# US 11,112,369 B2 · Hybrid overlay target design for imaging-based overlay and scatterometry-based overlay > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,112,369 B2 - Document ID: US11112369B2 - Status: Granted - Kind: B2 - Application number: 15/995,731 - Filed: 2018-06-01 - Published: 2018-12-20 - Granted: 2021-09-07 - Earliest claimed: 2017-06-19 - Assignees: KLA-Tencor Corporation - Applicants: Kla-Tencor Corporation - Inventors: David Gready - Web page: https://patentgrep.com/patent/US11112369B2 ## CPC - G01N 21/9501: {Semiconductor wafers (manufacturing processes per se of semiconductor devices implementing a measuring step H10P74/20)} - G01B 11/27: for testing the alignment of axes {(means for centering or aligning a light guide within a ferrule G02B6/3834)} - G01N 21/4788: {Diffraction (for sizing particles G01N15/0205)} - G01N 21/95607: {using a comparative method} - G03F 7/70633: {Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching} - G03F 7/70683: {Mark designs} - H10P 74/203: {Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects} - H10P 74/23: {characterised by multiple measurements, corrections, marking or sorting processes} - H10P 74/27: {Structural arrangements therefor} - G01N: INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES (measuring or testing apparatus or processes other than immunoassay, involving enzymes or microorganisms C12M, C12Q) - G01B: MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS - G03F: PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR; (phototypographic composing devices B41B; photosensitive materials or processes for photographic purposes G03C; electrophotography, sensitive layers or processes therefor G03G) - H10P: GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10 ## Abstract Designs for a hybrid overlay target design that includes a target area with both an imaging-based target and a scatterometry-based target are disclosed. The imaging-based overlay target design can include side-by-side grating structure. A scatterometry-based overlay target design at a different location in the target area can include grating-over-grating structure. A method of measuring the hybrid overlay target design and a system with both an imaging optical system and a scatterometry system for measuring the hybrid overlay target design are also disclosed. ## Claims ### Claim 1 A method comprising: acquiring a region of a wafer on a chuck with an overlay target on a surface of the wafer in the region using an imaging optical system thereby forming an acquired image, wherein the overlay target includes gratings in an imaging-based overlay target design and gratings in a scatterometry-based overlay target design, wherein the gratings in the imaging-based overlay target design are in a side-by-side configuration, and wherein the gratings in the scatterometry-based overlay target design are in a grating-over-grating configuration; measuring the overlay target with a first illumination beam from the imaging optical system using the acquired image; and measuring the overlay target with a second illumination beam from the scatterometry system, wherein the imaging-based overlay target design and the scatterometry-based overlay target design are in a same field of view during the measuring with the first illumination beam and the second illumination beam. ### Claim 2 (depends on 1) The method of claim 1, wherein the measuring with the scatterometry system is prior to the measuring with the imaging optical system. ### Claim 3 (depends on 1) The method of claim 1, wherein the scatterometry-based overlay target design has a different critical dimension compared to the imaging-based overlay target design. ### Claim 4 (depends on 1) The method of claim 1, wherein the imaging-based overlay target design and the scatterometry-based overlay target design are each disposed on two adjacent layers of the overlay target. ### Claim 5 (depends on 4) The method of claim 4, wherein a pattern for the imaging-based overlay target design on one of the two adjacent layers is different from the imaging-based overlay target design on another of the two adjacent layers. ### Claim 6 (depends on 1) The method of claim 1, wherein the imaging-based overlay target design and the scatterometry-based overlay target design are in a cell of the overlay target and are oriented along a common axis of orientation, wherein there are a plurality of the cells on the overlay target, and wherein at two of the sections have axes of orientation that are perpendicular to each other. ### Claim 7 (depends on 1) The method of claim 1, wherein the measuring with the imaging optical system and the measuring with the scatterometry system occur at least partially simultaneously. ### Claim 8 A system comprising: a chuck configured to hold a wafer having an overlay target on a surface of the wafer, wherein the overlay target includes gratings in an imaging-based overlay target design and gratings in a scatterometry-based overlay target design, wherein the gratings in the imaging-based overlay target design are in a side-by-side configuration, and wherein the gratings in the scatterometry-based overlay target design are in a grating-over-grating configuration; an imaging optical system with a first illumination source configured to measure the overlay target on the chuck; a scatterometry system with a second illumination source configured to measure the overlay target on the chuck; and a processor in electronic communication with the imaging optical system and the scatterometry system, wherein the imaging optical system and the scatterometry system are configured to measure the same overlay target, wherein the imaging-based overlay target design and the scatterometry-based overlay target design are in a same field of view of the imaging optical system and the scatterometry system. ### Claim 9 (depends on 8) The system of claim 8, further comprising an imaging optical system acquisition module configured to acquire the overlay target on the chuck with the imaging optical system thereby forming an acquired image, and wherein the imaging optical system uses the acquired image. ### Claim 10 (depends on 8) The system of claim 8, wherein the imaging optical system and the scatterometry system are configured to measure the overlay target at least partially simultaneously.