Abstract: A wafer stage overlay error map is created using standard overlay targets and a special numerical algorithm. A reticle including a 2-dimensional array of standard overlay targets is exposed several times onto a photoresist coated silicon wafer using a photolithographic exposure tool. After exposure, the overlay targets are measured for placement error using a conventional overlay metrology tool. The resulting overlay error data is then supplied to a software program that generates a 2-dimensional wafer stage distortion and yaw overlay error map.

Abstract: A method and apparatus for determining lens distortion in a projection imaging tool are described. The techniques include exposing at least one alignment attribute onto a substrate having a recording media. A complementary alignment attribute is also exposed onto the substrate such that the complementary alignment attribute and alignment attribute form a completed alignment attribute. The exposure of the alignment attributes, or the complementary alignment attribute, or both, may be accomplished by multiple sub nominal dose exposures. Intra field distortion of the projection imaging tool is determined from measurements of the exposed completed alignment attributes. The alignment attributes and complimentary alignment attribute may be part of a reticle. The transmission of the alignment attribute may be different than the transmission of the complementary alignment attribute.

Abstract: An in-situ interferometer includes an image modifying optic that produces light ray bundles. The light ray bundles are projected onto a reticle with a plurality of measurement fiducials encoded onto a face of the reticle. The measurement fiducials are exposed onto a sensing plane and their locations measured. Aberrations in the projection system are determined from the measurements of the exposed reticles.

Abstract: A wafer stage overlay error map is created using standard overlay targets and a special numerical algorithm. A reticle including a 2-dimensional array of standard overlay targets is exposed several times onto a photoresist coated silicon wafer using a photolithographic exposure tool. After exposure, the overlay targets are measured for placement error using a conventional overlay metrology tool. The resulting overlay error data is then supplied to a software program that generates a 2-dimensional wafer stage distortion and yaw overlay error map.

Abstract: An apparatus and method for manufacturing and using a calibrated registration reference wafer in a semiconductor manufacturing facility where an archive media includes etched alignment attributes. Exposing a pattern of complementary alignment attributes onto the archive media such that the pattern of complementary alignment attributes overlay and interlock with the etched alignment attributes thereby forming completed alignment attributes. Then, measuring offsets in the completed alignment attributes and constructing a calibration file for the archive media based upon the offset measurements and other characteristic data of the exposure tool.

Abstract: A wafer stage overlay error map is created using standard overlay targets and a special numerical algorithm. A reticle including a 2-dimensional array of standard overlay targets is exposed several times onto a photoresist coated silicon wafer using a photolithographic exposure tool. After exposure, the overlay targets are measured for placement error using a conventional overlay metrology tool. The resulting overlay error data is then supplied to a software program that generates a 2-dimensional wafer stage distortion and yaw overlay error map.

Abstract: An apparatus and method for the simultaneous determination of focus and source boresighting error for photolithographic steppers and scanners is described. A reticle containing custom arrays of box-in-box test structures specifically designed for performing source or exit pupil division using an aperture plate is exposed onto a resist coated wafer several times. The resulting exposure patterns are measured with a conventional overlay tool. The overlay data is processed with a slope-shift algorithm for the simultaneous determination of both focus and source telecentricity as a function of field position. Additionally, methods for ameliorating metrology induced effects and methods for producing precision Bossung curves are also described. This Abstract is provided for the sole purpose of complying with the Abstract requirement rules, it shall not be used to interpret or to limit the scope or the meaning of the claims.

Abstract: A method and apparatus for determining lens distortion in a projection imaging tool are described. The techniques include exposing at least one alignment attribute onto a substrate having a recording media. A complementary alignment attribute is also exposed onto the substrate such that the complementary alignment attribute and alignment attribute form a completed alignment attribute. The exposure of the alignment attributes, or the complementary alignment attribute, or both, may be accomplished by multiple sub nominal dose exposures. Intra field distortion of the projection imaging tool is determined from measurements of the exposed completed alignment attributes. The alignment attributes and complimentary alignment attribute may be part of a reticle. The transmission of the alignment attribute may be different than the transmission of the complementary alignment attribute.

Abstract: A method and apparatus for determining lens distortion in a projection imaging tool are described. The techniques include exposing at least one alignment attribute onto a substrate having a recording media. A complementary alignment attribute is also exposed onto the substrate such that the complementary alignment attribute and alignment attribute form a completed alignment attribute. The exposure of the alignment attributes, or the complementary alignment attribute, or both, may be accomplished by multiple sub nominal dose exposures. Intra field distortion of the projection imaging tool is determined from measurements of the exposed completed alignment attributes. The alignment attributes and complimentary alignment attribute may be part of a reticle. The transmission of the alignment attribute may be different than the transmission of the complementary alignment attribute.

Abstract: An apparatus and method for manufacturing and using a calibrated registration reference wafer in a semiconductor manufacturing facility where an archive media includes etched alignment attributes. Exposing a pattern of complementary alignment attributes onto the archive media such that the pattern of complementary alignment attributes overlay and interlock with the etched alignment attributes thereby forming completed alignment attributes. Then, measuring offsets in the completed alignment attributes and constructing a calibration file for the archive media based upon the offset measurements and other characteristic data of the exposure tool.

Abstract: A process for the determination of focal plane deviation uniquely due to the scanning dynamics associated with a photolithographic scanner is described. A series of lithographic exposures is performed on a resist coated silicon wafer using a photolithographic scanner. The lithographic exposures produce an array of focusing fiducials that are displaced relative to each other in a unique way. The resulting measurements are fed into a computer algorithm that calculates the dynamic scanning field curvature in an absolute sense in the presence of wafer height variation and other wafer/reticle stage irregularities. The dynamic scan field curvature can be used to improve lithographic modeling, overlay modeling, and advanced process control techniques related to scanner stage dynamics.

Abstract: An apparatus and method for manufacturing and using a calibrated registration reference wafer in a semiconductor manufacturing facility. A reference reticle consisting of a 2-dimensional array of standard alignment attributes is exposed several times onto a photoresist coated semiconductor wafer using a photolithographic exposure tool. After the final steps of the lithographic development process the resist patterned wafer is physically etched using standard techniques to create a permanent record of the alignment attribute exposure pattern. The permanently recorded alignment attributes are measured for placement error using a conventional overlay metrology tool. The resulting overlay error data is used to generate a calibration file that contains the positions of the alignment attributes on the reference wafer. The reference wafer and calibration file can be used to determine the wafer stage registration performance for any photolithographic exposure tool.

Abstract: Methods and apparatus for correcting imaging defects, particularly focus defects induced by the lens or scan, in a projection imaging tool (PIT) are described. An illumination source is provided that can operate either simultaneously or alternately, at two or more discrete wavelength settings. The repeatable imaging defects of the PIT are measured. The cross field lens chromatic response is characterized at multiple discrete wavelength settings. Then, a compensating arrangement is designed tailored to compensate for the imaging defects and is used in the PIT.

Abstract: Intra-field distortion for a projection imaging tool is determined using a self-referenced rectangular grid reticle pattern, that includes at least two arrays of alignment attributes that are complementary to each other, is exposed multiple times onto a substrate with a recording media. A reference reticle pattern is exposed onto the substrate, wherein the reference reticle pattern overlaps the grid alignment attributes thereby creating completed grid alignment attributes. Positional offsets of the completed alignment attributes and completed grid alignment attributes are measured and an intra-field distortion from the offsets is determined.

Abstract: A method and apparatus for resolving both the angular (nx,ny) and spatial (x,y) dependence of the effective source coherence matrix for lithographic steppers and scanners is described. First an in-situ source metrology instrument is combined with in-situ polarization elements to create an in-situ source imaging polarizer or ISIP. The ISIP is loaded into a photolithographic exposure tool, aligned, and then exposed onto a suitable recording media or recording sensor. The recording sensor comprising either resist coated wafers or electronic sensors capture the image intensity at a multiplicity of different field points. The resulting measurements are entered into a computer program that reconstructs the source coherence matrix as a function of direction cosine at multiple field points. Alternative ISIP configurations are discussed in some detail. Applications of the ISIP include polarization source mapping for deep-UV and EUV lithography, process optimization, process monitoring, and chip manufacturing.

Abstract: A projection lens distortion error map is created using overlay targets and a special numerical algorithm. A reticle including an array of overlay targets is exposed several times onto a photoresist coated silicon wafer using a photolithographic stepper. After exposure, the overlay targets are measured for placement error. The resulting overlay error data is then supplied to a software program that generates a lens distortion error map for the photolithographic projection system.

Abstract: Determining corrections for a mask used in photolithography includes assembling characteristics of a mask design and an as-drawn specification into a virtual reticle. Assembling characteristics of machine subsystem parameters into a virtual wafer. Emulating machine performance on the virtual reticle and virtual wafer and accumulating the results in an updated virtual wafer. Comparing metrics of the updated virtual wafer to the as-drawn specification and if the comparison meets or exceeds a desired threshold, then incorporating mask clips of the virtual reticle into a final mask design, if the comparison does not meet the desired threshold, then calculating mask corrections, updating the virtual reticle, and repeating emulating and comparing.

Abstract: Exit pupil and source telecentricity of a projection imaging tool system is determined. The system contains a light source, an optical imager, a reticle, a substrate, and a positioner. The light source is optically coupled to the optical imager, the optical imager having an exit pupil. The combination of the light source and the optical imager define a projection imaging tool, are characterized by a partial coherence. The reticle has an array of patterns, each pattern having at least a first feature and a second feature. A substrate may be used to record at least a first image and a second image of the features. The positioner is used to dispose the first image and the second image such that the first image has a first defocus and the second image has a second defocus different from the first defocus.

Abstract: A reticle stage grid and yaw in a projection imaging tool is determined by exposing a first portion of a reticle pattern onto a substrate with a recording media thereby producing a first exposure. The first portion of the reticle pattern includes at least two arrays of alignment attribute that have features complementary to each other. The reticle stage is then shifted and a second portion of the reticle pattern is exposed. The first and second exposures overlap and interlock to create completed alignment attributes. Measurements of positional offsets of the completed alignment attributes are used to determine the reticle stage grid and yaw.

Abstract: A method and apparatus for front to back substrate registration is described. Alignment characteristics of features on surfaces of substrates can be used to physically align substrates with a multiplicity of integrated alignment optics. Measurement of offsets of the integral alignment optics are used to compute registration data for use in calibration of the substrate global alignment.