Devices and methods for processing a radiation beam with coherence are disclosed. In one arrangement, an optical system receives a radiation beam with coherence. The radiation beam comprises components distributed over one or more radiation beam spatial modes. A waveguide supports a plurality of waveguide spatial modes. The optical system directs a plurality of the components of the radiation beam belonging to a common radiation beam spatial mode and having different frequencies onto the waveguide in such a way that each of the plurality of components couples to a different set of the waveguide spatial modes, each set comprising one or more of the waveguide spatial modes.

A pulse width expansion apparatus according to an aspect of the present disclosure includes a polarization beam splitter and a transfer optical system. The transfer optical system includes ?-wavelength and reflection mirror pairs. The ?-wavelength mirror pair include first and second ?-wavelength mirrors. The first ?-wavelength mirror provides ?-wavelength phase shift and reflects a pulse laser beam. The second ?-wavelength mirror provides ?-wavelength phase shift and reflects the pulse laser beam reflected by the first ?-wavelength mirror. The reflection mirror pair are disposed on an optical path before and after or between the ?-wavelength mirror pair. The transfer optical system transfers an image of an input pulse laser beam on the polarization beam splitter to the optical path between the ?-wavelength mirror pair at one-to-one magnification as a first transfer image and transfers the first transfer image to the polarization beam splitter at one-to-one magnification as a second transfer image.

An optical system comprising: an illumination system configured, to form a periodic illumination mode comprising radiation in a pupil plane of the optical system having a spatial intensity profile which is periodic in at least one direction, a measurement system configured to measure a dose of radiation which is received in an field plane of the optical system as a function of position in the field plane, and a controller configured to: select one or more spatial frequencies in the field plane at which variation in the received dose of radiation as a function of position is caused by speckle, and determine a measure of the variation of the received dose of radiation as a function of position at the selected one or more spatial frequencies, the measure of the variation in the received dose being indicative of speckle in the field plane.

A microlithography projection exposure apparatus includes illumination optics configured to illuminate object field points of an object field in an object plane, and projection optics configured to image the object field onto an image field in an image plane. The illumination optics includes a multi-mirror array which includes a plurality of mirrors configured to adjust an intensity distribution in exit pupils associated with the object field points. The illumination optics also includes an optical system configured to produce, via an incoherent superposition of illumination rays, a temporal modification of a temporal stabilization of an illumination of the multi-mirror array. The optical system includes a mirror which includes a mirror surface. In addition, the optical system includes an actuator configured to produce a tilt of at least a portion of the mirror surface.

Methods and apparatuses for measuring a plurality of structures formed on a substrate are disclosed. In one arrangement, a method includes obtaining data from a first measurement process. The first measurement process including individually measuring each of the plurality of structures to measure a first property of the structure. A second measurement process is used to measure a second property of each of the plurality of structures. The second measurement process includes illuminating each structure with radiation having a radiation property that is individually selected for that structure using the measured first property for the structure.

An illumination unit for lithographic exposure and a device for lithographic exposure are disclosed. In an embodiment the illumination unit includes a beam source, an electronically drivable beam deflection element for generating a temporally varying two-dimensional beam deflection, a collimation lens, a beam homogenizing element, a Fourier lens and a field lens.

Disclosed herein is a lighting optical system comprising: a light source having a plurality of light-emitting elements configured to emit light from light-emitting surfaces, respectively; a relay optical system configured to convert a luminous intensity distribution of light emitted from each of the light-emitting elements into an irradiance distribution and to superimpose a plurality of the irradiance distributions corresponding to the plurality of light-emitting elements on each other on a superimposed surface; an optical integrator having a plurality of wavefront splitting elements arranged in parallel to each other, the plurality of wavefront splitting elements being configured to wavefront split irradiated light through the relay optical system and to transmit the wavefront split light as a plurality of pencils of light rays; and a condenser optical system configured to superimpose the plurality of pencils of light rays on each other on a surface to be irradiated.

A method includes: producing a light beam made up of pulses having a wavelength in the deep ultraviolet range, each pulse having a first temporal coherence defined by a first temporal coherence length and each pulse being defined by a pulse duration; for one or more pulses, modulating the optical phase over the pulse duration of the pulse to produce a modified pulse having a second temporal coherence defined by a second temporal coherence length that is less than the first temporal coherence length of the pulse; forming a light beam of pulses at least from the modified pulses; and directing the formed light beam of pulses toward a substrate within a lithography exposure apparatus.

Techniques for controlling an optical system include accessing a measured value of a property of a particular pulse of a pulsed light beam emitted from the optical system, the property being related to an amount of coherence of the light beam; comparing the measured value of the property of the light beam to a target value of the property; determining whether to generate a control signal based on the comparison; and if a control signal is generated based on the comparison, adjusting the amount of coherence in the light beam by modifying an aspect of the optical system based on the control signal to reduce an amount of coherence of a pulse that is subsequent to the particular pulse.

An exposure apparatus transfers a pattern on a wafer by irradiating a reticle with an illumination light, and the pattern is formed on a pattern surface of the reticle. The exposure apparatus is provided with a reticle stage that moves holding the reticle, and a sensor that irradiates a measurement light on the pattern surface of the reticle held by the reticle stage and detects speckles from the pattern.