Abstract: In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

Abstract: In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

Abstract: A method for determining a target feature in a model of a patterning process based on local electric fields estimated for the patterning process. The method includes obtaining a mask stack region of interest. The mask stack region of interest has one or more characteristics associated with propagation of electromagnetic waves through the mask stack region of interest. The mask stack region of interest includes the target feature. The method includes estimating a local electric field based on the one or more characteristics associated with the propagation of electromagnetic waves through the mask stack region of interest. The local electric field is estimated for a portion of the mask stack region of interest in proximity to the target feature. The method includes determining the target feature based on the estimated local electric field.

Abstract: A method for determining a target feature in a model of a patterning process based on local electric fields estimated for the patterning process is described. The method includes obtaining a mask stack region of interest. The mask stack region of interest has one or more characteristics associated with propagation of electromagnetic waves through the mask stack region of interest. The mask stack region of interest includes the target feature. The method includes estimating a local electric field based on the one or more characteristics associated with the propagation of electromagnetic waves through the mask stack region of interest. The local electric field is estimated for a portion of the mask stack region of interest in proximity to the target feature. The method includes determining the target feature based on the estimated local electric field.

Abstract: A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.

Abstract: A method includes exposing number of fields on a substrate, obtaining data about a field and correcting exposure of the field in subsequent exposures. The method includes defining one or more sub-fields of the field based on the obtained data. Data relating to each sub-field is processed to produce sub-field correction information. A subsequent exposure of the one or more sub-fields is corrected using the sub-field correction information. By controlling a lithographic apparatus by reference to data of a particular sub-field within a field, overlay error can be reduced or minimized for a critical feature, rather than being averaged over the whole field. By controlling a lithographic apparatus with reference to a sub-field rather than only the whole field, a residual error can be reduced in each sub-field.

Abstract: In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

Abstract: A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.

Abstract: In a lithographic process, product units such as semiconductor wafers are subjected to lithographic patterning operations and chemical and physical processing operations. Alignment data or other measurements are made at stages during the performance of the process to obtain object data representing positional deviation or other parameters measured at points spatially distributed across each unit. This object data is used to obtain diagnostic information by performing a multivariate analysis to decompose a set of vectors representing the units in the multidimensional space into one or more component vectors. Diagnostic information about the industrial process is extracted using the component vectors. The performance of the industrial process for subsequent product units can be controlled based on the extracted diagnostic information.

Abstract: A method of determining an optimal operational parameter setting of a metrology system is described. Free-form substrate shape measurements are performed. A model is applied, transforming the measured warp to modeled warp scaling values. Substrates are clamped to a chuck, causing substrate deformation. Alignment marks of the substrates are measured using an alignment system with four alignment measurement colors. Scaling values thus obtained are corrected with the modeled warp scaling values to determine corrected scaling values. An optimal alignment measurement color is determined, based on the corrected scaling values. Optionally, scaling values are selected that were measured using the optimal alignment measurement color and a substrate grid is determined using the selected scaling values. A substrate may be exposed using the determined substrate grid to correct exposure of the substrate.

Abstract: Methods and apparatuses for determining in-plane distortion (IPD) across a substrate having a plurality of patterned regions. A method includes obtaining intra-region data indicative of a local stress distribution across one of the plurality of patterned regions; determining, based on the intra-region data, inter-region data indicative of a global stress distribution across the substrate; and determining, based on the inter-region data, the IPD across the substrate.

Abstract: A method to change an etch parameter of a substrate etching process, the method including: making a first measurement of a first metric associated with a structure on a substrate before being etched; making a second measurement of a second metric associated with a structure on a substrate after being etched; and changing the etch parameter based on a difference between the first measurement and the second measurement.

Abstract: A method and control system for determining stress in a substrate. The method includes determining a measured position difference between a measured position of at least one first feature and a measured position of at least one second feature which have been applied on a substrate, and determining local stress in the substrate from the measured position difference.

Abstract: Methods and apparatuses for determining a position of an alignment mark applied to a region of a first layer on a substrate using a lithographic process by: obtaining an expected position of the alignment mark; obtaining a geometrical deformation of the region due to a control action correcting the lithographic process; obtaining a translation of the alignment mark due to the geometrical deformation; and determining the position of the alignment mark based on the expected position and the translation.

Abstract: A method for predicting a property associated with a product unit. The method may include: obtaining a plurality of data sets, wherein each of the plurality of data sets includes data associated with a spatial distribution of a parameter across the product unit; representing each of the plurality of data sets as a multidimensional object; obtaining a convolutional neural network model trained with previously obtained multidimensional objects and properties of previous product units; and applying the convolutional neural network model to the plurality of multidimensional objects representing the plurality of data sets, to predict the property associated with the product unit.

Abstract: A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.

Abstract: A method for determining a target feature in a model of a patterning process based on local electric fields estimated for the patterning process is described. The method includes obtaining a mask stack region of interest. The mask stack region of interest has one or more characteristics associated with propagation of electromagnetic waves through the mask stack region of interest. The mask stack region of interest includes the target feature. The method includes estimating a local electric field based on the one or more characteristics associated with the propagation of electromagnetic waves through the mask stack region of interest. The local electric field is estimated for a portion of the mask stack region of interest in proximity to the target feature. The method includes determining the target feature based on the estimated local electric field.

Abstract: Methods and associated apparatus for reconstructing a free-form geometry of a substrate, the method including: positioning the substrate on a substrate holder configured to retain the substrate under a retaining force that deforms the substrate from its free-form geometry; measuring a height map of the deformed substrate; and reconstructing the free-form geometry of the deformed substrate based on an expected deformation of the substrate by the retaining force and the measured height map.

Abstract: A method includes exposing number of fields on a substrate, obtaining data about a field and correcting exposure of the field in subsequent exposures. The method includes defining one or more sub-fields of the field based on the obtained data. Data relating to each sub-field is processed to produce sub-field correction information. A subsequent exposure of the one or more sub-fields is corrected using the sub-field correction information. By controlling a lithographic apparatus by reference to data of a particular sub-field within a field, overlay error can be reduced or minimized for a critical feature, rather than being averaged over the whole field. By controlling a lithographic apparatus with reference to a sub-field rather than only the whole field, a residual error can be reduced in each sub-field.

Abstract: A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.