Abstract: Toric surfaces are mounted on a transparent support plate and measured at grazing incidence using a pair of leading and following diffractive optics for diffracting a test beam with respect to a reference beam. The leading diffractive optic diffracts rays of the test beam through various diffraction angles so that after passing through the transparent support plate, the rays strike the toric surface at a constant grazing angle. The following diffractive optic further diffracts the rays of the test beam through other diffraction angles into realignment with the reference beam.

Abstract: Compound diffractive optics are used in an interferometer for simultaneously measuring multiple surfaces, making multiple measurements of individual surfaces, conveying test beams multiple times, and aligning pairs of the diffractive optics with each other. Typically, the compound optics have multiple diffraction zones that reshape test beams for reflecting from test surfaces or for combining with reference beams. The multiple diffraction zones can also exhibit different optical qualities such as transmission and reflection for conveying the test beams to and from the test surfaces.

Abstract: An interferometer (10) employs diffractive optics (30 and 40) for measuring errors in test surfaces (14) that differ from planes and spheres. A beam of light (28) is separated into two portions (32 and 34). One of the diffractive optics (30) can be used to reshape the second portion (34) of a beam of light (28) into a form that is different than the first portion (32) along a path of grazing incidence to the test surface (14), and the other diffractive optic (40) can be used to further reshape the second portion (34) into a form in common with the first portion (32) of the beam of light (28). The two beam portions (32 and 34) are recombined to produce an interference pattern (44) representing the errors in the test surface (14).

Abstract: An interferometer (10) includes a prism extender (50) appended to a prism (32) for directing a beam of light (42) into a recess (44) of a test piece (34). A first portion (42a) of the beam (42) refracts from a reference surface (54) of the prism extender (50) to an angle (.alpha.) of grazing incidence on a bottom surface (46) of the recess (44), and a second portion (42b) of the beam (42) reflects from the reference surface (54). The two portions (42 aand 42b) of the beam (42) recombine at the reference surface (54) forming an interference pattern indicative of differences between the reference surface (54) and the bottom surface (46) of the recess (44).

Abstract: A mounting seat for an optical element is decoupled from a surrounding annulus that fixes the mount in place in an optical system. The annulus can be one of a plurality of annuli that are interconnected to surround and enclose a coaxial array of optical elements. The decoupling is accomplished by three flexible fingers extending inward from the annulus to a seat for the optical element, which can be mounted either directly on the flexible fingers or on a concentric seating ring supported by the fingers. The flexible elements can be formed integrally with an annulus by cutting slots in its inner perimeter. The flexible elements are structured relative to the lens elements they support so that natural frequencies of vibration of the lens elements are higher than the frequencies of external vibration.

Abstract: A mounting seat for an optical element is decoupled from a surrounding annulus that fixes the mount in place in an optical system. The annulus can be one of a plurality of annuli that are interconnected to surround and enclose a coaxial array of optical elements. The decoupling is accomplished by three flexible fingers extending inward from the annulus to a seat for the optical element, which can be mounted either directly on the flexible fingers or on a concentric seating ring supported by the fingers. The flexible elements can be formed integrally with an annulus by cutting slots in its inner perimeter. The flexible elements are structured relative to the lens elements they support so that natural frequencies of vibration of the lens elements are higher than the frequencies of external vibration.

Abstract: A Fizeau interferometer (10) producing spherical test and reference wavefronts (34 and 36) is operated with a linear translator (50) for making a sequence of subaperture measurements of an aspherical test surface (40). Separate phase maps (88 and 90) are assembled at different focus positions (54 and 56) along a common optical axis (52) of the interferometer (10) and aspherical test surface (40). Respective null zones (92 and 94) are isolated from the phase maps (88 and 90) and are combined to form a composite phase map (100) defining differences between the aspherical test surface (40) and a family of spheres.

Abstract: Optimum solutions for three-mirror lenses for projection lithography cameras using X-ray radiation to image a mask on a wafer are represented as single points within regions of two-dimensional magnification space defined by the magnification of a convex mirror as one coordinate and the ratio of the magnifications of a pair of concave mirrors optically on opposite sides of the convex mirror as another coordinate. Lenses within region 30, 50, and preferably within region 40, 60, of such magnification space represent potential solutions that are optimizable by standard computer optical design programs and techniques to achieve extremely low distortion lenses having a resolution of about 0.1 micron or less. Two of these lens systems having large chief ray angles at the mask and chief rays inclined away from the optical axis of the lens system in a direction from the source toward the mask are described in more detail.

Abstract: A mask or reticle for a single large microcircuit device is imaged in portions by an axially centered photolithographic reduction lens having a movable mask stage in addition to a movable wafer stage so that the portions of the complete device are imaged in juxtaposed registry on the wafer. This allows a single microcircuit device larger than the image field of the reduction lens to be imaged in a scanning mode or in a succession of steps forming images at the desired resolution range of 0.1-0.50 .mu.m.

Abstract: Optimum solutions for three-mirror lenses for projection lithography cameras using X-ray radiation to image a mask on a wafer are represented as single points within regions of two-dimensional magnification space defined by the magnification of a convex mirror as one coordinate and the ratio of the magnifications of a pair of concave mirrors optically on opposite sides of the convex mirror as another coordinate. Lenses within region 30, 50, and preferably within region 40, 60, of such magnification space represent potential solutions that are optimizable by standard computer optical design programs and techniques to achieve extremely low distortion lenses having a resolution of about 0.1 micron or less.

Abstract: A deep-UV step-and-repeat photolithography system includes a narrow-bandwidth pulsed excimer laser illumination source and an all-fused-silica lens assembly. The system is capable ofline definition at the 0.5-micrometer level. One significant feature of the system is its ability to perform wafer focus tracking by simply changing the frequency of the laser.

Abstract: Metrology for a microlithographic objective reducing lens 10 is integrated into a metrology block 20 secured to a lower region of the barrel 15 for lens 10. Block 20 has a central opening 27 around a lowermost element 11 of lens 10; and block 20 mounts distance detectors 28 around central opening 27, a pair of microscope objectives 30 and 31, and a pair of X and Y mirrors 40 and 41.

Abstract: A deep-UV step-and-repeat photolithography system includes a narrow-bandwidth pulsed excimer laser illumination source and an all-fused-silica lens assembly. The system is capable of line definition at the 0.5-micrometer level. One significant feature of the system is its ability to perform wafer focus tracking by simply changing the frequency of the laser.

Abstract: A deep-UV step-and-repeat photolithography system includes a narrow-bandwidth pulsed excimer laser illumination source and an all-fused-silica lens assembly. The system is capable of line definition at the 0.5-micrometer level. One significant feature of the system is its ability to perform wafer focus tracking by simply changing the frequency of the laser.

Abstract: A deep-UV step-and-repeat photolithography system includes a narrow-bandwidth pulsed excimer laser illumination source and an all-fused-silica lens assembly. The system is capable of line definition at the 0.5-micrometer level. One significant feature of the system is its ability to perform wafer focus tracking by simply changing the frequency of the laser.

Abstract: A method and an apparatus for continuously patterning a photosensitive tape or foil wherein a master pattern and the tape or foil are synchronously coupled. An optical system comprising a plano-convex lens, a concave spherical mirror, and a pair of right-angle prisms is optically-coupled between the master pattern and the tape or foil for projecting an image of the pattern onto the tape. The optical system is such that the movement of the image is in the same direction as the movement of the tape. The apparatus is such that patterning can take place through projecting an image on one or on both sides of the tape. Alternatively, projecting an image on one side of the tape and contact printing of a pattern on the other side of the tape is also made possible by the apparatus.

Abstract: A compact image projection apparatus comprises a concave spherical mirror, a plano-convex lens, a quarter wave plate and two prisms one of which is a roof prism. The apparatus is such that object and image have the same orientation and are positioned in two parallel planes. The apparatus is located, for example, between a mask and a semiconductor wafer in a scanning projection printing system.