摘要:
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. The controller can modulate alternate columns of elements of the spatial light modulator array.
摘要:
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.
摘要:
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. The controller can modulate alternate columns of elements of the spatial light modulator array.
摘要:
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. The controller can modulate alternate columns of elements of the spatial light modulator array.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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. The present invention method provides three approaches for determining the location of these axes: (1) an absolute location of the axes, (2) a relative location of the axes using one blind process module (10) to measure the position of a pattern etched into the semiconductor wafer (14) with another blind process module (12), and (3) a relative location of the axes using one blind process module (10) to measure surface or layer thickness characteristics in the semiconductor wafer (14) as modified by wafer processing. Regardless of which approach is followed, the determination of the location of the coordinate axes in each process module (10), (12) is an effective co-registration of the semiconductor wafer (14).
摘要:
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.
摘要:
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.