Abstract: An overlay marker for use with a scatterometer includes two overlying two-dimensional gratings. The two gratings have the same pitch but the upper grating has a lower duty ratio. Cross-talk between X and Y overlay measurements can therefore be avoided. The gratings may be directly overlying or off set so as to be interleaved in one or two directions.

Abstract: A lithographic apparatus arranged to transfer a pattern from a patterning device onto a substrate includes a reference set of gratings provided in the substrate, the reference set including two reference gratings having line elements in a first direction and one reference grating having line elements in a second, perpendicular, direction. A measurement set of gratings is provided on top of the reference set of gratings, the measurement set comprising three measurement gratings similar to the reference gratings. Two of the measurement gratings are oppositely biased in the second direction relative to the respective reference gratings. An overlay measurement device is provided to measure asymmetry of the three gratings in the reference set and the measurement set, and to derive from the measured asymmetry the overlay in both the first and second direction.

Abstract: Both the 1st and 0th diffraction orders are detected in a scatterometer. The 1st diffraction orders are used to detect the overlay error. The 0th diffraction order is then used to flag if this is a false overlay error calculation of magnitude greater than the bias but smaller than the pitch of the grating.

Abstract: An inspection system is arranged to measure an overlay error by projecting a plurality of radiation beams, differing in wavelength and/or polarization, onto two targets. A first radiation beam is projected onto a first target and the reflected radiation A1+ is detected. The first target comprises two gratings having a bias +d with respect to each other. The first radiation beam is also projected on to a second target, which comprises two gratings having a bias ?d with respect to each other, and the reflected radiation A1? is detected. A second radiation beam, having a different wavelength and/or polarization from the first radiation beam, is projected onto the first target and reflected radiation A2+ is detected and projected onto the second target and reflected radiation A2? is detected. Detected radiations A1+, A1?, A2+, and A2? is used to determine the overlay error.

Abstract: In a method to produce an alignment mark, an oxide layer and sacrificial layer are processed to comprise recesses. The recesses are filled with a filler material. During filling the recesses, a layer of filler material is formed on the sacrificial layer. The layer of filler material is removed by chemical mechanical polishing. The sacrificial layer protects the oxide layer during filling the recesses and removing the layer of filler material. The sacrificial layer is then removed by etching. This provides an unscratched oxide layer with protrusions. The oxide layer with protrusions is covered with a conducting layer whereby the protrusions punch through the oxide layer to form related protrusions. The related protrusions form an alignment mark.

Abstract: In a double exposure process to print features at a reduced pitch, the critical dimension of features printed in the first exposure is measured and used as a target for the second exposure.

Abstract: A lithographic apparatus arranged to transfer a pattern from a patterning device onto a substrate includes a reference set of gratings provided in the substrate, the reference set including two reference gratings having line elements in a first direction and one reference grating having line elements in a second, perpendicular, direction. A measurement set of gratings is provided on top of the reference set of gratings, the measurement set comprising three measurement gratings similar to the reference gratings. Two of the measurement gratings are oppositely biased in the second direction relative to the respective reference gratings. An overlay measurement device is provided to measure asymmetry of the three gratings in the reference set and the measurement set, and to derive from the measured asymmetry the overlay in both the first and second direction.

Abstract: An alignment sensor includes a spatially coherent radiation source that supplies a radiation beam to an angle-resolved scatterometer. Alignment is performed by detecting beats in the scatter spectrum during scanning of the substrate relative to the scatterometer.

Abstract: A method of producing a marker on a substrate includes projecting a patterned beam on a layer of resist disposed on a substrate in a lithographic apparatus to create a latent marker; and locally heating the substrate at the marker location in the lithographic apparatus to transform the latent marker into a detectable marker.

Abstract: In a device manufacturing method and lithographic apparatus wherein a pattern is transferred from a patterning device onto a substrate, a measurement target is provided on the substrate in a process enabling execution of a substrate measurement using radiation of a first wavelength. Subsequently the measurement target is transformed in a grid of conducting material, the grid having grid openings which are smaller than the first wavelength. The space in the scribe lane where the measurement target was, is now shielded and may be used again in further layers or processing steps of the substrate.

Abstract: In a device manufacturing method and a metrology apparatus, metrology measurements are executed using radiation having a first wavelength. Subsequently a grid of conducting material is applied on the substrate, the grid having grid openings which in a first direction in the plane of the grid are smaller than the first wavelength. The space in the scribe lane where the measurement target was, is now shielded and may be used again in further layers or processing steps of the substrate.

Abstract: A method of producing a marker on a substrate includes projecting a patterned beam on a layer of resist disposed on a substrate in a lithographic apparatus to create a latent marker; and locally heating the substrate at the marker location in the lithographic apparatus to transform the latent marker into a detectable marker.

Abstract: A method of selecting a grid model for correcting a process recipe for grid deformations in a lithographic apparatus is disclosed. First a set of grid models is provided. Subsequently, alignment data are obtained by performing an alignment measurement on a plurality of alignment marks on a number of substrates. For each grid model it is checked whether the alignment data is suitable to solve the grid model. If so, the grid model is added to a subset of grid models. The grid model with lowest residuals is selected. In addition to alignment data, metrology data may be obtained by performing an overlay measurement on a plurality of overlay marks on the number of substrates. For each grid model of the subset simulated metrology data may then be determined that is used to determine overlay performance indicators. The grid model is then selected using the overlay performance indicators.

Abstract: An overlay marker for use with a scatterometer includes two overlying two-dimensional gratings. The two gratings have the same pitch but the upper grating has a lower duty ratio. Cross-talk between X and Y overlay measurements can therefore be avoided. The gratings may be directly overlying or off set so as to be interleaved in one or two directions.

Abstract: Each target used in a method of measuring overlay using a scatterometer includes a first portion and a second portion, the first portion has features varying only in a first direction and the second portion has features only varying in a second direction. The first and second directions are orthogonal, thus eliminating cross talk between the directions, and improving the accuracy of overlay error calculations.

Abstract: Correcting for misalignment of a substrate before it is exposed is performed using offset corrections and process corrections that are calculated based on alignment offset measurements of alignment marks and overlay measurements of overlay targets on substrates in previous batches.

Abstract: Radiation is projected onto a plurality of targets on a substrate. By assuming that the overlay error derivable from asymmetry varies smoothly across the substrate, the number of targets measured can be reduced. This may result in a smaller area of the scribe lane being used by targets for each layer of the substrate.

Abstract: A lithographic apparatus includes an illumination system configured to condition a radiation beam, a support for a patterning device, a substrate table for a substrate, a projection system, and a control system. The patterning device is capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam. The projection system is configured to project the patterned radiation beam as an image onto a target portion of the substrate along a scan path. The scan path is defined by a trajectory in a scanning direction of an exposure field of the lithographic apparatus. The control system is coupled to the support, the substrate table and the projection system for controlling an action of the support, the substrate table and the projection system, respectively. The control system is configured to correct a local distortion of the image in a region along the scan path by a temporal adjustment of the image in that region.

Abstract: A lithographic apparatus arranged to transfer a pattern from a patterning device onto a substrate includes two reference gratings provided in the substrate and two measurement gratings on top of the reference gratings, the measurement gratings being similar to the reference gratings, and oppositely biased in a single direction relative to the respective reference gratings. An overlay measurement device with an image sensor is used for obtaining pixel data of a measurement spot in each of the two measurement gratings. Asymmetry for each pixel in the measurement spot is measured, and from the pixel asymmetry measurements in associated pixels of each of the two measurement gratings an overlay value and a process dependent value is determined, as well as a quality indicator for the overlay value and the process dependent value.

Abstract: An inspection system is arranged to measure an overlay error by projecting a plurality of radiation beams, differing in wavelength and/or polarization, onto two targets. A first radiation beam is projected onto a first target and the reflected radiation A1+ is detected. The first target comprises two gratings having a bias +d with respect to each other. The first radiation beam is also projected on to a second target, which comprises two gratings having a bias ?d with respect to each other, and the reflected radiation A1? is detected. A second radiation beam, having a different wavelength and/or polarization from the first radiation beam, is projected onto the first target and reflected radiation A2+ is detected and projected onto the second target and reflected radiation A2? is detected. Detected radiations A1+, A1?, A2+, and A2? is used to determine the overlay error.