A lithography system comprises an illumination system configured to produce abeam of radiation, a support configured to support a patterning device configured to impart a pattern on the beam, a projection system configured to project the patterned beam onto a substrate, and an alignment system comprising an illuminator. The illuminator comprises an optical fiber, an optical fiber protector (714), an optical fiber support (700) comprising a first support arm assembly configured to support the optical fiber protector, an optical system, and an optical system support comprising a second support arm assembly configured to support the optical system.

An apparatus for measuring a position of a mark on a substrate, the apparatus comprising: an illumination system configured to condition at least one radiation beam to form a plurality of illumination spots spatially distributed in series such that during scanning of the substrate the plurality of illumination spots are incident on the mark sequentially, and a projection system configured to project radiation diffracted by the mark from the substrate, the diffracted radiation being produced by diffraction of the plurality of illumination spots by the mark; wherein the projection system is further configured to modulate the diffracted radiation and project the modulated radiation onto a detecting system configured to produce signals corresponding to each of the plurality of illumination spots, the signals being combined to determine the position of the mark.

A lithographic apparatus includes an illumination system to produce a beam of radiation, a support to support a patterning device to impart a pattern on the beam, a projection system to project the patterned beam onto a substrate, and a metrology system that includes a radiation source to generate radiation, an optical element to direct the radiation toward a target, a detector to receive a first and second radiation scattered by the target and produce a first and second measurement respectively based on the received first and second radiation, and a controller. The controller determines a correction for the first measurement, an error between the correction for the first measurement and the first measurement, and a correction for the second measurement based on the correction for the first measurement, the second measurement, and the error. The lithographic apparatus uses the correction to adjust a position of a substrate.

Disclosed is a bandwidth calculation system for determining a desired wavelength bandwidth for a measurement beam in a mark detection system, the bandwidth calculation system comprising a processing unit configured to determine the desired wavelength bandwidth based on mark geometry information, e.g. comprising mark depth information representing a depth of a mark. In an embodiment the desired wavelength bandwidth is based on a period and/or a variance parameter of a mark detection error function. The invention further relates to a mark detection system, a position measurement system and a lithographic apparatus comprising the bandwidth calculation system, as well as a method for determining a desired wavelength bandwidth.

A method to reduce sensitivity of a level sensor, arranged to measure a height of a substrate, to variations of a property of an optical component in the level sensor includes directing a beam of radiation toward a diffractive element and directing the beam, via an optical system, to a first reflective element at a first angle of incidence. The beam has a first polarization and a second polarization that is perpendicular to the first polarization. The first reflective element reflects the beam toward a second reflective element at a second angle of incidence causing the beam to impinge on the substrate. The first and second angles of incidence are selected to reduce variations of a ratio of intensities of the first polarization to the second polarization of the beam imparted by a property of a layer of at least one of the first and second reflective elements.

An illumination source apparatus (500), suitable for use in a metrology apparatus for the characterization of a structure on a substrate, the illumination source apparatus comprising: a high harmonic generation, HHG, medium (502); a pump radiation source (506) operable to emit a beam of pump radiation (508); and adjustable transformation optics (510) configured to adjustably transform the transverse spatial profile of the beam of pump radiation to produce a transformed beam (518) such that relative to the centre axis of the transformed beam, a central region of the transformed beam has substantially zero intensity and an outer region which is radially outwards from the centre axis of the transformed beam has a non-zero intensity, wherein the transformed beam is arranged to excite the HHG medium so as to generate high harmonic radiation (540), wherein the location of said outer region is dependent on an adjustment setting of the adjustable transformation optics.

A system for and method of processing a wafer in which a scan signal is analyzed locally to extract information about alignment, overlay, mark quality, wafer quality, and the like.

A lithographic apparatus includes an illumination system to produce a beam of radiation, a support to support a patterning device to impart a pattern on the beam, a projection system to project the patterned beam onto a substrate, and a metrology system that includes a radiation source to generate radiation, an optical element to direct the radiation toward a target, a detector to receive a first and second radiation scattered by the target and produce a first and second measurement respectively based on the received first and second radiation, and a controller. The controller determines a correction for the first measurement, an error between the correction for the first measurement and the first measurement, and a correction for the second measurement based on the correction for the first measurement, the second measurement, and the error. The lithographic apparatus uses the correction to adjust a position of a substrate.

Systems, apparatuses, and methods are provided for determining the alignment of a substrate. An example method can include emitting a multi-wavelength radiation beam including a first wavelength and a second wavelength toward a region of a surface of a substrate. The example method can further include measuring a first diffracted radiation beam indicative of first order diffraction at the first wavelength in response to an irradiation of the region by the multi-wavelength radiation beam. The example method can further include measuring a second diffracted radiation beam indicative of first order diffraction at the second wavelength in response to the irradiation of the region by the multi-wavelength radiation beam. Subsequently, the example method can include generating, based on the measured first set of photons and the measured second set of photons, an electronic signal for use in determining an alignment position of the substrate.

The invention provides a position sensor (300) which comprises an optical system (305,306) configured to provide measurement radiation (304) to a substrate (307). The optical system is arranged to receive at least a portion of radiation (309) diffracted by a mark (308) provided on the substrate. A processor (313) is applied to derive at least one position-sensitive signal (312) from the received radiation. The measurement radiation comprises at least a first and a second selected radiation wavelength. The selection of the at least first and second radiation wavelengths is based on a position error swing-curve model.