The present disclosure provides a method of leveling a wafer in an exposure process. The wafer includes a plurality of regions. The wafer is loaded to an exposure system. The exposure system includes a control unit and a leveling module. The control unit of the exposure system obtains layout information of the reticle. The control unit of the exposure system assigns critical regions and non-critical regions to the regions on the wafer according to the layout information of the reticle.

Provided is a lithography apparatus capable of detecting the abnormal holding of an original in a shorter period of time. The lithography apparatus is configured to form a pattern on a substrate through use of the original, and includes: a holding unit configured to hold the original on which a first mark is formed; a measuring unit configured to pick up an image of the first mark; and a control unit configured to: cause the measuring unit to obtain the image of the first mark on the original held by the holding unit with a focus position of the measuring unit being adjusted to a reference position; and determine that the original is being abnormally held by the holding unit when a change in a first contrast, which is a contrast of the image of the first mark with respect to a reference contrast, falls out of an allowable range.

The present invention provides a measurement apparatus including a first filter unit including a plurality of first filters, and each configured to allow light having a different wavelength band to pass, a second filter unit including a plurality of second filters, and each configured to reduce light intensity of light and allow the light to pass, an obtaining unit configured to obtain data representing a transmittance of each of the plurality of second filters for a wavelength band of light having passed through each of the plurality of first filters, and a selection unit configured to select, based on the data obtained by the obtaining unit, from the plurality of second filters, one second filter arranged on an optical path together with one first filter among the plurality of first filters.

A position detector includes a detection unit configured to detect light from a first diffraction grating including a first pattern disposed in a first direction, and light from a second diffraction grating including a second pattern disposed in the first direction, and a control unit configured to obtain a relative position between the first and the second diffraction gratings based on the light detected by the detection unit. The position detector has a third pattern formed in a second direction different from the first direction at edges of the first pattern of the first diffraction grating, the third pattern has a width smaller than a width of the first pattern of the first diffraction grating.

A method for determining one or more optimized values of an operational parameter of a sensor system configured for measuring a property of a substrate is disclosed the method comprising: determining a quality parameter for a plurality of substrates; determining measurement parameters for the plurality of substrates obtained 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 parameters; and determining the one or more optimized values of the operational parameter based on the comparing.

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. Additionally, an optical rotator can be configured to receive the first polarized light and rotate the polarization of the first polarized light.

An exposure apparatus comprises a projection optical system for projecting a pattern of a mask, a substrate stage for holding a substrate, and a measurement device installed on the substrate stage, including a plate on which a substrate-side mark is formed, and a sensor for detecting light transmitted through a mask-side mark, the projection optical system, and the substrate-side mark, and configured to measure an amount of the light detected by the sensor. The substrate-side mark includes a central mark arranged in a center of a sensitive region of the sensor, and a peripheral mark arranged in a periphery of the central mark. The central mark is used in measurement of the light amount, including driving the substrate stage in a direction parallel to an optical axis of the projection optical system.

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 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 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.