Abstract: A method of determining overlay of a patterning process, the method including: obtaining a detected representation of radiation redirected by one or more physical instances of a unit cell, wherein the unit cell has geometric symmetry at a nominal value of overlay and wherein the detected representation of the radiation was obtained by illuminating a substrate with a radiation beam such that a beam spot on the substrate was filled with the one or more physical instances of the unit cell; and determining, from optical characteristic values from the detected radiation representation, a value of a first overlay for the unit cell separately from a second overlay for the unit cell that is also obtainable from the same optical characteristic values, wherein the first overlay is in a different direction than the second overlay or between a different combination of parts of the unit cell than the second overlay.

Abstract: A method of determining a parameter of a patterning process, the method including: obtaining a detected representation of radiation redirected by a structure having geometric symmetry at a nominal physical configuration, wherein the detected representation of the radiation was obtained by illuminating a substrate with a radiation beam such that a beam spot on the substrate was filled with the structure; and determining, by a hardware computer system, a value of the patterning process parameter based on optical characteristic values from an asymmetric optical characteristic distribution portion of the detected radiation representation with higher weight than another portion of the detected radiation representation, the asymmetric optical characteristic distribution arising from a different physical configuration of the structure than the nominal physical configuration.

Abstract: A target formed on a substrate, the target having: an alignment structure; and a metrology structure; wherein the alignment structure comprises structures that are arranged to generate a beat pattern when the alignment structure is illuminated with source radiation. Advantageously, when the target is illuminated, the beat pattern that appears in an image of the target allows the target to be easily identified using a pattern recognition technique.

Abstract: A substrate has first and second target structures formed by a lithographic process. Each target structure has a two-dimensional periodic structure formed in a single layer using first and second lithographic steps. The first target structure has features defined in the second lithographic step displaced relative to features defined in the first lithographic step by a first bias amount. The second target structure has features defined in the second lithographic step displaced relative to features defined in the first lithographic step by a second bias amount. An angle-resolved scatter spectrum of the first target structure and an angle-resolved scatter spectrum of the second target structure is obtained. A measurement of a parameter of a lithographic process is derived from the measurements using asymmetry found in the scatter spectra of the first and second target structures.

Abstract: A lithographic apparatus (LA) prints product features and at least one focus metrology pattern (T) on a substrate. The focus metrology pattern is defined by a reflective reticle and printing is performed using EUV radiation (404) incident at an oblique angle (?). The focus metrology pattern comprises a periodic array of groups of first features (422). A spacing (S1) between adjacent groups of first features is much greater than a dimension (CD) of the first features within each group. Due to the oblique illumination, the printed first features become distorted and/or displaced as a function of focus error. Second features 424 may be provided as a reference against which displacement of the first features may be seen. Measurement of this distortion and/or displacement may be by measuring asymmetry as a property of the printed pattern. Measurement can be done at longer wavelengths, for example in the range 350-800 nm.

Abstract: A method of determining a parameter of a patterning process, the method including: obtaining a detected representation of radiation redirected by a structure having geometric symmetry at a nominal physical configuration, wherein the detected representation of the radiation was obtained by illuminating a substrate with a radiation beam such that a beam spot on the substrate was filled with the structure; and determining, by a hardware computer system, a value of the patterning process parameter based on optical characteristic values from an asymmetric optical characteristic distribution portion of the detected radiation representation with higher weight than another portion of the detected radiation representation, the asymmetric optical characteristic distribution arising from a different physical configuration of the structure than the nominal physical configuration.

Abstract: A method and apparatus for obtaining focus information relating to a lithographic process. The method includes illuminating a target, the target having alternating first and second structures, wherein the form of the second structures is focus dependent, while the form of the first structures does not have the same focus dependence as that of the second structures, and detecting radiation redirected by the target to obtain for that target an asymmetry measurement representing an overall asymmetry of the target, wherein the asymmetry measurement is indicative of focus of the beam forming the target. An associated mask for forming such a target, and a substrate having such a target.

Abstract: Disclosed is method of optimizing bandwidth of measurement illumination for a measurement application, and an associated metrology apparatus. The method comprises performing a reference measurement with reference measurement illumination having a reference bandwidth and performing one or more optimization measurements, each of said one or more optimization measurements being performed with measurement illumination having a varied candidate bandwidth. The one or more optimization measurements are compared with the reference measurement; and an optimal bandwidth for the measurement application is selected based on the comparison.

Abstract: An inspection apparatus, method, and system are described herein. An example inspection apparatus includes an optical system and an imaging system. The optical system may be configured to output an illumination beam incident on a target including one or more features, the illumination beam polarized with a first polarization when incident on the target. The imaging system may be configured to obtain intensity data representing at least a portion of the illumination beam scattered by the one or more features, where the portion of the illumination beam has a second polarization orthogonal to the first polarization. The inspection apparatus may be further configured to generate image data representing an image of each of the feature(s) based on the intensity data, and determine a measurement of a parameter of interest associated with the feature(s) based on an amount of the portion of the illumination beam having the second polarization.

Abstract: A method involving determining a contribution that one or more process apparatuses make to a characteristic of a substrate after the substrate has been processed according to a patterning process by the one or more process apparatuses by removing from values of the characteristic of the substrate a contribution of a lithography apparatus to the characteristic and a contribution of one or more pre-lithography process apparatuses to the characteristic.

Abstract: Methods of determining information about a patterning process. In a method, measurement data from a metrology process applied to each of a plurality of metrology targets on a substrate is obtained. The measurement data for each metrology target includes at least a first contribution and a second contribution. The first contribution is from a parameter of interest of a patterning process used to form the metrology target. The second contribution is from an error in the metrology process. The method further includes using the obtained measurement data from all of the plurality of metrology targets to obtain information about an error in the metrology process, and using the obtained information about the error in the metrology process to extract a value of the parameter of interest for each metrology target.

Abstract: A method including: obtaining a detected representation of radiation redirected by each of a plurality of structures from a substrate additionally having a device pattern thereon, wherein each structure has an intentional different physical configuration of the respective structure than the respective nominal physical configuration of the respective structure, wherein each structure has geometric symmetry at the respective nominal physical configuration, wherein the intentional different physical configuration of the structure causes an asymmetric optical characteristic distribution and wherein a patterning process parameter measures change in the physical configuration; and determining a value, based on the detected representations and based on the intentional different physical configurations, to setup, monitor or correct a measurement recipe for determining the patterning process parameter.

Abstract: A method including: computing a value of a first variable of a pattern of, or for, a substrate processed by a patterning process by combining a fingerprint of the first variable on the substrate and a certain value of the first variable; and determining a value of a second variable of the pattern based at least in part on the computed value of the first variable.

Abstract: A target formed on a substrate, the target having: an alignment structure; and a metrology structure; wherein the alignment structure comprises structures that are arranged to generate a beat pattern when the alignment structure is illuminated with source radiation. Advantageously, when the target is illuminated, the beat pattern that appears in an image of the target allows the target to be easily identified using a pattern recognition technique.

Abstract: A method of determining a process window for a lithographic process, the process window describing a degree of acceptable variation in at least one processing parameter during the lithographic process. The method includes obtaining a set of output parameter values derived from measurements performed at a plurality of locations on a substrate, following pattern transfer to the substrate using a lithographic process, and obtaining a corresponding set of actual processing parameter values that includes an actual value of a processing parameter of the lithographic process during the pattern transfer at each of the plurality of locations. The process window is determined from the output parameter values and the actual processing parameter values. This process window may be used to improve the selection of the processing parameter at which a subsequent lithographic process is performed.

Abstract: A method and apparatus for obtaining focus information relating to a lithographic process. The method includes illuminating a target, the target having alternating first and second structures, wherein the form of the second structures is focus dependent, while the form of the first structures does not have the same focus dependence as that of the second structures, and detecting radiation redirected by the target to obtain for that target an asymmetry measurement representing an overall asymmetry of the target, wherein the asymmetry measurement is indicative of focus of the beam forming the target. An associated mask for forming such a target, and a substrate having such a target.

Abstract: Disclosed is a method of monitoring a focus parameter during a lithographic process. The method comprises acquiring first and second measurements of, respectively first and second targets, wherein the first and second targets have been exposed with a relative best focus offset. The method then comprises determining the focus parameter from first and second measurements. Also disclosed are corresponding measurement and lithographic apparatuses, a computer program and a method of manufacturing devices.

Abstract: Disclosed is a method of monitoring a lithographic process parameter, such as focus and/or dose, of a lithographic process. The method comprises acquiring a first and a second target measurement using respectively a first measurement configuration and a second measurement configuration, and determining the lithographic process parameter from a first metric derived from said first target measurement and said second target measurement. The first metric may be difference. Also disclosed are corresponding measurement and lithographic apparatuses, a computer program and a method of manufacturing devices.

Abstract: A method and apparatus for obtaining focus information relating to a lithographic process. The method includes illuminating a target, the target having alternating first and second structures, wherein the form of the second structures is focus dependent, while the form of the first structures does not have the same focus dependence as that of the second structures, and detecting radiation redirected by the target to obtain for that target an asymmetry measurement representing an overall asymmetry of the target, wherein the asymmetry measurement is indicative of focus of the beam forming the target. An associated mask for forming such a target, and a substrate having such a target.

Abstract: A method of determining exposure dose of a lithographic apparatus used in a lithographic process on a substrate. Using the lithographic process to produce a first structure on the substrate, the first structure having a dose-sensitive feature which has a form that depends on exposure dose of the lithographic apparatus on the substrate. Using the lithographic process to produce a second structure on the substrate, the second structure having a dose-sensitive feature which has a form that depends on the exposure dose of the lithographic apparatus but which has a different sensitivity to the exposure dose than the first structure. Detecting scattered radiation while illuminating the first and second structures with radiation to obtain first and second scatterometer signals. Using the first and second scatterometer signals to determine an exposure dose value used to produce at least one of the first and second structures.