Disclosed is a metrology device (1600) configured to produce measurement illumination comprising a plurality of illumination beams, each of said illumination beams being spatially incoherent or pseudo-spatially incoherent and comprising multiple pupil points in an illumination pupil of the metrology device. Each pupil point in each one of said plurality of illumination beams has a corresponding pupil point in at least one of the other illumination beams of said plurality of illumination beams thereby defining multiple sets of corresponding pupil points, and the pupil points of each set of corresponding pupil points are spatially coherent with respect to each other.

A method of hot spot ranking for a patterning process. The method includes obtaining (i) a set of hot spots of a patterning process, (ii) measured values of one or more parameters of the patterning process corresponding to the set of hot spots, and (ii) simulated values of the one or more parameters of the patterning process corresponding to the set of hot spots; determining a measurement feedback based on the measured values and the simulated values of the one or more parameters of the patterning process; and determining, via simulation of a process model of the patterning process, a ranking of a hot spot within the set of hot spots based on the measurement feedback.

Disclosed are a repairable photomask structure and extreme ultraviolet (EUV) photolithography methods. The structure includes a multilayer stack, a protective layer above the stack and a light absorber layer above the protective layer. The stack includes alternating layers of high and low atomic number materials and a selected one of the high atomic number material layers is different from the others such that it functions as an etch stop layer. This configuration allows the photomask structure to be repaired if/when defects are detected near exposed surfaces of the multilayer stack following light absorber layer patterning. For example, when a defect is detected near an exposed surface of the stack in a specific opening in the light absorber layer, the opening can be selectively extended down to the etch stop layer or all the openings can be extended down to the etch stop layer in order to remove that defect.

A method and apparatus for use in surface delayering for fault isolation and defect localization of a sample work piece is provided. More particularly, a method and apparatus for mechanically peeling of one or more layers from the sample in a rapid, controlled, and accurate manner is provided. A programmable actuator includes a delayering probe tip with a cutting edge that is shaped to quickly and accurately peel away a layer of material from a sample. The cutting face of the delayering probe tip is configured so that each peeling step peels away an area of material having a linear dimension substantially equal to the linear dimension of the delayering probe tip cutting face. The surface delayering may take place inside a vacuum chamber so that the target area of the sample can be observed in-situ with FIB/SEM imaging.

A die screening system may receive die-resolved metrology data for a population of dies on one or more samples from the one or more in-line metrology tools after one or more fabrication steps, where the die-resolved metrology data includes images generated using one or more measurement configurations of the one or more in-line metrology tools. In this way, the die-resolved metrology data provides many measurement channels per die, where a particular measurement channel includes data from a particular pixel of a particular image. The controller may then generate screening data for the population of dies from the die-resolved metrology data, where the screening data includes a subset of the plurality of measurement channels of the die-resolved metrology data, and screen the plurality of dies into two or more disposition classes including at least outlier dies based on variability in the screening data.

An evaluation apparatus that evaluates a composition formed on a substrate by forming processing is provided. The apparatus comprises an obtaining device that obtains an image including the composition by the forming processing, and a processing device that processes the image for the evaluation. The processing device outputs a feature of each of one or more abnormalities in the image according to an inference model, obtains information regarding a formation region on the substrate where the composition has been formed, determines the kind of each of the abnormalities based on the output feature of each of the abnormalities and a relationship between the information and a position and a size of the abnormality, and makes, based on a result of the determination, final determination as to whether the image is a normal image or an image including an abnormality.

A mode control system and method for controlling an output mode of a broadband radiation source including a photonic crystal fiber (PCF). The mode control system includes at least one detection unit configured to measure one or more parameters of radiation emitted from the broadband radiation source to generate measurement data, and a processing unit configured to evaluate mode purity of the radiation emitted from the broadband radiation source, from the measurement data. Based on the evaluation, the mode control system is configured to generate a control signal for optimization of one or more pump coupling conditions of the broadband radiation source. The one or more pump coupling conditions relate to the coupling of a pump laser beam with respect to a fiber core of the photonic crystal fiber.

Disclosed is a method and associated inspection apparatus for measuring a characteristic of interest relating to a structure on a substrate. The inspection apparatus uses measurement radiation comprising a plurality of wavelengths. The method comprises performing a plurality of measurement acquisitions of said structure, each measurement acquisition being performed using measurement radiation comprising a different subset of the plurality of wavelengths, to obtain a plurality of multiplexed measurement signals. The plurality of multiplexed measurement signals are subsequently de-multiplexed into signal components according to each of said plurality of wavelengths, to obtain a plurality of de-multiplexed measurement signals which are separated according to wavelength.

A defect pattern grouping method is disclosed. The defect pattern grouping method comprises obtaining a first polygon that represents a first defect from an image of a sample, comparing the first polygon with a set of one or more representative polygons of a defect-pattern collection, and grouping the first polygon with any one or more representative polygons identified based on the comparison.

In an inspection apparatus, a target on the surface is illuminated with illuminating radiation that comprises first and second illuminating components. The illuminating components form one or more periodic illuminating patterns on the surface. A plurality of scattered radiation patterns formed by the illuminating radiation after scattering by the target is captured at a detector for a number of values of a controllable characteristic of at least one of the illuminating components. The captured radiation is then used to reconstruct data describing the target.