Compound overlapping measurement target

Abstract

A metrology target includes a first set of pattern elements compatible with a first metrology mode along one or more directions and a second set of pattern elements compatible with a second metrology mode along one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements.

Description

[0001] Cross-reference to related applications

[0002] This application claims the benefit under 35 U.S.C. §119(e) of U.S. Provisional Patent Application Serial No. 62 / 967,951, filed on January 30, 2020, by Anna Golotsvan, Inna Steely-Tarshish, and Mark Ghinovker, entitled “COMBINED OPTICAL AND EOVL TARGET FOR BIASES CALIBRATION”; and U.S. Provisional Patent Application Serial No. 63 / 032,217, filed on May 29, 2020, by Anna Golotsvan, Inna Steely-Tarshish, and Mark Ghinovker, entitled “COMPOSITE OVERLAY METROLOGY TARGET.” Each of the aforementioned applications is incorporated herein by reference in its entirety. Technical Field

[0003] The present disclosure relates generally to overlay metering, and more particularly, to overlay metering using combined targets. Background Art

[0004] Overlay metrology targets are typically designed to provide diagnostic information about the alignment of multiple layers of a sample by characterizing an overlay target having a target feature positioned on a sample layer of interest. Furthermore, the overlay alignment of multiple layers is typically determined by aggregating overlay measurements of multiple overlay targets at various locations across the sample. However, the accuracy and / or repeatability of overlay measurements of an overlay target may be sensitive to the specific location on the sample or the specific characteristics of the target feature to be measured. For example, small-sized target features may require the use of a metrology system capable of achieving higher resolution for the sample target. In this regard, as chip sizes continue to shrink, many samples contain target features that can be resolved at different resolutions. Including various independent targets on a single sample can lead to undesirable mismatches across different layers of the sample. Therefore, it is desirable to provide a metrology target that is compatible with multiple metrology modes having different resolutions. Summary of the Invention

[0005] According to one or more illustrative embodiments of the present disclosure, a metrology target is disclosed. In one illustrative embodiment, the metrology target includes a first set of pattern elements compatible with a first metrology mode along one or more directions. In another illustrative embodiment, the metrology target includes a second set of pattern elements compatible with a second metrology mode along one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements.

[0006] According to one or more illustrative embodiments of the present disclosure, a system is disclosed. In one illustrative embodiment, the system includes one or more metrology subsystems configured to acquire one or more metrology signals from one or more metrology targets of a sample. In another illustrative embodiment, the one or more metrology subsystems include: an illumination source; one or more illumination elements configured to direct an illumination beam from the illumination source toward the sample; one or more detectors; and one or more projection elements configured to collect illumination emitted from the sample and direct the illumination toward the one or more detectors. In another illustrative embodiment, the system includes one or more controllers having one or more processors communicatively coupled to the one or more detectors. In another illustrative embodiment, the one or more processors are configured to execute a set of program instructions maintained in a memory, wherein the set of program instructions are configured to cause the one or more processors to: receive, from the one or more metrology subsystems operating in a first metrology mode, one or more signals indicating illumination emanating from a first set of pattern elements of one or more metrology targets of the sample; receive, from the one or more metrology subsystems operating in a second metrology mode, one or more signals indicating illumination emanating from a second set of pattern elements of the one or more metrology targets, wherein the one or more metrology targets of the sample include: the first set of pattern elements, wherein the first set of pattern elements are arranged along one or more directions; The method comprises: providing a first set of pattern elements compatible with the first metrology mode, and a second set of pattern elements, wherein the second set of pattern elements is compatible with the second metrology mode along one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements; determining one or more overlay parameters of the first set of pattern elements based on one or more signals obtained from the first set of pattern elements in the first metrology mode; and determining one or more overlay parameters of the second set of pattern elements based on the one or more signals obtained from the second set of pattern elements in the second metrology mode.

[0007] According to one or more illustrative embodiments of the present disclosure, a method for measuring overlay is disclosed. In one illustrative embodiment, the method for measuring overlay includes: illuminating a sample having one or more metrology targets; detecting illumination emitted from a first set of pattern elements of the one or more metrology targets of the sample in a first metrology mode; detecting illumination emitted from a second set of pattern elements of the one or more metrology targets of the sample in a second metrology mode; determining one or more overlay parameters of the first set of pattern elements based on the illumination emitted from the first set of pattern elements; and determining one or more overlay parameters of the second set of pattern elements based on the illumination emitted from the second set of pattern elements.

[0008] According to one or more embodiments of the present disclosure, a method for forming an overlay target is disclosed. In an illustrative embodiment, the method for forming an overlay target includes: forming a first set of pattern elements, wherein the first set of pattern elements is compatible with a first metrology mode along one or more directions; and forming a second set of pattern elements, wherein the second set of pattern elements is compatible with a second metrology mode along one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements.

[0009] It should be understood that both the foregoing summary and the following detailed description are exemplary and explanatory only and do not necessarily limit the invention as claimed.The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and together with the summary, serve to explain the principles of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Those skilled in the art may better understand the numerous advantages of the present disclosure by referring to the accompanying drawings.

[0011] Figure 1 is a top view of a metrology target according to one or more embodiments of the present disclosure.

[0012] Figure 2 is a top view of a metrology target according to one or more embodiments of the present disclosure.

[0013] Figure 3 is a top view of a metrology target according to one or more embodiments of the present disclosure.

[0014] Figure 4 is a top view of a metrology target according to one or more embodiments of the present disclosure.

[0015] Figure 5 is a top view of a metrology target according to one or more embodiments of the present disclosure.

[0016] Figure 6is a conceptual representation of a metrology target according to one or more embodiments of the present disclosure.

[0017] Figure 7 is a simplified block diagram of a metering system according to one or more embodiments of the present disclosure.

[0018] Figure 8A is a conceptual diagram illustrating a metering subsystem according to one or more embodiments of the present disclosure.

[0019] Figure 8B is a conceptual diagram illustrating a metering subsystem according to one or more embodiments of the present disclosure.

[0020] Figure 9 is a process flow diagram depicting steps of a method of measuring overlay according to one or more embodiments of the present disclosure.

[0021] Figure 10 is a process flow diagram depicting steps of a method of forming a metrology target according to one or more embodiments of the present disclosure. DETAILED DESCRIPTION

[0022] Reference will now be made in detail to the disclosed subject matter illustrated in the accompanying drawings. The present disclosure has been particularly shown and described with reference to certain embodiments and specific features thereof. The embodiments described herein are to be considered illustrative rather than restrictive. It will be readily apparent to those skilled in the art that various changes and modifications in form and details may be made without departing from the spirit and scope of the present disclosure.

[0023] Embodiments of the present disclosure relate to combined overlapping metrology targets that are compatible with one or more measurement modes.

[0024] It should be recognized herein that semiconductor devices can be formed as multiple printed layers of patterned material on a substrate. Each printed layer can be manufactured through a series of process steps, such as (but not limited to) one or more material deposition steps, one or more photolithography steps, or one or more etching steps. In addition, each printed layer must generally be manufactured within selected tolerances to properly construct the final device. For example, the relative placement (e.g., overlap or overlap parameters) of the printed elements in each layer must be well characterized and controlled relative to the previously manufactured layers. Therefore, metrology targets can be manufactured on one or more printed layers to enable effective characterization of the overlay of the layers. Thus, deviations in the overlay target features on a printed layer can represent deviations in the printed characteristics of the printed device features on that layer. Furthermore, overlay measured at one manufacturing step (e.g., after manufacturing one or more sample layers) can be used to generate a correctable term for accurately aligning process tools (e.g., photolithography tools or the like) used to manufacture additional sample layers in subsequent manufacturing steps.

[0025] The minimum feature size and feature density of the printed pattern in the lithography step are at least partially limited by the optical resolution of the projection optics of the lithography system. However, various lithography techniques can be used to produce features close to or below the resolution of the lithography system.

[0026] A metrology target may typically include well-defined printing elements designed to provide an accurate representation of one or more printing characteristics. In this regard, the measured characteristics of the printing elements of the metrology target (e.g., by a metrology tool) may represent printing device elements associated with the manufactured device. Furthermore, the metrology target is typically characterized as having one or more measurement cells, where each cell includes printing elements in one or more layers on the sample. Metrology measurements can then be based on any combination of measurements of the size, orientation, or position (e.g., pattern placement) of the printing elements in a single cell or between multiple cells. For example, one or more cells of an overlay metrology target may include printing elements on two or more sample layers arranged so that the relative position of the elements of each layer can indicate offset errors (e.g., pattern placement errors (PPE)) in a particular layer or overlay errors associated with registration errors between sample layers. By way of another example, a process-sensitive metrology target may include printed elements on a single sample layer, where one or more characteristics of the printed elements (e.g., width or critical dimension (CD), sidewall angle, position, or the like) are indicative of one or more process metrics, such as, but not limited to, the dose of illumination during a lithography step or the focal position of a sample in a lithography tool during a lithography step.

[0027] Overlay metrology is typically performed by fabricating one or more overlay targets across a sample, wherein each overlay target includes features in a sample layer of interest that were fabricated concurrently with features associated with a device or component being fabricated. In this regard, overlay errors measured at the locations of the overlay targets can represent overlay errors of device features. Thus, overlay measurements can be used to monitor and / or control any number of manufacturing tools to maintain production of devices according to specified tolerances. For example, overlay measurements of a current layer relative to a previous layer on a sample can be used as feedback data to monitor and / or mitigate manufacturing deviations of the current layer on additional samples within a batch. By way of another example, overlay measurements of a current layer relative to a previous layer on a sample can be used as feedforward data to fabricate subsequent layers on the same sample in a manner that takes into account the alignment of existing layers.

[0028] The overlay target typically includes features specifically designed to be sensitive to overlay errors between sample layers of interest.Overlay measurement can then be performed by characterizing the overlay target using an overlay metrology tool and applying an algorithm to determine the overlay error on the sample based on the output of the metrology tool.

[0029] Regardless of the overlay measurement technique, an overlay metrology tool can generally be configured according to a recipe that includes a set of measurement parameters for generating an overlay signal. For example, an overlay metrology tool recipe may include, but is not limited to: illumination wavelength, detected wavelength of radiation emitted from the sample, spot size of the illumination on the sample, angle of incident illumination, polarization of incident illumination, position of the incident illumination beam on an overlay target, position of the overlay target within the focal volume of the overlay metrology tool, or the like. Thus, an overlay recipe may include a set of measurement parameters for generating an overlay signal suitable for determining the overlay of two or more sample layers.

[0030] Overlay metrology tools can utilize various techniques to determine the overlay of sample layers. For example, image-based overlay metrology tools can illuminate an overlay target (e.g., an Advanced Imaging Metrology (AIM) target, a frame-in-frame metrology target, or the like) and capture an overlay signal comprising images of overlay target features located on different sample layers. Thus, overlay can be determined by measuring the relative positions of the overlay target features. By way of another example, scatterometry-based overlay metrology tools can illuminate an overlay target (e.g., a grating-on-grating metrology target, or the like) and capture an overlay signal comprising the angular distribution of radiation emitted from the overlay target associated with diffraction, scattering, and / or reflection of the illumination beam. Thus, overlay can be determined based on a model of the interaction of the illumination beam with the overlay target.

[0031] It should be recognized herein that various overlay metrology tools can be used to measure overlay. For example, optical metrology tools (e.g., light-based metrology tools that use electromagnetic radiation for illumination and / or detection) can provide high-throughput overlay measurements using a variety of techniques, such as, but not limited to, determining the relative positions of spatially separated features on multiple layers in an image, directly measuring the PPE on multiple layers, or scatterometry in which overlay is determined based on light scattered and / or diffracted from a diffraction grating on multiple layers. For the purposes of this disclosure, the terms "optical metrology tool," "optical metrology technique," and the like refer to metrology tools and techniques that use electromagnetic radiation of any wavelength, such as, but not limited to, x-ray wavelengths, extreme ultraviolet (EUV) wavelengths, vacuum ultraviolet (VUV) wavelengths, deep ultraviolet (DUV) wavelengths, ultraviolet (UV) wavelengths, visible wavelengths, or infrared (IR) wavelengths. However, depending on the wavelength of the illumination source, the resolution limitations of optical metrology tools often require feature sizes larger than device-level features, which can introduce systematic errors between optical metrology measurements and the actual overlay on the device features of interest. By way of another example, particle-based metrology tools, such as, but not limited to, scanning electron microscope (SEM) metrology tools (e.g., critical dimension SEM (CD-SEM) or the like), or focused ion beam (FIB) metrology tools, can resolve device-level features. Furthermore, particle beam metrology tools are limited in their ability to simultaneously measure features on multiple sample layers based on particle penetration depth. For example, a low-energy particle beam can be used to characterize a top layer (e.g., the current layer), while a relatively higher-energy particle beam can penetrate deeper into the sample to characterize features on previously fabricated layers. However, many particle-based metrology tools can have relatively lower throughput than optical metrology tools and can potentially cause damage to one or more layers during measurement. Systems, methods, and apparatus related to overlay measurement are generally described in the following cases: U.S. Patent No. 8,330,281, entitled “OVERLAY MARKS, METHODS OF OVERLAY MARK DESIGN AND METHODS OF OVERLAY MEASUREMENTS,” issued on December 11, 2012; U.S. Patent No. 9,476,698, entitled “PERIODIC PATTERNS AND TECHNIQUE TO CONTROL MISALIGNMENT BETWEEN TWO LAYERS,” issued on October 25, 2016;U.S. Patent No. 7,541,201, entitled “APPARATUS AND METHODS FOR DETERMINING OVERLAY OF STRUCTURES HAVING ROTATIONAL OR MIRROR SYMMETRY,” issued June 2, 2009; U.S. Patent Publication No. 2014 / 0169861, entitled “APPARATUS AND METHOD FOR DETECTING OVERLAY ERRORS USING SCATTEROMETRY,” published September 2, 2004; and U.S. Patent No. 2014 / 0169861, entitled “METHOD AND SYSTEM FOR PROVIDING A QUALITY METRIC FOR IMPROVED PROCESS CONTROL.” U.S. Patent No. 2013 / 0035888, entitled “SYSTEM AND METHOD OF SEM OVERLAY METROLOGY,” published on February 7, 2013; U.S. Patent No. 9,214,317, entitled “COMPOUND IMAGING METROLOGY TARGETS,” published on January 7, 2020; U.S. Patent No. 10,527,951B2, entitled “METROLOGY IMAGING TARGETS HAVING REFLECTION-SYMMETRIC PAIRS OF REFLECTION-ASYMMETRIC No. 10,190,979B2, issued January 29, 2019, entitled “APPARATUS AND METHOD FOR THE MEASUREMENT OF PATTERN PLACEMENT AND SIZE OF PATTERN AND COMPUTER PROGRAM THEREFOR,” filed June 27, 2016, all of which are incorporated herein by reference in their entirety.

[0032] As used throughout this disclosure, the term "sample" generally refers to a substrate (e.g., a wafer or the like) formed from semiconductor or non-semiconductor materials. For example, semiconductor or non-semiconductor materials may include, but are not limited to, single crystal silicon, gallium arsenide, and indium phosphide. A sample may include one or more layers. For example, such layers may include, but are not limited to, photoresist, dielectric materials, conductive materials, and semiconductor materials. Many different types of such layers are known in the art, and the term sample, as used herein, is intended to encompass samples on which all types of such layers may be formed. The one or more layers formed on a sample may be patterned or unpatterned. For example, a sample may include multiple dies, each having repeatable patterned features. The formation and processing of such material layers may ultimately result in a finished device. Many different types of devices may be formed on a sample, and the term sample, as used herein, is intended to encompass samples on which any type of device known in the art is fabricated. Furthermore, for the purposes of this disclosure, the terms sample and wafer shall be interpreted interchangeably. Furthermore, for the purposes of this disclosure, the terms patterned device, mask, and reticle shall be interpreted interchangeably.

[0033] Figure 1 1 is a top view of a metrology target 100 according to one or more embodiments of the present disclosure. In one embodiment, the metrology target 100 is doubly rotationally symmetric. The metrology target 100 may include a first set of pattern elements 102. The first set of pattern elements 102 includes a plurality of pattern elements. For example, the first set of pattern elements 102 may include, but is not limited to, pattern elements 106a through 106h. One or more of the pattern elements 106a through 106h may exhibit doubly rotational symmetry. Portions of the first set of pattern elements 102 may be formed at multiple layers of the metrology target 100. For example, pattern elements 106a, 106d, 106e, and 106h may be formed on a first layer of the metrology target 100 (e.g., as may be seen in FIG. 1 ). Figure 1 ), and pattern elements 106b, 106c, 106f, and 106g may be formed on the second layer of metrology target 100 (as may be seen by Figure 1 In this regard, the offset (e.g., PPE) of the first layer relative to the second layer of the metrology target 100 can be characterized by measuring the relative positions of pattern elements 106a-106h of the first set of pattern elements 102 positioned at different layers of the metrology target 100. One or more pattern elements 106a-106h can include one or more segmented portions (e.g., a repeating, periodic set of reference features).

[0034] In one embodiment, each layer of metrology target 100 may include two pattern elements 106a-106h configured for measurement along a first orthogonal direction (e.g., the X direction) and two pattern elements 106 configured for measurement along a second orthogonal direction (e.g., the Y direction). By way of additional example, the first layer of metrology target 100 may include pattern elements 106a and 106e configured for measurement along the Y direction. As an additional example, the first layer of metrology target 100 may include pattern elements 106d and 106h configured for measurement along the X direction. By way of another example, the second layer of metrology target may include pattern elements 106b and 106f configured for measurement along the Y direction, and pattern elements 106c and 106g configured for measurement along the X direction.

[0035] The first set of pattern elements 102 can be configured to be compatible with a first metrology scheme along one or more orthogonal directions (e.g., an X-direction and / or a Y-direction). For example, one or more pattern elements 106a-106h of the first set of pattern elements 102 can include edges defined along the X-direction and the Y-direction, such that the relative positions of the pattern elements 106a-106h of the first set of pattern elements can be readily measured (e.g., by one or more metrology subsystems or the like). As a further example, the first set of pattern elements 102 can be compatible with any optical metrology scheme known in the art suitable for the purposes contemplated by the present disclosure, including, but not limited to, Advanced Imaging Metrology (AIM), Advanced Imaging Metrology in Die (AIMid), and Triple Advanced Imaging Metrology (TripleAIM).

[0036] The metrology target 100 may include a second set of pattern elements 104 compatible with a second metrology mode. The second set of pattern elements 104 may include a first portion of the first set of pattern elements 102. The second set of pattern elements 104 may be surrounded by a second portion of the first set of pattern elements 102. In this regard, the second portion of the first set of pattern elements 102 is not included in the second set of pattern elements 104. For example, the second set of pattern elements 104 may include an inner portion of the first set of pattern elements 102 (e.g., Figure 1 104). The metrology target 100 can be configured so that the metrology target does not need to be moved to perform multiple metrology measurements in different metrology modes. For example, the first set of pattern elements 102 and the second set of pattern elements 104 can share a center point so that both the first metrology mode and the second metrology mode can be utilized at the common center point (e.g., by one or more metrology subsystems). In this way, the amount of time required to perform metrology measurements in at least two metrology modes can be reduced.

[0037] The second set of pattern elements 104 can be configured to be compatible with a second metrology mode along one or more orthogonal directions (e.g., an X-direction and / or a Y-direction). For example, one or more portions of pattern elements 106a-106h included in the second set of pattern elements 104 can include edges defined along the X-direction and the Y-direction, such that the relative positions of the one or more portions of pattern elements 106a-106h can be readily measured (e.g., by one or more metrology subsystems or the like). As a further example, the second set of pattern elements 104 can be compatible with any optical metrology mode or particle beam metrology mode known in the art suitable for the purposes contemplated by the present disclosure, including, but not limited to, Advanced Imaging In-Die Metrology (AIMid) and electron beam metrology.

[0038] It should be noted that while metrology target 100 is described in the context of example targets and pattern elements exhibiting two-fold symmetry, this feature should not be construed as limiting the scope of the present disclosure. Rather, it should be noted herein that target 100 and / or pattern elements 106a-106h can exhibit four-fold rotational symmetry.

[0039] Figure 2 is a top view of a metrology target 100 according to one or more embodiments of the present disclosure. The second set of pattern elements 104 can be configured such that additional edges along one or more orthogonal directions are included within the region of interest of the metrology target 100. For example, one or more portions of the second set of pattern elements 104 can include two or more segmented portions along one or more orthogonal directions of the metrology target 100. By way of further example, each of pattern elements 106b, 106d, 106f, and 106h can be formed such that the metrology target 100 is divided into two or more groups of segmented portions along one or more orthogonal directions. In this sense, the second set of pattern elements 104 can be configured for use on samples having smaller areas or smaller sample features. The second set of pattern elements 104 can allow the metrology target 100 to be compatible with various metrology subsystems and various metrology modes. For example, the second set of pattern elements 104 can allow the metrology target 100 to be used with two or more metrology subsystems having different resolutions. By way of another example, the second set of pattern elements 104 may allow the metrology target 100 to be used on samples having small dimensions and / or on samples having a dense array of sample features.

[0040] It should be noted that while metrology target 100 is described in the context of example targets and pattern elements exhibiting two-fold symmetry, this feature should not be construed as limiting the scope of the present disclosure. Rather, it should be noted herein that target 100 and / or second set of pattern elements 104 can exhibit four-fold rotational symmetry.

[0041] Figure 3FIG2 is a top view of a metrology target 100 according to one or more embodiments of the present disclosure. Metrology target 100 can have various sizes configured for use in close proximity to sample features. For example, metrology target 100 can be produced as an in-die metrology target (e.g., along a scribe street). By way of another example, metrology target 100 can be formed in-die based on sample design constraints, spacing, surrounding features, and the like. In this regard, metrology target 100 can be configured for use with any in-die metrology mode, including, but not limited to, AIMid.

[0042] Figure 4 is a top view of a metrology target 100 according to one or more embodiments of the present disclosure. The first set of pattern elements 102 may include one or more additional portions 402 configured to be compatible with one or more optical metrology modes. In one embodiment, the additional portions 402 are four-fold rotationally symmetric. The first set of pattern elements 102 may include one or more additional portions 402 configured for use with any optical metrology mode known in the art suitable for the purposes contemplated by the present disclosure, including, but not limited to, Triple AIM metrology. In one embodiment, the one or more additional portions 402 may be formed as one or more segmented portions at multiple layers of the metrology target 100. In another embodiment, the one or more additional portions 402 may be formed in a single layer on which neither any other portion of the first set of pattern elements 102 nor any portion of the second set of pattern elements 104 may be formed. In another embodiment, one or more portions of the one or more additional portions 402 may be formed on a layer on which one or more portions of the first set of pattern elements 102 and / or one or more portions of the second set of pattern elements are formed.

[0043] Figure 5 is a top view of a metrology target 100 according to one or more embodiments of the present disclosure. The metrology target 100 may include a third set of pattern elements 502 configured for use with a non-imaging metrology mode, such as a scatterometry-based overlay (SCOL) metrology mode. The third set of pattern elements 502 may include one or more alternating parallel gratings having equal spacing (e.g., separation distance). In one embodiment, the pattern elements of the third set of pattern elements 502 are two-fold rotationally symmetric. The third set of pattern elements 502 may be configured such that incident radiation directed thereto may be diffracted by the one or more alternating parallel gratings, and the diffracted radiation may be detected and analyzed (e.g., by one or more metrology subsystems) to determine one or more overlay parameters based on the angular distribution of the radiation.

[0044] The third set of pattern elements 502 may surround one or more portions of the first set of pattern elements 102. The third set of pattern elements 502 may be formed at multiple layers of the metrology target 100. For example, one or more pattern elements of the third set of pattern elements 502 may be formed on a first layer of the metrology target 100, and one or more pattern elements of the third set of pattern elements 502 may be formed on a second layer of the metrology target 100. The third set of pattern elements 502 may be configured to share the center of the metrology target 100 with the first set of pattern elements 102 and the second set of pattern elements 104. In this regard, the offset (e.g., PPE) of the first layer relative to the second layer of the metrology target 100 may be characterized by measuring the relative positions of the pattern elements of the third set of pattern elements 502 positioned at different layers of the metrology target 100.

[0045] It should be noted that while metrology target 100 is described in the context of example targets and pattern elements exhibiting four-fold symmetry, this feature should not be construed as limiting the scope of the present disclosure. Rather, it should be noted herein that target 100 and / or third set of pattern elements 502 can exhibit two-fold rotational symmetry.

[0046] Figure 6is a conceptual representation of a metrology target 100 according to one or more embodiments of the present disclosure. The metrology target 100 can be configured such that each of the first set of pattern elements 102, the second set of pattern elements 104, and the third set of pattern elements 502 are arranged and / or formed on a sample in a manner that takes into account one or more measurement parameters of the sample. For example, each of the first set of pattern elements 102, the second set of pattern elements 104, and the third set of pattern elements 502 can be arranged and / or formed on a sample to ensure that one or more metrology subsystems can accurately determine one or more overlay parameters of the sample (e.g., offset (PPE), scaling, rotation, and other correctable terms). By way of another example, all or some of the first set of pattern elements 102, the second set of pattern elements 104, or the third set of pattern elements 502 can be arranged such that one or more metrology modes can be used on one or more portions of the sample, where a different metrology mode (e.g., a metrology mode with a higher resolution) is necessary for accurate and desired metrology. It should be noted that the design of the metrology target 100 and the relative placement and / or formation of each of the first, second, and third set of pattern elements 102, 104, and 502 of the metrology target can be configured to correspond to one or more of the following: the wavelength of illumination of one or more subsystems configured for use with the metrology target 100, the wavelength of radiation emitted from the sample, the spot size of the illumination on the sample, the angle of the incident illumination, the polarization of the incident illumination, the position of the beam of incident illumination on the overlay target, the position of the overlay target within the focal volume of the overlay metrology tool, or the like. In this regard, the metrology target 100 can enable more efficient and accurate metrology of samples requiring multiple metrology modes. For example, the combination of the first, second, and / or third set of pattern elements 102, 104, and / or 502 in the metrology target 100 can enable one or more metrology recipes to be shared between one or more metrology subsystems operating in different metrology modes.

[0047] The metrology target 100 can be configured for use in the calibration of a metrology system. For example, the metrology target 100 can be used for signal processing (e.g., to include and analyze data related to the accuracy of metrology measurements made using different metrology modes) during in-die target measurements. By way of another example, the first and second set of pattern elements 102, 104 of the metrology target 100 can reduce target manufacturing inaccuracies caused by target placement and target architecture bias because the first, second, and third set of pattern elements 102, 104, and 502 share a common center.

[0048] Figure 7A simplified block diagram illustrates a metrology system 700 in accordance with one or more embodiments of the present disclosure. In one embodiment, the metrology system 700 includes one or more metrology subsystems 712. For example, the metrology system 700 may include a first metrology subsystem 702 and a second metrology subsystem 704, each of which may be configured to acquire an overlay signal from an overlay target based on any number of overlay recipes. Each of the first metrology subsystem 702 and the second metrology subsystem 704 may operate in an imaging mode or a non-imaging mode. For example, in the imaging mode, individual overlay target elements may be resolved within an illuminated spot on the sample (e.g., as part of a brightfield image, darkfield image, phase contrast image, or the like). By way of another example, each of the first metrology subsystem 702 and the second metrology subsystem 704 may operate as a scatterometry-based overlay (SCOL) metrology tool, in which radiation from the sample is analyzed at a pupil plane to characterize the angular distribution of the radiation from the sample (e.g., associated with scattering and / or diffraction of the radiation by the sample).

[0049] Each of the first metrology subsystem 702 and the second metrology subsystem 704 can direct illumination onto the sample and can further collect radiation emitted from the sample to generate an overlay signal suitable for determining overlay of two or more sample layers. Each of the first metrology subsystem 702 and the second metrology subsystem 704 can include any type of overlay metrology tool known in the art suitable for generating an overlay signal suitable for determining overlay associated with overlay targets on the sample, including but not limited to any optical metrology tool (e.g., an advanced imaging metrology (AIM) tool, an advanced imaging metrology in die (AIMid) tool, a triple advanced imaging metrology (Triple AIM) tool, and the like), any particle-based metrology tool (e.g., an electron beam metrology tool), or a scatterometry-based overlay (SCOL) metrology tool. It should be noted that embodiments of the present disclosure are not limited to a metrology system 700 having only a first metrology subsystem 702 and a second metrology subsystem 704, and the metrology system 700 can include at least three metrology subsystems. For example, the metrology system 700 may include optical metrology tools, particle-based metrology tools, and overlay metrology tools based on scatterometry.

[0050] The one or more metrology subsystems 712 can be configured to generate an overlay signal based on any number of recipes that define measurement parameters for acquiring an overlay signal suitable for determining overlay of an overlay target. For example, the recipes of the one or more metrology subsystems 712 can include, but are not limited to: illumination wavelength, detected wavelength of radiation emitted from the sample, spot size of the illumination on the sample, angle of incident illumination, polarization of incident illumination, wave plane profile of the incident beam, position of the beam of incident illumination on the overlay target, position of the overlay target in the focal volume of the overlay metrology tool, or the like.

[0051] In another embodiment, the overlay metering system 700 includes a controller 706 communicatively coupled to one or more metering subsystems 712. The controller 706 can be configured to direct the one or more metering subsystems 712 to generate an overlay signal based on one or more selected recipes. The controller 706 can further be configured to receive data (including, but not limited to, the overlay signal) from the one or more metering subsystems 712. Furthermore, the controller 706 can be configured to determine an overlay associated with an overlay target based on the acquired overlay signal.

[0052] In another embodiment, the controller 706 includes one or more processors 708. For example, the one or more processors 708 may be configured to execute a set of program instructions maintained in a memory device 710 or memory. The one or more processors 708 of the controller 706 may include any processing element known in the art. In this sense, the one or more processors 708 may include any microprocessor-type device configured to execute algorithms and / or instructions. In addition, the memory device 710 may include any storage medium known in the art suitable for storing program instructions executable by the associated one or more processors 708. For example, the memory device 710 may include a non-transitory memory medium. As additional examples, the memory device 710 may include, but is not limited to, read-only memory, random access memory, magnetic or optical storage devices (e.g., magnetic disks), tape, solid-state drives, and the like. It should be further noted that the memory device 710 may be housed in a common controller housing with the one or more processors 708.

[0053] Figure 8A FIG. 7 is a conceptual diagram illustrating a first metering subsystem 702 according to one or more embodiments of the present disclosure. Figure 8A As shown in and described previously in this disclosure, the first metrology subsystem 702 may include a particle-based metrology tool, such as an electron beam metrology tool (eg, a SEM, CD-SEM, or the like).

[0054] In one embodiment, the first metrology subsystem 702 includes a particle source 802 (e.g., an electron beam source, an ion beam source, or the like) for generating a particle beam 804 (e.g., an electron beam, a particle beam, or the like). The particle source 802 may include any particle source known in the art suitable for generating the particle beam 804. For example, the particle source 802 may include, but is not limited to, an electron gun or an ion gun. In another embodiment, the particle source 802 is configured to provide a particle beam having a tunable energy. For example, the particle source 802 including an electron source may, but is not limited to, provide an accelerating voltage in the range of 0.1 kV to 30 kV. As another example, the particle source 802 including an ion source may, but need not, provide an ion beam having an energy in the range of 1 keV to 50 keV.

[0055] In another embodiment, the first metrology subsystem 702 includes one or more particle-focusing elements 806. For example, the one or more particle-focusing elements 806 may include, but are not limited to, a single particle-focusing element or one or more particle-focusing elements forming a composite system. In another embodiment, the one or more particle-focusing elements 806 include a particle objective 808 configured to direct the particle beam 804 toward a sample 810 positioned on a sample stage 812. Furthermore, the one or more particle sources 802 may include any type of electron lens known in the art, including, but not limited to, an electrostatic lens, a magnetic lens, a unipotential lens, or a bipotential lens.

[0056] In another embodiment, the first metrology subsystem includes at least one particle detector 814 that images or otherwise detects particles emitted from the sample 810. In one embodiment, the particle detector 814 includes an electron collector (e.g., a secondary electron collector, a backscattered electron detector, or the like). In another embodiment, the particle detector 814 includes a photon detector (e.g., a photodetector, an x-ray detector, a scintillation element coupled to a photomultiplier tube (PMT) detector, or the like) for detecting electrons and / or photons from the sample surface.

[0057] It should be understood that Figure 8A The description of the first metrology subsystem 702 depicted in FIG and the associated description above is provided for illustrative purposes only and should not be construed as limiting. For example, the first metrology subsystem 702 may include a multi-beam and / or multi-column system suitable for simultaneously interrogating the sample 810. In further embodiments, the first metrology subsystem 702 may include one or more components (e.g., one or more electrodes) configured to apply one or more voltages to one or more locations on the sample 810. In this regard, the first metrology subsystem 702 may generate voltage contrast imaging data.

[0058] It should be appreciated herein that the penetration depth of particle beam 804 into sample 810 can depend on the particle energy, such that higher energy beams generally penetrate deeper into the sample. In one embodiment, first metrology subsystem 702 can utilize different particle energies to interrogate different layers of the device based on the penetration depth of particle beam 804 into sample 810. For example, first metrology subsystem 702 can utilize a relatively low energy electron beam (e.g., approximately 1 keV or less) and can utilize a higher energy beam (e.g., approximately 10 keV or greater) to characterize previously fabricated layers. It should be appreciated herein that the penetration depth that varies depending on particle energy can vary for different materials, such that the selection of particle energy for a particular layer can vary for different materials.

[0059] Figure 8BFIG. 7 is a conceptual diagram illustrating the second metering subsystem 704 according to one or more embodiments of the present disclosure. Figure 8B As shown in and previously described in this disclosure, the second metrology subsystem 704 can include an optical metrology tool. In one embodiment, the second metrology subsystem 704 can include any type of optical metrology tool known in the art suitable for generating metrology data for a sample, including, but not limited to, an optical metrology tool configured to generate and / or detect an optical illumination beam having an x-ray wavelength, an ultraviolet (UV) light wavelength, an infrared (IR) light wavelength, or a visible light wavelength. By way of another example, the second metrology subsystem 704 can include an advanced imaging metrology (AIM) tool, an advanced imaging metrology in die (AIMid) tool, or a triple advanced imaging metrology (Triple AIM) tool.

[0060] In one embodiment, the second metrology subsystem 704 includes an optical illumination source 816 configured to generate an optical illumination beam 818. The optical illumination beam 818 may include radiation of one or more selected wavelengths, including but not limited to x-rays, ultraviolet (UV) light, visible light, or infrared (IR) light.

[0061] Optical illumination source 816 may be any type of illumination source known in the art suitable for producing optical illumination beam 818 .

[0062] Optical illumination source 816 may include any type of illumination source suitable for providing optical illumination beam 818. In one embodiment, optical illumination source 816 is a laser source. For example, optical illumination source 816 may include, but is not limited to, one or more narrowband laser sources, broadband laser sources, supercontinuum laser sources, white light laser sources, or the like. In this regard, optical illumination source 816 may provide optical illumination beam 818 with high coherence (e.g., high spatial and / or temporal coherence). In another embodiment, optical illumination source 816 includes a laser-sustained plasma (LSP) source. For example, optical illumination source 816 may include, but is not limited to, an LSP lamp, an LSP bulb, or an LSP chamber suitable for housing one or more elements capable of emitting broadband illumination when excited into a plasma state by a laser source. In another embodiment, optical illumination source 816 includes a lamp source. For example, optical illumination source 816 may include, but is not limited to, an arc lamp, a discharge lamp, an electrodeless lamp, or the like. In this regard, the optical illumination source 816 may provide an optical illumination beam 818 having low coherence (eg, low spatial coherence and / or temporal coherence).

[0063] In another embodiment, an optical illumination source 816 directs an optical illumination beam 818 toward the sample 810 via an illumination path 820. The illumination path 820 may include one or more illumination path lenses 822 or additional optical components 824 suitable for modifying and / or adjusting the optical illumination beam 818. For example, the one or more optical components 824 may include, but are not limited to, one or more polarizers, one or more filters, one or more beam splitters, one or more diffusers, one or more homogenizers, one or more apodizers, or one or more beam shapers. The illumination path 820 may further include an objective lens 826 configured to direct the optical illumination beam 818 toward the sample 810.

[0064] In another embodiment, the sample 810 is disposed on a sample stage 812. The sample stage 812 can include any device suitable for positioning and / or scanning the sample 810 within the second metrology subsystem 704. For example, the sample stage 812 can include any combination of a linear translation stage, a rotation stage, a tilt / tilt stage, or the like.

[0065] In another embodiment, the second metrology subsystem 704 includes a detector 834 configured to capture light emitted from the sample 810 via a collection path 828. The collection path 828 may include, but is not limited to, one or more collection path lenses 836, 830 for collecting light from the sample 810. For example, the detector 834 may receive light reflected or scattered (e.g., via specular reflection, diffuse reflection, and the like) from the sample 810 via the one or more collection path lenses 836, 830. By way of another example, the detector 834 may receive light generated by the sample 810 (e.g., luminescence associated with absorption of the optical illumination beam 818, or the like). By way of another example, the detector 834 may receive light of one or more diffraction orders (e.g., 0th order, ±1st order, ±2nd order, and the like) from the sample 810.

[0066] Detector 834 may include any type of detector known in the art suitable for measuring illumination received from sample 810. For example, detector 834 may include, but is not limited to, a CCD detector, a TDI detector, a photomultiplier tube (PMT), an avalanche photodiode (APD), a complementary metal oxide semiconductor (CMOS) sensor, or the like. In another embodiment, detector 834 may include a spectral detector suitable for identifying the wavelength of light emitted from sample 810.

[0067] In one embodiment, the detector 834 is positioned approximately normal to the surface of the sample 810. In another embodiment, the second metrology subsystem 704 includes a light beam splitter oriented so that the objective lens 826 can simultaneously direct the optical illumination beam 818 to the sample 810 and collect light emitted from the sample 810. Furthermore, the illumination path 820 and the light collection path 828 can share one or more additional elements (e.g., the objective lens 826, an aperture, a filter, or the like).

[0068] Figure 9 A process flow diagram is illustrated depicting the steps of a method 900 of measuring overlay in accordance with one or more embodiments of the present disclosure.

[0069] At step 902, a sample having one or more metrology targets 100 is illuminated. For example, one or more metrology subsystems 712 may direct an illumination beam onto the sample 810. As used herein, the term "illumination beam" may refer to any radiation beam, including but not limited to a particle beam 804 and an optical illumination beam 818.

[0070] At step 904, illumination emanating from the first set of pattern elements 102 of the metrology target 100 is detected in a first metrology mode. For example, the optical illumination beam 818 may be detected by the detector 834 of the second metrology subsystem 704 configured as an optical metrology tool.

[0071] At step 906, illumination emitted from the second set of pattern elements 104 of the metrology target 100 is detected in a second metrology mode. For example, the particle beam 804 can be detected by a particle detector 814 of the first metrology subsystem 702 configured as a particle-based metrology tool.

[0072] In some embodiments, method 900 includes step 908 of detecting illumination emitted from a third set of pattern elements 502 of the metrology target 100 in a third metrology mode. For example, one of the one or more metrology subsystems 712 may detect radiation diffracted from the sample.

[0073] At step 910, one or more overlap parameters of the first set of pattern elements 102 of the metrology target 100 are determined. For example, the one or more processors 708 of the one or more controllers 706 may use an algorithm corresponding to a first metrology mode to analyze one or more signals indicative of illumination emitted from the first set of pattern elements 102. By way of another example, the one or more processors 708 may apply one or more algorithms (e.g., AIM, AIMid algorithm) to determine the one or more overlap parameters of the first set of pattern elements 102.

[0074] At step 912, one or more overlap parameters of the second set of pattern elements 104 of the metrology target 100 are determined. For example, the one or more processors 708 of the one or more controllers 706 may use an algorithm corresponding to the second metrology mode to analyze the one or more signals indicative of illumination emitted from the second set of pattern elements 104. By way of another example, the one or more processors 708 may apply one or more algorithms (e.g., a SEM characterization algorithm) to determine the one or more overlap parameters of the second set of pattern elements 104.

[0075] In some embodiments, the method 900 may include step 914, in which one or more overlap parameters of the third group of pattern elements 502 of the metrology target 100 are determined. For example, the one or more processors 708 may use an algorithm corresponding to the third metrology mode to analyze one or more signals indicative of illumination emitted from the third group of pattern elements 502. By way of another example, the one or more processors 708 may apply one or more algorithms (e.g., a SCOL-based algorithm) to determine the one or more overlap parameters of the third group of pattern elements 502.

[0076] In some embodiments, method 900 may include step 916, wherein one or more overlay correctable terms are provided based on the one or more overlay parameters determined in at least one of steps 910, 912, or 914. For example, step 916 may include controller 706 generating one or more control signals (or corrections to control signals) for adjusting one or more parameters (e.g., manufacturing settings, configuration, and the like) of one or more process tools (e.g., lithography tools). The control signals (or corrections to control signals) may be provided by controller 706 as part of a feedback and / or feedforward control loop. Controller 706 may cause one or more process tools to perform one or more adjustments to the one or more parameters of the one or more process tools based on the one or more control signals (or corrections to control signals). In some embodiments, controller 706 may alert a user to make the one or more adjustments. In this sense, the one or more control signals may compensate for errors in one or more processes of the one or more process tools and, therefore, may enable the one or more process tools to maintain overlay within a selected tolerance across multiple exposures on subsequent samples in the same or different batches.

[0077] Figure 10 A process flow diagram illustrating steps of a method 1000 of forming a metrology target 100 according to one or more embodiments of the present disclosure is described.

[0078] At step 1002, a first set of pattern elements 102 compatible with a first metrology mode is formed. For example, pattern elements 106 a through 106 h of the first set of pattern elements 102 can be fabricated by one or more process steps (e.g., but not limited to, one or more deposition, photolithography, or etching steps), wherein the pattern elements 106 a through 106 h of the first set of pattern elements 102 can be formed on different layers of a metrology target 100. The pattern elements 106 a through 106 h can be formed using one or more process tools (e.g., photolithography tools).

[0079] At step 1004, a second set of pattern elements 104 compatible with a second metrology mode is formed. For example, the second set of pattern elements 104 can be fabricated through one or more process steps (such as, but not limited to, one or more deposition, photolithography, or etching steps), wherein the pattern elements 106a-106h of the second set of pattern elements 104 can be formed on different layers of the metrology target 100. It should be noted that step 1004 is not limited to forming the second set of pattern elements 104 sequentially after forming the first set of pattern elements 102, and the second set of pattern elements 104 and the first set of pattern elements 102 can be formed simultaneously.

[0080] In some embodiments, method 1000 may include step 1006, in which a third set of pattern elements 502 compatible with a third measurement mode is formed. For example, the third set of pattern elements 502 may be fabricated through one or more process steps (such as, but not limited to, one or more deposition, photolithography, or etching steps), wherein the third set of pattern elements 502 may be formed on a different layer of the metrology target 100. It should be noted that step 1006 is not limited to forming the third set of pattern elements 502 sequentially after forming the second set of pattern elements 104, and the first set of pattern elements 102, the second set of pattern elements 104, and the third set of pattern elements 502 may be formed simultaneously.

[0081] The subject matter described herein sometimes illustrates different components contained within or connected to other components. It should be understood that such depicted architectures are merely exemplary, and in fact many other architectures that achieve the same functionality can be implemented. Conceptually, any component arrangement used to achieve the same functionality is effectively "associated" so that the desired functionality is achieved. Therefore, any two components combined herein to achieve a particular functionality can be considered to be "associated" with each other so that the desired functionality is achieved, regardless of the architecture or intermediate components. Similarly, any two components so associated can also be considered to be "connected" or "coupled" to each other to achieve the desired functionality, and any two components capable of being so associated can also be considered to be "coupleable" to each other to achieve the desired functionality. Specific examples of coupleable include, but are not limited to, physically matable and / or physically interactive components, and / or wirelessly interactive and / or wirelessly interactive components, and / or logically interactive and / or logically interactive components.

[0082] It is believed that the present disclosure and its many attendant advantages will be understood from the foregoing description, and it will be apparent that various changes can be made in the form, construction, and arrangement of components without departing from the disclosed subject matter or sacrificing all of its substantial advantages. The forms described are illustrative only, and the appended claims are intended to cover and encompass such changes. Furthermore, it should be understood that the present disclosure is defined by the appended claims.

Claims

1. A measurement target, comprising: a first set of pattern elements, wherein the first set of pattern elements is compatible with a first metrology mode of a first metrology subsystem along one or more directions; and a second set of pattern elements, wherein the second set of pattern elements is compatible with a second metrology mode of a second metrology subsystem along the one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements. 2 . The metrology target of claim 1 , wherein at least some of the first set of pattern elements are segmented. 3 . The metrology target of claim 1 , wherein at least some of the second set of pattern elements are segmented. 4 . The metrology target of claim 1 , wherein at least some of the second set of pattern elements are divided into two or more groups of segmented portions. The metrology target of claim 1 , wherein the first metrology mode comprises an optical metrology mode. 6 . The metrology target of claim 1 , wherein the first metrology mode comprises at least one of Advanced Imaging Metrology (AIM) or Triple AIM. 7 . The metrology target of claim 1 , wherein the second metrology mode comprises at least one of an optical metrology mode or a particle beam-based metrology mode.

8. The metrology target of claim 7, wherein the second metrology mode comprises Advanced Imaging Metrology (AIMid) in Die.

9. The metrology target of claim 7, wherein the second metrology mode comprises electron beam metrology.

10. The metrology target of claim 1, further comprising a third set of pattern elements compatible with a third metrology mode of a third metrology subsystem along the one or more directions, wherein the third set of pattern elements surrounds at least a portion of the first set of pattern elements.

11. The metrology target of claim 10, wherein the third metrology mode comprises scatterometry-based overlay SCOL metrology.

12. A system comprising: Two or more metrology subsystems, wherein the two or more metrology subsystems are configured to acquire metrology signals from one or more metrology targets of a sample, wherein each of the two or more metrology subsystems comprises: Illumination source; one or more illumination elements configured to direct an illumination beam from the illumination source onto the sample; one or more detectors; and one or more projection elements configured to collect illumination emitted from the sample and direct the illumination to the one or more detectors; and One or more controllers having one or more processors communicatively coupled to the one or more detectors, wherein the one or more processors are configured to execute a set of program instructions maintained in a memory, wherein the set of program instructions are configured to cause the one or more processors to perform the following steps: receiving one or more signals from a first metrology subsystem operating in a first metrology mode, the one or more signals indicative of one or more signals of the illumination emanating from a first set of pattern elements of the one or more metrology targets of the sample; receiving, from a second metrology subsystem operating in a second metrology mode, one or more signals indicative of one or more signals of illumination emanating from a second set of pattern elements of the one or more metrology targets, wherein the one or more metrology targets of the sample include: the first set of pattern elements, wherein the first set of pattern elements is compatible with the first metrology mode of the first metrology subsystem along one or more directions; and the second set of pattern elements, wherein the second set of pattern elements is compatible with the second metrology mode of the second metrology subsystem along the one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements; determining one or more overlay parameters of the first set of pattern elements based on one or more signals acquired from the first set of pattern elements in the first metrology mode; and One or more overlay parameters of the second set of pattern elements are determined based on one or more signals acquired from the second set of pattern elements in the second metrology mode.

13. The system of claim 12, wherein at least some of the first set of pattern elements are segmented. The system of claim 12 , wherein at least some of the second set of pattern elements are segmented.

15. The system of claim 12, wherein at least some of the second set of pattern elements are divided into two or more groups of segmented portions.

16. The system of claim 12, wherein at least one of the two or more metering subsystems comprises: Optical metrology tools.

17. The system of claim 12, wherein the two or more metrology subsystems comprise: Optical metrology tools; and Particle-based metrology tools.

18. The system of claim 12, wherein the two or more metrology subsystems comprise: Optical metrology tools; particle-based metrology tools; and Overlapping SCOL metrology tool based on scatterometry.

19. The system of claim 16, wherein the first metrology mode comprises an optical metrology mode.

20. The system of claim 16, wherein the first metrology mode comprises at least one of Advanced Imaging Metrology (AIM) or Triple AIM.

21. The system of claim 17, wherein the second metrology mode comprises at least one of an optical metrology mode or a particle beam-based metrology mode.

22. The system of claim 17, wherein the second metrology mode comprises Advanced Imaging Metrology (AIMid) in Die.

23. The system of claim 17, wherein the second metrology mode comprises electron beam metrology.

24. The system of claim 12, wherein the one or more metrology targets further comprise a third set of pattern elements compatible with a third metrology mode of a third metrology subsystem along the one or more directions, wherein the third set of pattern elements surrounds at least a portion of the first set of pattern elements.

25. The system of claim 24, wherein the third metering mode comprises: Overlap SCOL metrology based on scatterometry.

26. The system of claim 25, wherein the one or more controllers are configured to determine one or more overlay parameters for the third set of pattern elements based on one or more signals from the two or more metrology subsystems using the third metrology mode.

27. The system of claim 12, wherein the one or more processors are configured to execute the set of program instructions to cause the one or more processors to provide one or more overlap correctable terms based on the one or more overlap parameters.

28. A method of measuring overlap, comprising: lighting a sample having one or more metrology targets; detecting illumination emitted from a first set of pattern elements of the one or more metrology targets of the sample in a first metrology mode of a first metrology subsystem; detecting illumination emitted from a second set of pattern elements of the one or more metrology targets of the sample in a second metrology mode of a second metrology subsystem; determining one or more overlap parameters of the first set of pattern elements based on the illumination emanating from the first set of pattern elements; and determining one or more overlap parameters of the second set of pattern elements based on the illumination emanating from the second set of pattern elements; The second group of pattern elements includes a first portion of the first group of pattern elements.

29. The method of measuring overlay of claim 28, wherein at least some of the first set of pattern elements are segmented.

30. The method of measuring overlay of claim 28, wherein at least some of the second set of pattern elements are segmented.

31. The method of measuring overlay of claim 28, wherein at least some of the second set of pattern elements are divided into two or more groups of segmented portions.

32. The method of measuring overlay of claim 28, wherein the first metrology mode comprises an optical metrology mode.

33. The method of measuring overlay according to claim 28, wherein the first metrology mode comprises at least one of Advanced Imaging Metrology (AIM) or Triple AIM.

34. The method of measuring overlay according to claim 28, wherein the second metrology mode comprises at least one of an optical metrology mode or a particle beam based metrology mode.

35. The method of measuring overlay according to claim 28, wherein the second metrology mode comprises Advanced Imaging In-Die Metrology (AIMid).

36. The method of measuring overlay of claim 28, wherein the second metrology mode comprises electron beam metrology.

37. The method of measuring overlay of claim 28, further comprising detecting illumination emitted from a third set of pattern elements of the one or more metrology targets of the sample in a third metrology mode of a third metrology subsystem, and determining one or more overlay parameters of the third set of pattern elements of the one or more metrology targets of the sample based on the illumination emitted from the third set of pattern elements.

38. The method of measuring overlay according to claim 37, wherein the third metrology mode comprises: Overlap SCOL metrology based on scatterometry.

39. A method of forming a metrology target, comprising: forming a first set of pattern elements, wherein the first set of pattern elements is compatible with a first metrology mode of a first metrology subsystem along one or more directions; and A second set of pattern elements is formed, wherein the second set of pattern elements is compatible with a second metrology mode of a second metrology subsystem along the one or more directions, wherein the second set of pattern elements includes a first portion of the first set of pattern elements, and wherein the second set of pattern elements is surrounded by a second portion of the first set of pattern elements that is not included in the second set of pattern elements.

40. The method of forming a metrology target of claim 39, wherein at least some of the first set of pattern elements are segmented.

41. The method of forming a metrology target of claim 39, wherein at least some of the second set of pattern elements are segmented.

42. The method of forming a metrology target of claim 39, wherein at least some of the second set of pattern elements are divided into two or more groups of segmented portions.

43. The method of forming a metrology target of claim 39, wherein the first metrology mode comprises an optical measurement mode.

44. The method of forming a metrology target according to claim 39, wherein the first metrology mode comprises at least one of Advanced Imaging Metrology (AIM) or Triple AIM.

45. The method of forming a metrology target of claim 39, wherein the second metrology mode comprises at least one of an optical metrology mode or a particle beam-based metrology mode.

46. The method of forming a metrology target of claim 45, wherein the second metrology mode comprises Advanced Imaging Metrology (AIMid) in Die.

47. The method of forming a metrology target of claim 45, wherein the second metrology mode comprises electron beam metrology.

48. The method of forming a metrology target of claim 39, further comprising forming a third set of pattern elements along the one or more directions that are compatible with a third metrology mode of a third metrology subsystem, wherein the third set of pattern elements surrounds at least a portion of the first set of pattern elements.

49. The method of forming a metrology target of claim 48, wherein the third metrology mode comprises scatterometry-based overlay SCOL metrology.

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