A method includes receiving a device design layout and a scribe line design layout surrounding the device design layout. The device design layout and the scribe line design layout are rotated in different directions. An optical proximity correction (OPC) process is performed on the rotated device design layout and the rotated scribe line design layout. A reticle includes the device design layout and the scribe line design layout is formed after performing the OPC process.

An optical diffraction component has a periodic grating structure profile. The diffraction structure levels are arranged so that a wavelength range around two different target wavelengths diffracted by the grating structure profile has radiation components with three different phases that interfere destructively with one another. Diffraction structure levels predefine a topography of a grating period of the grating structure profile that is repeated regularly along a period running direction. These include a neutral diffraction structure level, a positive diffraction structure level raised relative thereto, and a negative diffraction structure level lowered relative thereto. The neutral diffraction structure level has an extent along the period running direction which is less than 50% of the extent of the grating period. A difference between the two target wavelengths is less than 50%. The result is an optical diffraction component whose possibilities for use can be extended, for example, to stray light suppression.

An alignment system aligns a laser beam to a desired position in a reference plane and to a desired direction in the reference plane. The system diffracts the laser light into different diffraction orders that are projected onto a detection plane using different lenses. As the locations of the projections of the different diffraction orders in the detection plane respond differently to changes in position and in direction of the beam in the reference plane, the locations of the projections enable to determine how to adjust the beam so as to get the beam properly aligned. The diffraction and the projection can be implemented by a hologram.

An apparatus (60) for adjusting an intensity of radiation. The apparatus comprises a grating (61) for receiving a radiation beam (B.sub.a) and for directing at least a portion of the radiation beam in a first direction in the form of a first reflected radiation beam (B.sub.a0), and one or more first actuators operable to rotate the grating to adjust a grazing angle between the radiation beam and a surface of the grating so as to vary an intensity of the reflected radiation beam.

Disclosed is a method of optimizing within an inspection apparatus, the position and/or size (and therefore focus) of a measurement illumination spot relative to a target on a substrate. The method comprises detecting scattered radiation from at least the target resultant from illuminating the target, for different sizes and/or positions of said illumination spot relative to the target; and optimizing said position and/or size of the measurement illumination spot relative to the target based on a characteristic of the detected scattered radiation for the different sizes and/or positions of said illumination spot relative to the target.

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.

The present disclosure generally relates to lithography devices comprising an autofocus system. The autofocus system is configured to individually focus and adjust a plurality of digital micromirror devices. The autofocus system comprises a single light beam and a diffractive optical element configured to split the single light beam into two or more split beams. The two or more split beams are directed to a beam splitter. The two or more split beams are then reflected off the surface of a substrate to at least one position sensor. The position sensor is configured to measure the position of each of the two or more split beams. At least one digital micromirror device is then individually adjusted based on the measured position to adjust the focus of the at least one digital micromirror device with respect to surface height and tilt variations of the substrate.

An inspection apparatus or lithographic apparatus includes an optical system and a detector. The optical system includes a non-linear prismatic optic. The optical system is configured to receive zeroth and first diffraction order beams reflected from a diffraction target and separate first and second polarizations of each diffraction order beam. The detector is configured to simultaneously detect first and second polarizations of each of the zeroth and first diffraction order beams. Based on the detected first and second polarizations of one or more diffraction orders, an operational parameter of a lithographic apparatus can be adjusted to improve accuracy or precision in the lithographic apparatus. The optical system can include a plurality of non-linear prismatic optics. For example, the optical system can include a plurality of Wollaston prisms.

Disclosed herein is a method comprising: obtaining a plurality of measurement results from a pattern on a substrate respectively using a plurality of substrate measurement recipes, the substrate processed by a lithography process; reconstruct, using a computer, the pattern using the plurality of measurement results, to obtain a reconstructed pattern.

Disclosed is a method of measuring a target, and a metrology apparatus. In one arrangement the target comprises a layered structure. The layered structure has a first target structure in a first layer and a second target structure in a second layer. The method comprises illuminating the target with measurement radiation using an illumination profile in the illumination pupil (u) that is offset from an imaginary line (IL) in the illumination pupil passing through the optical axis, to allow propagation to a detection region of the detection pupil of an allowed order (v.sub.2, v.sub.4) of a predetermined diffraction order while limiting propagation to the detection region of an equal and opposite order (v.sub.1, v.sub.3) of that predetermined diffraction order. Scattered radiation of plural double-diffracted allowed diffraction orders (w.sub.2, w.sub.4) is detected. A characteristic of the lithographic process is calculated using the detected scattered radiation of the predetermined diffraction orders.