Abstract: A method including obtaining a measurement result from a target on a substrate, by using a substrate measurement recipe; determining, by a hardware computer system, a parameter from the measurement result, wherein the parameter characterizes dependence of the measurement result on an optical path length of the target for incident radiation used in the substrate measurement recipe and the determining the parameter includes determining dependence of the measurement result on a relative change of wavelength of the incident radiation; and if the parameter is not within a specified range, adjusting the substrate measurement recipe.

Abstract: A method of determining topographical variation across a substrate on which one or more patterns have been applied. The method includes obtaining measured topography data representing a topographical variation across a substrate on which one or more patterns have been applied by a lithographic process; and combining the measured topography data with knowledge relating to intra-die topology to obtain derived topography data having a resolution greater than the resolution of the measured topography data. Also disclosed is a corresponding level sensor apparatus and lithographic apparatus having such a level sensor apparatus, and a more general method of determining variation of a physical parameter from first measurement data of variation of the physical parameter across the substrate and intra-die measurement data of higher resolution than the first measurement data and combining these.

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: A focus metrology target includes one or more periodic arrays of features. A measurement of focus performance of a lithographic apparatus is based at least in part on diffraction signals obtained from the focus metrology target. Each periodic array of features includes a repeating arrangement of first zones interleaved with second zones, a feature density being different in the first zones and the second zones. Each first zone includes a repeating arrangement of first features. A minimum dimension of each first feature is close to but not less than a resolution limit of the printing by the lithographic apparatus, so as to comply with a design rule in a given a process environment. A region of high feature density may further include a repeating arrangement of larger features.

Abstract: A method including obtaining a measurement result from a target on a substrate, by using a substrate measurement recipe; determining, by a hardware computer system, a parameter from the measurement result, wherein the parameter characterizes dependence of the measurement result on an optical path length of the target for incident radiation used in the substrate measurement recipe and the determining the parameter includes determining dependence of the measurement result on a relative change of wavelength of the incident radiation; and if the parameter is not within a specified range, adjusting the substrate measurement recipe.

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: Focus performance of a lithographic apparatus is measured using pairs of targets that have been exposed (1110) with an aberration setting (e.g. astigmatism) that induces a relative best focus offset between them. A calibration curve (904) is obtained in advance by exposing similar targets on FEM wafers (1174, 1172). In a set-up phase, calibration curves are obtained using multiple aberration settings, and an anchor point (910) is recorded, where all the calibration curves intersect. When a new calibration curve is measured (1192), the anchor point is used to produce an adjusted updated calibration curve (1004?) to cancel focus drift and optionally to measure drift of astigmatism. Another aspect of the disclosure (FIG. 13-15) uses two aberration settings (+AST, ?AST) in each measurement, reducing sensitivity to astigmatism drift. Another aspect (FIG. 16-17) uses pairs of targets printed with relative focus offsets, by double exposure in one resist layer.

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 lithographic apparatus applies a pattern onto a substrate using an optical projection system. The apparatus includes an optical level sensor and an associated processor for obtaining a height map of the substrate surface prior to applying the pattern. A controller uses the height map to control focusing with respect to the projection system when applying the pattern. The processor is further arranged to use information relating to processing previously applied to the substrate to define at least first and second regions of the substrate and to vary the manner in which the measurement signals are used to control the focusing, between the first and second regions. For example, an algorithm to calculate height values from optical measurement signals can be varied according to differences in known structure and/or materials. Measurements from certain regions can be selectively excluded from calculation of the height map and/or from use in the focusing.

Abstract: A method for adjusting a lithography process, wherein processing parameters of the lithography process include a first group of processing parameters and a second group of processing parameters, the method including: obtaining a change of the second group of processing parameters; determining a change of a sub- process window (sub-PW) as a result of the change of the second group of processing parameters, wherein the sub-PW is spanned by only the first group of processing parameters; and adjusting the first group of processing parameters based on the change of the sub-PW.

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: Disclosed is a substrate comprising a combined target for measurement of overlay and focus. The target comprises: a first layer comprising a first periodic structure; and a second layer comprising a second periodic structure overlaying the first periodic structure. The target has structural asymmetry which comprises a structural asymmetry component resultant from unintentional mismatch between the first periodic structure and the second periodic structure, a structural asymmetry component resultant from an intentional positional offset between the first periodic structure and the second periodic structure and a focus dependent structural asymmetry component which is dependent upon a focus setting during exposure of said combined target on said substrate. Also disclosed is a method for forming such a target, and associated lithographic and metrology apparatuses.

Abstract: Disclosed is a method of determining a correction for measured values of radiation diffracted from a target comprising a plurality of periodic structures, subsequent to measurement of the target using measurement radiation defining a measurement field. The correction acts to correct for measurement field location dependence in the measured values. The method comprises performing a first and second measurements of the periodic structures; and determining a correction from said first measurement and said second measurement. The first measurement is performed with said target being in a normal measurement location with respect to the measurement field. The second measurement is performed with the periodic structure in a shifted location with respect to the measurement field, said shifted location comprising the location of another of said periodic structures when said target is in said normal measurement location with respect to the measurement field.

Abstract: A method includes determining topographic information of a substrate for use in a lithographic imaging system, determining or estimating, based on the topographic information, imaging error information for a plurality of points in an image field of the lithographic imaging system, adapting a design for a patterning device based on the imaging error information. In an embodiment, a plurality of locations for metrology targets is optimized based on imaging error information for a plurality of points in an image field of a lithographic imaging system, wherein the optimizing involves minimizing a cost function that describes the imaging error information. In an embodiment, locations are weighted based on differences in imaging requirements across the image field.

Abstract: A lithographic apparatus including a substrate table position measurement system and a projection system position measurement system to measure a position of the substrate table and the projection system, respectively. The substrate table position measurement system includes a substrate table reference element mounted on the substrate table and a first sensor head. The substrate table reference element extends in a measurement plane substantially parallel to the holding plane of a substrate on substrate table. The holding plane is arranged at one side of the measurement plane and the first sensor head is arranged at an opposite side of the measurement plane. The projection system position measurement system includes one or more projection system reference elements and a sensor assembly. The sensor head and the sensor assembly or the associated projection system measurement elements are mounted on a sensor frame.

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: Disclosed is a substrate comprising a combined target for measurement of overlay and focus. The target comprises: a first layer comprising a first periodic structure; and a second layer comprising a second periodic structure overlaying the first periodic structure. The target has structural asymmetry which comprises a structural asymmetry component resultant from unintentional mismatch between the first periodic structure and the second periodic structure, a structural asymmetry component resultant from an intentional positional offset between the first periodic structure and the second periodic structure and a focus dependent structural asymmetry component which is dependent upon a focus setting during exposure of said combined target on said substrate. Also disclosed is a method for forming such a target, and associated lithographic and metrology apparatuses.

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: Disclosed is a method of determining a correction for measured values of radiation diffracted from a target comprising a plurality of periodic structures, subsequent to measurement of the target using measurement radiation defining a measurement field. The correction acts to correct for measurement field location dependence in the measured values. The method comprises performing a first and second measurements of the periodic structures; and determining a correction from said first measurement and said second measurement. The first measurement is performed with said target being in a normal measurement location with respect to the measurement field. The second measurement is performed with the periodic structure in a shifted location with respect to the measurement field, said shifted location comprising the location of another of said periodic structures when said target is in said normal measurement location with respect to the measurement field.

Abstract: A lithographic apparatus applies a pattern onto a substrate using an optical projection system. The apparatus includes an optical level sensor and an associated processor for obtaining a height map of the substrate surface prior to applying the pattern. A controller uses the height map to control focusing with respect to the projection system when applying the pattern. The processor is further arranged to use information relating to processing previously applied to the substrate to define at least first and second regions of the substrate and to vary the manner in which the measurement signals are used to control the focusing, between the first and second regions. For example, an algorithm to calculate height values from optical measurement signals can be varied according to differences in known structure and/or materials. Measurements from certain regions can be selectively excluded from calculation of the height map and/or from use in the focusing.