Patent application number | Description | Published |
20080266561 | OPTICAL GAIN APPROACH FOR ENHANCEMENT OF OVERLAY AND ALIGNMENT SYSTEMS PERFORMANCE - A resultant image of a grating target may be obtained by dividing an image of the target into first and second portions and optically modifying the first and/or second portion such that a final image formed from their combination is characterized by a Moiré pattern. The resultant image may be analyzed to determine a shift in the grating target from a shift in the Moiré pattern. Optical alignment apparatus may include a first beam splitter, an image transformation element optically coupled to the first beam splitter, and a second beam splitter. The first beam splitter divides an image of a grating target into first and second portions. The second beam splitter combines the first portion and the second portion. The image transformation element optically modifies the first and/or second portion such that a final image formed from their combination is characterized by a Moiré pattern. | 10-30-2008 |
20090279091 | TARGET DESIGN AND METHODS FOR SCATTEROMETRY OVERLAY DETERMINATION - Disclosed are methods and apparatus for determining overlay error. Radiation that is scattered from each of a plurality of cells of a target is measured. Each cell includes at least a first grating structure formed by a first process and a second grating structure formed by a second process and wherein each cell has a predefined offset between such each cell's first and second grating structures. The first and second grating structures of the different cells have different predefined offsets, and each predefined offset of each cell is selected to cause one or more terms to be cancelled from a periodic function that represents radiation scattered and measured from each cell. The scattered radiation of each cell is represented with a periodic function having a plurality of unknowns parameters, including an unknown overlay error, and the unknown overlay error is determined based on the plurality of periodic functions for the plurality of cells. | 11-12-2009 |
20100155968 | Overlay Metrology Target - In one embodiment, a metrology target for determining a relative shift between two or more successive layers of a substrate may comprise; an first structure on a first layer of a substrate and an second structure on a successive layer to the first layer of the substrate arranged to determine relative shifts in alignment in both the x and y directions of the substrate by analyzing the first structure and second structure overlay. | 06-24-2010 |
20110228263 | ILLUMINATING A SPECIMEN FOR METROLOGY OR INSPECTION - Illumination subsystems of a metrology or inspection system, metrology systems, inspection systems, and methods for illuminating a specimen for metrology measurements or for inspection are provided. | 09-22-2011 |
20110279819 | ILLUMINATION SUBSYSTEMS OF A METROLOGY SYSTEM, METROLOGY SYSTEMS, AND METHODS FOR ILLUMINATING A SPECIMEN FOR METROLOGY MEASUREMENTS - Illumination subsystems of a metrology system, metrology systems, and methods for illuminating a specimen for metrology measurements are provided. | 11-17-2011 |
20110310388 | DISCRETE POLARIZATION SCATTEROMETRY - Systems and methods for discrete polarization scatterometry are provided. | 12-22-2011 |
20120033215 | MULTI-LAYER OVERLAY METROLOGY TARGET AND COMPLIMENTARY OVERLAY METROLOGY MEASUREMENT SYSTEMS - A multi-layer overlay target for use in imaging based metrology is disclosed. The overlay target includes a plurality of target structures including three or more target structures, each target structure including a set of two or more pattern elements, wherein the target structures are configured to share a common center of symmetry upon alignment of the target structures, each target structure being invariant to N degree rotation about the common center of symmetry, wherein N is equal to or greater than 180 degrees, wherein each of the two or more pattern elements has an individual center of symmetry, wherein each of the two or more pattern elements of each target structure is invariant to M degree rotation about the individual center of symmetry, wherein M is equal to or greater than 180 degrees. | 02-09-2012 |
20130035888 | METHOD AND SYSTEM FOR PROVIDING A QUALITY METRIC FOR IMPROVED PROCESS CONTROL - The present invention may include acquiring a plurality of overlay metrology measurement signals from a plurality of metrology targets distributed across one or more fields of a wafer of a lot of wafers, determining a plurality of overlay estimates for each of the plurality of overlay metrology measurement signals using a plurality of overlay algorithms, generating a plurality of overlay estimate distributions, and generating a first plurality of quality metrics utilizing the generated plurality of overlay estimate distributions, wherein each quality metric corresponds with one overlay estimate distribution of the generated plurality of overlay estimate distributions, each quality metric a function of a width of a corresponding generated overlay estimate distribution, each quality metric further being a function of asymmetry present in an overlay metrology measurement signal from an associated metrology target. | 02-07-2013 |
20130044331 | OVERLAY METROLOGY BY PUPIL PHASE ANALYSIS - The present invention may include measuring a first phase distribution across a pupil plane of a portion of illumination reflected from a first overlay target of a semiconductor wafer, wherein the first overlay target is fabricated to have a first intentional overlay, measuring a second phase distribution across the pupil plane of a portion of illumination reflected from a second overlay target, wherein the second overlay target is fabricated to have a second intentional overlay in a direction opposite to and having the same magnitude as the first intentional overlay, determining a first phase tilt associated with a sum of the first and second phase distributions, determining a second phase tilt associated with a difference between the first and second phase distributions, calibrating a set of phase tilt data, and determining a test overlay value associated with the first and second overlay target. | 02-21-2013 |
20130293890 | Overlay Targets with Orthogonal Underlayer Dummyfill - The disclosure is directed to designing and using an overlay target with orthogonal underlayer dummyfill. According to various embodiments, an overlay target may include one or more segmented overlay pattern elements forming at least one overlay target structure. The overlay target may further include one or more inactive pattern elements forming at least one dummyfill target structure. Each of the one or more inactive pattern elements may include dummyfill segmented along an axis orthogonal to a segmentation axis of at least one proximately disposed overlay pattern element. In some embodiments, each of the target structures or layers may be formed from a separate process layer successively disposed upon a substrate, such as a silicon wafer. In some embodiments, the overlay and dummyfill target structures may be twofold or fourfold rotationally symmetric to allow for certain manufacturing or metrology advantages. | 11-07-2013 |
20140141536 | Method and System for Providing a Target Design Displaying High Sensitivity to Scanner Focus Change - A segmented mask includes a set of cell structures, wherein each cell structure includes a set of features having an unresolvable segmentation pitch along a first direction, wherein the unresolvable segmentation pitch along the first direction is smaller than the illumination of the lithography printing tool, wherein the plurality of cell structures have a pitch along a second direction perpendicular to the first direction, wherein the unresolvable segmentation pitch is suitable for generating a printed pattern for shifting the best focus position of the lithography tool by a selected amount to achieve a selected level of focus sensitivity. | 05-22-2014 |