Abstract: A recipe selection method includes obtaining measurements from metrology targets, metrology targets positioned on a semiconductor substrate, obtaining measurements from in-device targets, in-device targets positioned on the semiconductor substrate, and determining a recipe for accurate metrology using both metrology target measurements and in-device metrology measurements.

Abstract: Methods for processing data from a metrology process and for obtaining calibration data are disclosed. In one arrangement, measurement data is obtained from a metrology process. The metrology process includes illuminating a target on a substrate with measurement radiation and detecting radiation redirected by the target. The measurement data includes at least a component of a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method further includes analyzing the at least a component of the detected pupil representation to determine either or both of a position property and a focus property of a radiation spot of the measurement radiation relative to the target.

Abstract: A recipe selection method includes obtaining measurements from metrology targets, metrology targets positioned on a semiconductor substrate, obtaining measurements from in-device targets, in-device targets positioned on the semiconductor substrate, and determining a recipe for accurate metrology using both metrology target measurements and in-device metrology measurements.

Abstract: Methods of determining a value of a parameter of interest are disclosed. In one arrangement, a symmetric component and an asymmetric component of a detected pupil representation from illuminating a target are derived. A first metric characterizing the symmetric component and a second metric characterizing the asymmetric component vary non-monotonically as a function of the parameter of interest over a reference range of values of the parameter of interest. A combination of the derived symmetric component and the derived asymmetric component are used to identify a correct value from a plurality of candidate values of the parameter of interest.

Abstract: Methods of optimizing a metrology process are disclosed. In one arrangement, measurement data from a plurality of applications of the metrology process to a first target on a substrate are obtained. Each application of the metrology process includes illuminating the first target with a radiation spot and detecting radiation redirected by the first target. The applications of the metrology process include applications at a) plural positions of the radiation spot relative to the first target, and/or b) plural focus heights of the radiation spot. The measurement data includes, for each application of the metrology process, a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method includes determining an optimal alignment and/or an optimal focus height based on comparisons between the detected pupil representations in the measurement data and a reference pupil representation.

Abstract: Methods of determining an optimal focus height are disclosed. In one arrangement, measurement data from a plurality of applications of the metrology process to a target are obtained. Each application of the metrology process includes illuminating the target with a radiation spot and detecting radiation redirected by the target. The applications of the metrology process include applications at different nominal focus heights. The measurement data includes, for each application of the metrology process, at least a component of a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method includes determining an optimal focus height for the metrology process using the obtained measurement data.

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: Methods of determining a value of a parameter of interest are disclosed. In one arrangement, a symmetric component and an asymmetric component of a detected pupil representation from illuminating a target are derived. A first metric characterizing the symmetric component and a second metric characterizing the asymmetric component vary non-monotonically as a function of the parameter of interest over a reference range of values of the parameter of interest. A combination of the derived symmetric component and the derived asymmetric component are used to identify a correct value from a plurality of candidate values of the parameter of interest.

Abstract: Methods of optimizing a metrology process are disclosed. In one arrangement, measurement data from a plurality of applications of the metrology process to a first target on a substrate are obtained. Each application of the metrology process includes illuminating the first target with a radiation spot and detecting radiation redirected by the first target. The applications of the metrology process include applications at a) plural positions of the radiation spot relative to the first target, and/or b) plural focus heights of the radiation spot. The measurement data includes, for each application of the metrology process, a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method includes determining an optimal alignment and/or an optimal focus height based on comparisons between the detected pupil representations in the measurement data and a reference pupil representation.

Abstract: Methods of determining an optimal focus height are disclosed. In one arrangement, measurement data from a plurality of applications of the metrology process to a target are obtained. Each application of the metrology process includes illuminating the target with a radiation spot and detecting radiation redirected by the target. The applications of the metrology process include applications at different nominal focus heights. The measurement data includes, for each application of the metrology process, at least a component of a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method includes determining an optimal focus height for the metrology process using the obtained measurement data.

Abstract: Methods for processing data from a metrology process and for obtaining calibration data are disclosed. In one arrangement, measurement data is obtained from a metrology process. The metrology process includes illuminating a target on a substrate with measurement radiation and detecting radiation redirected by the target. The measurement data includes at least a component of a detected pupil representation of an optical characteristic of the redirected radiation in a pupil plane. The method further includes analyzing the at least a component of the detected pupil representation to determine either or both of a position property and a focus property of a radiation spot of the measurement radiation relative to the target.

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.