Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An illumination system delivers the electromagnetic radiation to an object plane. A source of a diffraction pattern is in the object plane. A projection optical system projects the diffraction pattern onto an image plane, which includes a mechanism (e.g., a shearing grating) to introduce the lateral shear. A detector is located optically conjugate with the pupil of the projection optical system, and receives an instant fringe pattern, resulting from the interference between sheared wavefronts, from the image plane. The diffraction pattern is dynamically scanned across a pupil of the projection optical system, and the resulting time-integrated interferogram obtained from the detector is used to measure the wavefront aberration across the entire pupil.

Abstract: A method for measuring a wavefront of an optical system. A first step of the method includes directing electromagnetic radiation uniformly at an object plane having a first grating positioned therein. Lines of the first grating comprise a plurality of dots. A second step of the method includes projecting an image of the first grating onto a focal plane having a second grating positioned therein. A third step of the method includes measuring the wavefront of the optical system based on a fringe pattern produced by the second grating.

Abstract: A grating includes an absorptive substrate and a plurality of reflective lines on the absorptive substrate. Each reflective line is formed by a plurality of reflective areas. The reflective areas can be arranged in a regular pattern. The reflective areas are between 70 nm and 120 nm in diameter. The reflective areas can be circular. The reflective areas can have a random height distribution.

Abstract: A method and system as used to calibrate a reflective SLM. The system can include the SLM having an array of pixels and a projection optical system resolving individual pixels and having an apodized pupil. During a calibration operation, the pixels of the SLM receive varying voltage values to move them through various angles. Light reflecting from the pixels during these movements forms individual images for each pixel at each angle. The light passes through the apodized pupil and is received on one or more sections of a detector. The apodization pattern is selected so that individual pixels remain well resolved with strong sensitivity to the pixel mirror tilt. The light intensity received for each pixel at each angle is correlated to the voltage value received at the pixel to tilt the pixel to that angle producing a result signal used by a control device to calibrate the SLM.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An illumination system delivers the electromagnetic radiation to an object plane. A source of a diffraction pattern is in the object plane. A projection optical system projects the diffraction pattern onto an image plane, which includes a mechanism (e.g., a shearing grating) to introduce the lateral shear. A detector is located optically conjugate with the pupil of the projection optical system, and receives an instant fringe pattern, resulting from the interference between sheared wavefronts, from the image plane. The diffraction pattern is dynamically scanned across a pupil of the projection optical system, and the resulting time-integrated interferogram obtained from the detector is used to measure the wavefront aberration across the entire pupil.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An imaging system directs the electromagnetic radiation at an object plane that it uniformly illuminates. A first grating is positioned in the object plane to condition the radiation entering the input of a projection optic. A projection optical system projects an image of the first grating onto the focal plane. A second grating is positioned at the focal plane that receives a diffracted image of the object plane to form a shearing interferometer. A CCD detector receives the image of the pupil of the projection optical system through the projection optical system and the second grating that forms a fringe pattern if there are aberrations in the projection optical system. Phaseshift readout of fringe pattern can be accomplished by stepping the first grating in a lateral direction and reading each frame with the CCD detector.

Abstract: A system for calibrating a spatial light modulator array includes an illumination system and a spatial light modulator array that reflects or transmits light from the illumination system. A projection optical system images the spatial light modulator array onto an image plane. A shearing interferometer creates an interference pattern in the image plane. A controller controls modulation of elements of the spatial light modulator array. The shearing interferometer includes a diffraction grating, a prism, a folding mirror or any other arrangement for generating shear. The shearing interferometer can be a stretching shearing interferometer, a lateral shearing interferometer, or a rotational shearing interferometer. The shearing interferometer may include a diffraction grating with a pitch corresponding to a shear of the light by an integer number of elements. The projection optics resolves each element of the spatial light modulator array in the image plane.

Abstract: The present invention provides systems and methods for maskless lithographic printing that compensate for static and/or dynamic misalignments and deformations. In an embodiment, a misalignment of a pattern formed by a spatial light modulator is measuring during printing. Rasterizer input data is generated based on the measured misalignment and passed the rasterizer. The rasterizer generates pattern data, based on the rasterizer input data, that is adjusted to compensate for the measured misalignment. The pattern data generated by the rasterizer is passed to the spatial light modulator and used to form a second pattern, which includes compensation for the measured misalignment. In an embodiment, deformations caused, for example, by a warping a surface of the spatial light modulator are measured and used by the rasterizer to generate pattern data that compensates for the deformations.

Abstract: A system for calibrating a spatial light modulator array includes an illumination system and a spatial light modulator array that reflects or transmits light from the illumination system. A projection optical system images the spatial light modulator array onto an image plane. A shearing interferometer creates an interference pattern in the image plane. A controller controls modulation of elements of the spatial light modulator array. The shearing interferometer includes a diffraction grating, a prism, a folding mirror or any other arrangement for generating shear. The shearing interferometer can be a stretching shearing interferometer, a lateral shearing interferometer, or a rotational shearing interferometer. The shearing interferometer may include a diffraction grating with a pitch corresponding to a shear of the light by an integer number of elements. The projection optics resolves each element of the spatial light modulator array in the image plane.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An imaging system directs the electromagnetic radiation at an object plane that it uniformly illuminates. A first grating is positioned in the object plane to condition the radiation entering the input of a projection optic. A projection optical system projects an image of the first grating onto the focal plane. A second grating is positioned at the focal plane that receives a diffracted image of the source to form a shearing interferometer. A CCD detector receives the image of the first grating through the projection optical system and the second grating that forms a fringe pattern if there are aberrations in the projection optical system. Phaseshift readout of fringe pattern can be accomplished by stepping the first grating in a lateral direction and reading each frame with the CCD detector. The first grating includes a plurality of reflecting lines each formed by a plurality of reflecting dots.

Abstract: A system for calibrating a spatial light modulator array includes an illumination system and a spatial light modulator array that reflects or transmits light from the illumination system. A projection optical system images the spatial light modulator array onto an image plane. A shearing interferometer creates an interference pattern in the image plane. A controller controls modulation of elements of the spatial light modulator array. The shearing interferometer includes a diffraction grating, a prism, a folding mirror or any other arrangement for generating shear. The shearing interferometer can be a stretching shearing interferometer, a lateral shearing interferometer, or a rotational shearing interferometer. The shearing interferometer may include a diffraction grating with a pitch corresponding to a shear of the light by an integer number of elements. The projection optics resolves each element of the spatial light modulator array in the image plane.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An imaging system directs the electromagnetic radiation at an object plane that it uniformly illuminates. A first grating is positioned in the object plane to condition the radiation entering the input of a projection optic. A projection optical system projects an image of the first grating onto the focal plane. A second grating is positioned at the focal plane that receives a diffracted image of the object plane to form a shearing interferometer. A CCD detector receives the image of the pupil of the projection optical system through the projection optical system and the second grating that forms a fringe pattern if there are aberrations in the projection optical system. Phaseshift readout of fringe pattern can be accomplished by stepping the first grating in a lateral direction and reading each frame with the CCD detector.

Abstract: A wavefront measurement system includes a source of electromagnetic radiation. An imaging system directs the electromagnetic radiation at an object plane that it uniformly illuminates. A first grating is positioned in the object plane to condition the radiation entering the input of a projection optic. A projection optical system projects an image of the first grating onto the focal plane. A second grating is positioned at the focal plane that receives a diffracted image of the source to form a shearing interferometer. A CCD detector receives the image of the first grating through the projection optical system and the second grating that forms a fringe pattern if there are aberrations in the projection optical system. Phaseshift readout of fringe pattern can be accomplished by stepping the first grating in a lateral direction and reading each frame with the CCD detector. The first grating includes a plurality of reflecting lines each formed by a plurality of reflecting dots.

Abstract: A method for co-registering a semiconductor wafer (14) undergoing work in one or more blind process modules (10), (12) requires a means (16), (18) for consistently and repeatably registering the semiconductor wafer (14) to each process module (10), (12). Given this consistent and repeatable singular wafer registration means (16), (18), the location of the coordinate axes of each process module (10), (12) is determined with respect to the position of the semiconductor wafer (14) that is registered therein.

Abstract: A system is provided for processing wafers, such as silicon and silicon-on-insulator wafers. The processing includes thinning and flattening of the wafers at a work station located directly beneath a down looking metrology apparatus for directing light onto the wafer and measuring the light wavefronts reflected from the wafer. The metrology apparatus for flattening includes the feature of a multiple lens array for arranging the reflected wavefronts into a plurality of light spots, and a charge-coupled-device light responsive device for receiving the light spots and determining the shape of the wavefronts. The system also provides a wafer transport system for moving one or more wafers into one or more work stations beneath the metrology apparatus in a vacuum chamber.

Abstract: A method for controlling the flow of semiconductor wafers within a semiconductor wafer processing facility. This method includes a wafer storage and preparation area (10) and a wafer metrology and etch area (12), both of which are monitored and/or controlled by a master controller (14). The wafer storage and preparation area (10) is typically kept at a class 10 clean room level and is comprised of a wafer storage area (16) and a wafer preparation area (18). The wafer metrology and etch area (12) is typically kept at a class 1000 clean room level and is comprised of an I/O cassette module (22), a wafer pre-aligner (24), a wafer router (26), a wafer metrology instrument (28), and a wafer etching instrument (30). The semiconductor wafers are transported, either manually or automatically, between the wafer storage area (16) and the wafer preparation area (18), as well as between the wafer storage and preparation area (10) and the wafer metrology and etch area (12), within wafer storage cassettes ( 20).

Abstract: A very wide spectral coverage grating spectrometer which gathers light from a scene being viewed and collimates that light. A mosaic grating is disposed in collimated space which disperses the collimated light. The dispersed light is focused onto a detector array.

Abstract: An apparatus for determining the fluorescence of materials in a scene which includes optical means to collect radiation from the scene. Means are provided to divide the collected radiation into first and second beam paths. The first beam path traverses a first filter centered on a Fraunhofer line and having a passband which extends into the solar continuum on either side of the Fraunhofer line. The second beam path traverses the first filter and a second filter, also centered on the Fraunhofer line, with a passband on the order of half the bandwidth, at half-depth, of the Fraunhofer line. Means are provided to image the first and second beams onto first and second detector arrays, respectively. The image on the first detector array is registered with the image on the second detector array. Co-adding means are provided whereby successive detector pixels at successive time intervals corresponding to a single point on the ground are added and averaged.

Abstract: An apparatus for the detection of fluorescence. An airborne optical system carried in an aircraft or spaceship scans a sunlit swath of terrain over a field of view defined by a selected one of the fringe rings of a Fabry-Perot etalon designed to pass a selected Fraunhofer line. A first series of detectors are disposed to sense light intensity over a predetermined arc within said selected ring. A second like series of detectors are disposed to sense light intensity just outside said selected ring. Electronic means are connected to said first and second plurality of detectors for determining the fluorescence reflected from the swath of terrain.