A method of determining the position of an alignment mark on a substrate, the alignment mark having first and second segment, the method including illuminating the alignment mark with radiation, detecting radiation diffracted by the alignment mark and generating a resulting alignment signal. The alignment signal has a first component received during illumination of the first segment only, a second component received during illumination of the second segment only, and a third component received during simultaneous illumination of both segments. The positions of the segments are determined using the first component, the second component and the third component of the alignment signal.

A method including: determining recipe consistencies between one substrate measurement recipe of a plurality of substrate measurement recipes and each other substrate measurement recipe of the plurality of substrate measurement recipes; calculating a function of the recipe consistencies; eliminating the one substrate measurement recipe from the plurality of substrate measurement recipes if the function meets a criterion; and reiterating the determining, calculating and eliminating until a termination condition is met. Also disclosed herein is a substrate measurement apparatus, including a storage configured to store a plurality of substrate measurement recipes, and a processor configured to select one or more substrate measurement recipes from the plurality of substrate measurement recipes based on recipe consistencies among the plurality of substrate measurement recipes.

A metrology system includes a radiation source that generates light, an optical modulation unit, a reflector, an interferometer, and a detector. The optical modulating unit temporally separates a first polarization mode of the light from a second polarization mode of the light. The reflector directs the light towards a substrate. The interferometer interferes the diffracted light from a pattern on the substrate, or reflected light from the substrate, and produces output light from the interference. The detector receives the output light from the interferometer. The first and second polarization modes of the output light are temporally separated at the detector.

Aspects of the present disclosure generally relate to a digital lithography system and methods for alignment resolution with the digital lithography system. The digital lithography system includes a metrology system configured to improve overlay alignment for different layers of the lithography process. The metrology system includes an inline metrology system (IMS) in combination with an on tool metrology system (OTM), which enable substrate overlay alignment and die placement correction. The inline metrology system may be positioned on an inline metrology tool and the on tool metrology system is positioned on a digital lithography tool. The inline metrology system facilitates measurement of high-throughput measurement inline metrology data for marks such as die marks and global alignment marks for verification of process stability and die placement data for digital data correction. This inline metrology data can be compared with a design file to determine offsets for the digital data correction.

Disclosed is a method for measuring a target located on a substrate beneath at least one layer. The method comprises exciting said at least one layer with pump radiation comprising at least one pump wavelength, so as to generate an acoustic wave within said at least one layer which reflects of said target thereby generating an acoustic replica of said target at a surface of said substrate and illuminating said acoustic replica with probe radiation comprising at least one probe wavelength and capturing the resultant scattered probe radiation, scattered from the acoustic replica. One or both of said exciting step and said illuminating step comprises generating Surface Plasmon Polaritons (SPPs) on residual topography of said at least one layer resultant from said target.

An imprint apparatus which includes a plurality of stations in which an imprint material supplied to an imprint region on a substrate is formed using a mold and a pattern is formed in the imprint region. The imprint apparatus includes: a holder provided in each of the plurality of stations and configured to hold the substrate and to adjust a temperature of the substrate; and a controller configured to output a target value used to adjust the temperature to the holder in a station in which a pattern is formed in a substrate among the plurality of stations on the basis of a size of the imprint region and a temperature of the substrate.

A method for determining one or more optimized values of an operational parameter of a sensor system configured to measure a property of a substrate is disclosed. The method includes: determining a quality parameter for a plurality of substrates; determining measurement parameter values for the plurality of substrates using the sensor system for a plurality of values of the operational parameter; comparing a substrate to substrate variation of the quality parameter and a substrate to substrate variation of a mapping of the measurement parameter values; and determining the one or more optimized values of the operational parameter based on the comparing.

A method of determining positions of marks, the marks comprising periodic structures, at least some of the structures comprising periodic sub-structures, the sub-structures having a smaller period than the structures, the marks formed with positional offsets between the sub-structures and structures, the positional offsets caused by a combination of both known and unknown components, the method comprising illuminating a plurality of the marks with radiation having different characteristics, detecting radiation diffracted by the marks using one or more detectors which produce output signals, discriminating between constituent parts of the signals, the discriminating based on a variation of the signals as a function of spatial positions of the marks on a substrate, selecting at least one of the constituent parts of the signals, and using the at least one selected constituent part, and information relating to differences between the known components, to calculate a corrected position of at least one mark.

Methods and apparatus for detecting metrology data are provided herein. For example, an apparatus comprises a substrate support configured to support a substrate and another substrate disposed on the substrate, an incoherent light source configured to transmit an illumination beam through the substrate and the another substrate, a set of optics configured to direct the illumination beam when transmitted through the substrate and the another substrate, an actuator operably coupled to the substrate support and configured to move the substrate and another substrate back and forth in a scanning pattern, and a sensor operably coupled to the actuator, synchronized therewith, and configured to receive the illumination beam from the set of optics to obtain subsurface images of the substrate and the another substrate.

A dark field metrology device includes an objective lens arrangement and a zeroth order block to block zeroth order radiation. The objective lens arrangement directs illumination onto a specimen to be measured and collects scattered radiation from the specimen, the scattered radiation including zeroth order radiation and higher order diffracted radiation. The dark field metrology device is operable to perform an illumination scan to scan illumination over at least two different subsets of the maximum range of illumination angles; and simultaneously perform a detection scan which scans the zeroth order block and/or the scattered radiation with respect to each other over a corresponding subset of the maximum range of detection angles during at least part of the illumination scan.