam having passed through the first slit and a current of a beam having passed through the second slit, of the multiple electron beams, and a second detector detecting multiple secondary electron beams including reflected electrons, discharged from a substrate, due to application of the multiple electron beams, having passed through the first passage hole, to the substrate. The substrate is inspected based on an output signal from the second detector.

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.

A computer-based method for three-dimensional surface metrology of samples based on scanning electron microscopy and atomic force microscopy. The method includes: (i) using a scanning electron microscope (SEM) to obtain SEM data of a set of sites on a surface of a sample; (ii) using an atomic force microscope (AFM) to measure vertical parameters of sites in a calibration subset of the set; (iii) calibrating an algorithm, configured to estimate a vertical parameter of a site when SEM data of the site are fed as inputs, by determining free parameters of the algorithm, such that residuals between the algorithm-estimated vertical parameters and the AFM-measured vertical parameters are about minimized; and (iv) using the calibrated algorithm to estimate vertical parameters of the sites in the complement to the calibration subset.

The present invention provides a charged particle beam device with which optimal parameters for the device can be effectively derived in a short time period. This charged particle beam device comprises: an electron gun (1) that irradiates a sample (10) with an electron beam (2); an image processing unit (901) that acquires an image of the sample (10) from a signal (12) generated by the sample (10) due to the electron beam (2); a database (604) that holds correspondence between a first parameter that is an optical condition, a second parameter that is a value pertaining to device performance, and a third parameter that is information pertaining to the device configuration, and stores a plurality of analysis values and measurement values; and a learning machine (605) that searches the database (604) and derives a first parameter that satisfies a target value of the second parameter.

A method for measuring an element concentration of a material includes: a material sample is irradiated with first electromagnetic waves; second electromagnetic waves radiated by the material sample are obtained under the action of the first electromagnetic waves; material property parameters of the material sample are determined by detecting the second electromagnetic waves; and an element concentration of the material sample is determined according to the material property parameters.

A method of generating a correction line indicating a relationship between an amount of deviation of an edge of a wafer pattern from an edge of a reference pattern and a width of a space adjacent to the edge of the reference pattern, includes: creating an appearance-frequency graph of widths of spaces adjacent to reference patterns located within a designated area; obtaining images of wafer patterns corresponding to a plurality of space widths shown in the appearance-frequency graph; calculating amounts of deviation between edges of the wafer patterns on the images and edges of corresponding reference patterns; plotting a plurality of data points on a coordinate system, the plurality of data points being specified by the plurality of space widths and the amounts of deviation; and generating a correction line from the plurality of data points on the coordinate system.

A metrology method for use in determining one or more parameters of a patterned structure, the method including providing raw measured TEM image data, TEM.sub.meas, data indicative of a TEM measurement mode, and predetermined simulated TEM image data including data indicative of one or more simulated TEM images of a structure similar to the patterned structure under measurements and a simulated weight map including weights assigned to different regions in the simulated TEM image corresponding to different features of the patterned structure, performing a fitting procedure between the raw measured TEM image data and the predetermined simulated TEM image data and determining one or more parameters of the structure from the simulated TEM image data corresponding to a best fit condition.