In a method to obtain information to control a manufacturing process for a stacked semiconductor device including several semiconductor layers requiring electrically interconnection, sample data of a semiconductor device sample to be inspected are provided. An X-ray imaging scan of the sample obtaining respective X-ray imaging data is performed. Sample detail information of sample details of the sample are gathered from the X-ray imaging data which are vital for the manufacturing process. Multiple Regions of Interest (ROIs) are identified from the gathered sample detail information by processing data resulting from an ROI identification model, such ROI identification model being previously trained in a machine learning process. Metrology data are extracted from the identified ROIs by processing data resulting from a metrology model, such metrology model being previously trained in a machine learning process. With such method, a process time to obtain the required information to control the manufacturing process can be reduced.

Disclosed is a method of updating of a first model by training a second model, the first model relating to a first process range and trained using a first set of measurement signals relating to a first set of structures. The method comprises: obtaining a second set of measurement signals, the second set of measurement signals relating to a second set of structures comprising said first set of structures or a subset thereof; and training the second model using said second set of measurement signals and corresponding reference values for the parameter of interest as training data. The training comprises optimizing a cost function in terms of the second model while constraining the second model to infer values for the parameter of interest from the first set of measurement signals.

An illumination mode selector for use in an illumination branch of an optical metrology tool, and an associated optical metrology tool. The illumination mode selector includes a plurality of illumination apertures; and at least one polarization-changing optical element. Each of the illumination apertures and each of the at least one polarization-changing optical element are individually switchable into an illumination path of the optical metrology tool.

A multi-column metrology tool may include two or more measurement columns distributed along a column direction, where the two or more measurement columns simultaneously probe two or more measurement regions on a sample including metrology targets. A measurement column may include an illumination sub-system to direct illumination to the sample, a collection sub-system including a collection lens to collect measurement signals from the sample and direct it to one or more detectors, and a column-positioning sub-system to adjust a position of the collection lens. A measurement region of a measurement column may be defined by a field of view of the collection lens and a range of the positioning system in the lateral plane. The tool may further include a sample-positioning sub-system to scan the sample along a scan path different than the column direction to position metrology targets within the measurement regions of the measurement columns for measurements.

An apparatus includes a control unit configured to control an adjustment unit for adjusting imaging characteristics of an optical system. In a period spanning a plurality of lots, the control unit measures imaging characteristics of the optical system, and decides a prediction coefficient in a prediction formula to fit the prediction formula to measurement data obtained by the measurement in the period spanning the plurality of lots. The prediction formula is a polynomial function including a term representing a change in measurement value of the imaging characteristics caused by changing at least one of an illumination mode and an original between lots. The control unit decides the term of the polynomial function such that a fitting residual falls within an allowable range.

A method for performing a lithographic apparatus setup calibration and/or drift correction for a specific lithographic apparatus of a population of lithographic apparatuses to be used in a manufacturing process for manufacturing an integrated circuit extending across a plurality of layers on a substrate. The method includes determining a spatial error distribution of an apparatus parameter across spatial coordinates on the substrate for each lithographic apparatus of the population of lithographic apparatuses and/or each layer of the plurality of layers; determining a reference distribution by aggregating each of the spatial error distributions to optimize the reference distribution such that a spatial distribution of a parameter of interest of the manufacturing process is co-optimized across the population of lithographic apparatuses and/or plurality of layers; and using the reference distribution as a target distribution for the apparatus parameter for each lithographic apparatus and/or layer.

Disclosed is a method of determining a correction for a measurement of at least one target on a substrate, the target comprising one or more parameter of interest sensitive sub-targets which are each sensitive to a parameter of interest and one or more parameter of interest insensitive sub-targets which are substantially less sensitive or insensitive to the parameter of interest, the method comprising. The method comprises obtaining a respective first measurement parameter value relating to each of said one or more parameter of interest sensitive sub-targets; obtaining a respective second measurement parameter value relating to each of said one or more parameter of interest insensitive sub-targets; and determining a correction for each said first measurement parameter value using said second measurement parameter values and/or detecting the presence of an effect likely to impact accuracy of first measurement parameter values from said second measurement parameter values.

Disclosed is an imaging method comprising obtaining a set of primary deconvolution kernels or a set of impulse responses relating to an optical system used to capture said image; obtaining said image signal, said image signal being subject to one or more imaging effects including at least one or more non-isoplanatic imaging effects; performing a low-rank approximation on said set of primary deconvolution kernels or impulse responses to determine respectively a set of deconvolution modes or a set of impulse response modes, each deconvolution mode comprising a modal secondary deconvolution kernel and a modal weight function and each impulse response mode comprising a modal impulse response and a modal inverse weight function; obtaining at least approximated imaging effect-free object information related to said object by applying said modal secondary deconvolution kernels and modal weight functions or said modal impulse responses and modal inverse weight functions to said image signal.

A method and system for optimizing a metrology algorithm used by an inspection tool for inspecting predetermined sites of a semiconductor wafer during fabrication so as to allow repetitive and consistent inspection for multiple sites of the wafer by both a single inspection tool of a given type using the metrology algorithm and also across a fleet of different inspection tools of the same type using the metrology algorithm. An aggregate loss function is computed from a sum of component loss functions. In one aspect, each component loss function is amplified by a non-linear function that applies a positive gain for in-range measurements and for out-of-range measurements, applies a steep penalty that swamps any cumulative gains associated with other component loss functions. In another aspect, distribution-based metrics are used to measure similarity between two distributions of measurements for multiple locations across two different tools.

A calibration method of a detection system including an illumination system configured to illuminate a detection target, and an imaging system configured to form an image of light from the detection target on a photoelectric conversion element, the method including obtaining, for each of at least two combinations of first apertures in the illumination system and second apertures in the imaging system, each of which is formed by selecting one first aperture and one second aperture from the plurality of first apertures and the plurality of second apertures, a defocus characteristic indicating a shift amount of the image on the photoelectric conversion element with respect to a defocus amount of the detection target in a state in which each of the first aperture and the second aperture is positioned in a first position shifted from a reference position.