The present invention provides an exposure apparatus that performs an exposure process to transfer a pattern of a mask to a substrate, including a projection optical system configured to project the pattern of the mask onto the substrate, a measurement pattern arranged on an object plane of the projection optical system and including a plurality of pattern elements having different positions in an optical axis direction of the projection optical system, a first detection unit configured to detect light from the measurement pattern via the projection optical system, and a control unit configured to control a relative position between the mask and the substrate in the optical axis direction when the exposure process is performed.

A mirror array, at least some of the mirrors of the array comprising a reflective surface and an arm which extends from a surface opposite to the reflective surface, wherein the mirror array further comprises a support structure provided with a plurality of sensing apparatuses, the sensing apparatuses being configured to measure gaps between the sensing apparatuses and the arms which extend from the mirrors.

A control system controls a drive system of a substrate holder, based on correction information to compensate for measurement error of a measurement system including an encoder system that occurs due to movement of at least one of a plurality of grating areas (scale), a plurality of heads and a substrate holder, and position information measured by the measurement system, and a measurement beam from a head of each of the plurality of heads moves off from one of the plurality of grating areas and switches to another adjacent grating area, during the movement of the substrate holder in the X-axis direction.

An apparatus (100) for receiving input radiation (108) and broadening a frequency range of the input radiation so as to provide broadband output radiation (110). The apparatus comprises a fiber (102), wherein the fiber (102) may comprise a hollow core (104) for guiding radiation propagating through the fiber (102). The apparatus (100) further comprises an apparatus for providing a gas mixture (106) within the hollow core (104). The gas mixture (106) comprises a hydrogen component, and a working component, wherein the working component is for broadening a frequency range of a received input radiation (108) so as to provide the broadband output radiation (110). The apparatus may be included in a radiation source.

Methods and apparatus for measuring a parameter of interest of a target structure formed on substrate are disclosed. In one arrangement, the target structure comprises a first sub-target and a second sub-target. The first sub-target comprises a first bias and the second sub-target comprises a second bias. The method comprises determining the parameter of interest using a detected or estimated reference property of radiation at a first wavelength scattered from the first sub-target and a detected or estimated reference property of radiation at a second wavelength scattered from the second sub-target. The first wavelength is different to the second wavelength.

Disclosed is a lithography process on a sample with at least one emitter, the process including: putting at least one layer of resist above the sample; exciting one selected emitter with light through the at least one layer of resist; detecting light emitted by the excited selected emitter and determining a position of the selected emitter; and curing with a light beam a part of the at least one layer of resist above the position of the selected emitter, the light beam being a shaped light beam having a cross-section, this cross-section having a central part, an intermediate part surrounding the central part and a border part surrounding the intermediate part, the intensity of the shaped light beam on the at least one layer of resist reaching a maximum at the intermediate part.

A scatterometer performs diffraction based measurements of one or more parameters of a target structure. To make two-color measurements in parallel, the structure is illuminated simultaneously with first radiation (302) having a first wavelength and a first angular distribution and with second radiation (304) having a second wavelength and a second angular distribution. The collection path (CP) includes a segmented wavelength-selective filter (21, 310) arranged to transmit wanted higher order portions of the diffracted first radiation (302X, 302Y) and of the diffracted second radiation (304X, 304Y), while simultaneously blocking zero order portions (302, 304) of both the first radiation and second radiation. The illumination path (IP) in one embodiment includes a matching segmented wavelength-selective filter (13, 300), oriented such that a zero order ray passing through the illumination optical system and the collection optical system will be blocked by one of said filters or the other, depending on its wavelength.

A control system controls a drive system of a substrate holder, based on correction information to compensate for measurement error of a measurement system including an encoder system that occurs due to movement of at least one of a plurality of grating areas (scale), a plurality of heads and a substrate holder, and position information measured by the measurement system, and a measurement beam from a head of each of the plurality of heads moves off from one of the plurality of grating areas and switches to another adjacent grating area, during the movement of the substrate holder in the X-axis direction.

A metrology apparatus (302) includes a higher harmonic generation (HHG) radiation source for generating (310) EUV radiation. Operation of the HHG source is monitored using a wavefront sensor (420) which comprises an aperture array (424, 702) and an image sensor (426). A grating (706) disperses the radiation passing through each aperture so that the image detector captures positions and intensities of higher diffraction orders for different spectral components and different locations across the beam. In this way, the wavefront sensor can be arranged to measure a wavefront tilt for multiple harmonics at each location in said array. In one embodiment, the apertures are divided into two subsets (A) and (B), the gratings (706) of each subset having a different direction of dispersion. The spectrally resolved wavefront information (430) is used in feedback control (432) to stabilize operation of the HGG source, and/or to improve accuracy of metrology results.

In a method for characterizing at least one optical component of a projection exposure apparatus (1), an intensity distribution of the illumination radiation (2) is detected in a field plane of the projection exposure apparatus (1) with a measuring device (31) and predicted values of an optical parameter are spatially determined therefrom over at least one predefined surface.