Abstract: Extreme ultra-violet (EUV) lithography ruling engine specifically configured to print one-dimensional lines on a target workpiece includes source of EUV radiation; a pattern-source defining 1D pattern: an illumination unit (IU) configured to irradiate the pattern-source; and projection optics (PO) configured to optically image, with a reduction factor N>1, the 1D pattern on image surface that is optically-conjugate to the 1D pattern. Irradiation of the pattern-source can be on-axis or off-axis. While 1D pattern has first spatial frequency, its optical image has second spatial frequency that is at least twice the first spatial frequency. The pattern-source can be flat or curved. The IU may include a relay reflector. A PO's reflector may include multiple spatially-distinct reflecting elements aggregately forming such reflector. The engine is configured to not allow formation of optical image of any 2D pattern that has spatial resolution substantially equal to a pitch of the 1D pattern of the pattern-source.

Abstract: A new and useful illumination device, e.g. for a lithographic optical imaging system, is provided, and comprises a mirror array located between a radiation source and an illumination pupil. Each mirror element of the mirror array is individually steerable (controllable), and the polarization state of light from each mirror element of the mirror array can be selectively controlled, so that the illumination pupil can be filled with a distribution of light that is selectively controlled.

Abstract: Method of predicting a distribution of light in an illumination pupil of an illumination system includes identifying component(s) of the illumination system the adjustment of which affects this distribution and simulating the distribution based on a point spread function defined in part by the identified components. The point spread function has functional relationship with configurable setting of the illumination settings.

Abstract: Autofocus system (AF) employing, in addition to specified optical units, fringe projection and fringe detection systems (FPS, FDS) and specifically-configured data processing system. AFS is configured to project with FPS a sinusoidal fringe pattern, formed by a pattern source, on a substrate and to image the so projected pattern from substrate onto optical detector with FDS to form optical image from which topology of the substrate is defined as substrate moves relative to the projected pattern. Pattern source may include diffraction grating oriented that the projected pattern is inclined relative to direction of substrate scanning Topology profile is corrected for tilt of substrate, Goos-Hanchen errors, and for fringe-pattern-induced errors outside a chosen spatial-frequency range. To reduce errors of topology profile, at least five values of phase difference are used. AFS is configured to define temporal phase shifting in optical image without using any moving parts in the AFS.

Abstract: A new and useful illumination device, e.g. for a lithographic optical imaging system, is provided, and comprises a mirror array located between a radiation source and an illumination pupil. Each mirror element of the mirror array is individually steerable (controllable), and the polarization state of light from each mirror element of the mirror array can be selectively controlled, so that the illumination pupil can be filled with a distribution of light that is selectively controlled.

Abstract: An optical assembly for a system for inspecting or measuring of an object is provided that is configured to move as a unit with a system, as the system is pointed at a target, and eliminates the need for a large scanning (pointing) mirror that is moveable relative to other parts of the system. The optical assembly comprises catadioptric optics configured to fold the optical path of the pointing beam and measurement beam that are being directed through the outlet of the system, to compress the size of the optical assembly.

Abstract: Interrogation optical beams are focused or otherwise shaped for delivery to a target that includes one or more tooling balls so as to have a beam radius of curvature corresponding to a tooling ball radius. Focus values can be stored in a look-up table and can include two beam focus conditions that produce a selected beam focus. The two beam focus conditions are associated with a common beam curvature. The focus conditions are associated with beam curvatures within and without a Rayleigh range from a beam waist.

Abstract: Laser radar systems include focusing optical systems having a retroreflector such as a corner cube that is translatable with respect to an objective lens. The retroreflector provides a selected retardance to an interrogation optical beam that is directed to a target as well as to a returned portion of the interrogation optical beam that is directed to a detection system. Typically, an input linearly polarized interrogation beam is returned by the retroreflector as a circularly polarized beam that is directed to the target. Returned beam portions from the target are coupled by the retroreflector to a detection system in a linear polarization that is orthogonal to that of the input linearly polarized optical beam. The retroreflector produces state of polarization changes based on retardance associated with total internal reflection from coated or uncoated optical surfaces. Retroreflector surfaces that are not to introduce retardance are coated with suitable zero or low retardance coatings.

Abstract: Two dimensional encoder system and method designed to improve accuracy, compactness, stability, resolution, and/or light efficiency of metrology carried out with such system and method. Embodiments employ a novel retroreflector which while particularly useful in present invention, is believed to have more general utility in optical imaging systems and methods.

Abstract: Interferometer system and method for use in a level sensor of an exposure apparatus and autofocus system employing same. Operating either at a single or multiple wavelengths, the interferometric system employs two diffraction orders, formed by diffraction grating of the system, as reference and sample beams and is structured to ensure that only light contained in one of the two orders interacts with a wafer under test, thereby ensuring that no interference fringes are projected onto the sample. The diffraction grating is positioned such that its grooves are nominally perpendicular to the direction of wafer scan. Based on measurement data representing interference between reference and sample beams at the detector, a determination of change in position of the wafer in the sample arm is made with increased sensitivity and/or resolution.

Abstract: An autofocus (AF) system and method is provided that maps the topography of a substrate such as a semiconductor wafer, in a manner that corrects for Goos Hanchen (GH) effect. In addition, a new and useful detector is provided that is particularly useful in an AF system and method. The detector preferably has both color and polarization filtering integrally associated with the detector, so that polarization and color filtering is provided at the detector, on a pixel by pixel basis.

Abstract: An autofocus system and method designed to account for instabilities in the system, e.g. due to instabilities of system components (e.g. vibrating mirrors, optics, etc) and/or environmental effects such as refractive index changes of air due to temperature, atmospheric pressure, or humidity gradients, is provided. An autofocus beam is split into a reference beam component (the split off reference channel) and a measurement beam component, by a beam splitting optic located a predetermined distance from (and in predetermined orientation relative to) the substrate, to create a first space between the beam splitting optic and the substrate. A reflector is provided that is spaced from the beam splitting optic by the predetermined distance, to create a second space between the reflector and the beam splitting optic.

Abstract: Method of predicting a distribution of light in an illumination pupil of an illumination system includes identifying component(s) of the illumination system the adjustment of which affects this distribution and simulating the distribution based on a point spread function defined in part by the identified components. The point spread function has functional relationship with configurable setting of the illumination settings.

Abstract: A measurement system (22) for measuring the position of a work piece (28) includes a measurement grating (34) and an encoder head (36). The encoder head (36) directs a measurement beam (252) at the measurement grating (34), the measurement beam (252) having an oval shaped cross-section. The encoder head (36) includes a beam shape adjuster (256) positioned in the path of an input measurement beam (240) having a substantially circular cross-sectional shape that transforms the input measurement beam (240) to provide the measurement beam (252) having the oval shaped cross-section.

Abstract: Autofocus system (AF) employing, in addition to specified optical units, fringe projection and fringe detection systems (FPS, FDS) and specifically-configured data processing system. AFS is configured to project with FPS a sinusoidal fringe pattern, formed by a pattern source, on a substrate and to image the so projected pattern from substrate onto optical detector with FDS to form optical image from which topology of the substrate is defined as substrate moves relative to the projected pattern. Pattern source may include diffraction grating oriented that the projected pattern is inclined relative to direction of substrate scanning Topology profile is corrected for tilt of substrate, Goos-Hanchen errors, and for fringe-pattern-induced errors outside a chosen spatial-frequency range. To reduce errors of topology profile, at least five values of phase difference are used. AFS is configured to define temporal phase shifting in optical image without using any moving parts in the AFS.

Abstract: Fringe-projection autofocus system devoid of a reference mirror. Contributions to error in determination of a target surface profile caused by air non-uniformities measured based on multiple measurements of the target surface performed at different wavelengths, and/or angles of incidence, and/or grating pitches and subtracted from the measured profile, rendering the system substantially insensitive to presence of air turbulence. Same optical beams forming a fringe irradiance pattern on target surface are used for measurement of the surface profile and reduction of measurement error by the amount attributed to air turbulence.

Abstract: Two dimensional encoder system and method designed to improve accuracy, compactness, stability, resolution, and/or light efficiency of metrology carried out with such system and method. Embodiments employ a novel retroreflector which while particularly useful in present invention, is believed to have more general utility in optical imaging systems and methods.

Abstract: An integrated optical assembly is provided, with enhancements that are particularly useful when the integrated optical assembly forms part of a laser radar system. The integrated optical assembly produces a reference beam that is related to the optical characteristics of a scanning reflector, or to changes in position or orientation of the scanning reflector relative to a source. Thus, if the scanning reflector orientation were to shift from its intended orientation (due e.g. to thermal expansion) or if characteristics of the scanning reflector (e.g. the index of refraction of the scanning reflector) were to change on account of temperature changes, the reference beam can be used to provide data that can be used to account for such changes. In addition, if the scanning reflector were to be positioned in an orientation other than the orientation desired, the reference beam can be used in identifying and correcting that positioning.

Abstract: A new and useful method is provided for Goos-Hanchen compensation in an optical autofocus (AF) system that uses light reflected from a substrate to determine changes in the z position of a substrate. According to the method of the invention reflected light from the substrate is provided at a plurality of wavelengths and polarizations, detected and used to make corrections that compensate for the errors due to the Goos-Hanchen effect.

Abstract: An encoder system and method are provided, that is designed to improve 2D encoder systems and methods in areas such as accuracy, compactness, stability, resolution, and/or light efficiency. Moreover, the system and method of this invention provides a new concept in a retroreflector that while particularly useful in applicants' system and method, is believed to have more general utility in optical imaging systems and methods.