Large scale measurement sampling using multiple chucks and optical columns

Abstract

A measurement system may include two or more sets of optical subsystems to simultaneously produce measurement data regarding two or more samples; a coarse translation stage providing movement along a plane; two or more fine translation stages disposed on the coarse translation stage, arranged in a common mode with the two or more sets of optical subsystems, wherein each of the fine translation stages provides motion along the plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems. The system may further include a controller to independently direct each of the fine translation stages and an associated one of the optical subsystems to generate measurement data for a respective sample, and generate one or more measurements of the sample based on the associated measurement data.

Description

Technical Field

[0001] This disclosure generally relates to optical characterization, and more specifically, to metrological sampling using multiple measurement columns and multiple sample stages. Background Technology

[0002] Optical measurement systems typically consist of a single measurement column and a single sample on a translation stage for positioning. However, the measurement throughput of this configuration is often limited by the translation stage. Furthermore, the workload of providing a translation stage suitable for semiconductor manufacturing, which has relatively fast traverse speeds and low settling times, can be prohibitively expensive and have a limited impact on measurement throughput. Therefore, there is a need to develop systems and methods that address these shortcomings. Summary of the Invention

[0003] A measurement system is disclosed according to one or more illustrative embodiments. In one embodiment, the system includes two or more sets of optical subsystems configured to simultaneously generate measurement data about two or more samples. In one embodiment, the system includes a coarse translation stage that provides movement along a plane. In another embodiment, the system includes two or more fine translation stages disposed on the coarse translation stage in a pattern common to the two or more sets of optical subsystems, wherein each of the two or more fine translation stages provides movement along the plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems. In another embodiment, according to one or more metrics, the two or more fine translation stages provide at least one of a shorter travel distance or improved performance compared to the coarse translation stage. In one embodiment, the system includes a controller to independently guide each of the two or more fine translation stages and an associated one of the two or more sets of optical subsystems to generate measurement data for a corresponding one of the two or more samples, and to generate one or more measurements for each of the two or more samples based on the associated measurement data.

[0004] A motion system is disclosed according to one or more illustrative embodiments. In one embodiment, the system includes two or more sets of optical subsystems configured to simultaneously generate measurement data about two or more samples. In one embodiment, the system includes a coarse translation stage that provides motion along a plane. In another embodiment, the system includes two or more fine translation stages disposed on the coarse translation stage and arranged in a common pattern with the two or more sets of optical subsystems, wherein each of the two or more fine translation stages provides motion along the plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems for measurement according to a formulation. In another embodiment, the two or more fine translation stages provide at least one of a shorter travel distance or improved resolution compared to the coarse translation stage.

[0005] A method is disclosed according to one or more illustrative embodiments. In an embodiment, the method includes positioning two or more samples for parallel measurement via two or more optical subsystems, wherein the two or more samples are positioned on two or more fine translation stages coupled to a common coarse translation stage and arranged in a pattern common to the two or more optical subsystems. In an embodiment, the two or more fine translation stages provide at least one of a shorter travel distance or improved resolution compared to the coarse translation stage. In an embodiment, the method includes independently generating one or more measurements of the two or more samples based on measurement data from the two or more optical subsystems.

[0006] A measurement system is disclosed according to one or more illustrative embodiments. In one embodiment, the system includes two or more sets of optical subsystems for simultaneously generating measurement data about two or more samples. In another embodiment, the system includes two or more translation stages arranged in a common pattern with the two or more sets of optical subsystems, each of the two or more translation stages providing movement along a plane and arranged to position one of the two or more samples below one of the two or more sets of optical subsystems. In another embodiment, the system includes a support structure providing at least mechanical support to the two or more translation stages. In yet another embodiment, the system includes a controller to independently guide each of the two or more fine translation stages and an associated one of the two or more sets of optical subsystems to generate measurement data for a corresponding one of the two or more samples, and to generate one or more measurements for each of the two or more samples based on the associated measurement data.

[0007] It should be understood that the foregoing overview and the following detailed description are merely illustrative and explanatory, and do not necessarily limit the invention as claimed. The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments of the invention and, together with the overview, serve to explain the principles of the invention. Attached Figure Description

[0008] Those skilled in the art can better understand the many advantages of this disclosure by referring to the accompanying drawings.

[0009] Figure 1A This is a block diagram of a measurement system providing parallel optical measurements according to one or more embodiments of the present disclosure.

[0010] Figure 1B This is a simplified schematic diagram of a first configuration of a measurement system according to one or more embodiments of the present disclosure.

[0011] Figure 1C This is a simplified schematic diagram of a second configuration of a measurement system according to one or more embodiments of the present disclosure.

[0012] Figure 1D This is a simplified schematic diagram of an optical subsystem according to one or more embodiments of the present disclosure.

[0013] Figure 2A This is a top view of a measurement system according to one or more embodiments of the present disclosure, the measurement system comprising two columns arranged side by side, each column having a single optical subsystem.

[0014] Figure 2B This is a top view of a measurement system according to one or more embodiments of the present disclosure, the measurement system comprising two columns arranged side by side, each column having four optical subsystems.

[0015] Figure 2C This is a top view of a measurement system according to one or more embodiments of the present disclosure, the measurement system comprising four pillars arranged in a 2D array, each pillar having a single optical subsystem.

[0016] Figure 3 It is a simplified top view of two samples having different layouts of measurement targets that can be simultaneously characterized by a measurement system, according to one or more embodiments of this disclosure.

[0017] Figure 4A This is a top view of a measurement system according to one or more embodiments of the present disclosure, the measurement system including a rotatable platform in a first position.

[0018] Figure 4B This is a top view of a measurement system according to one or more embodiments of the present disclosure, the measurement system including a rotatable platform in a second position.

[0019] Figure 5 This is a flowchart illustrating the steps performed in a method for sample localization according to one or more embodiments of the present disclosure. Detailed Implementation

[0020] The disclosed subject matter will now be described in detail with reference to the accompanying drawings. This disclosure has been particularly shown and described with respect to specific embodiments and their particular features. The embodiments set forth herein should 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 detail can be made without departing from the spirit and scope of this disclosure.

[0021] Embodiments of this disclosure relate to systems and methods for providing parallel optical measurements of samples using multiple sets of measurement columns (e.g., multiple sets of optical subsystems), and a unified sample positioning assembly that provides independent positioning of different samples to enable independent control of the sampling schedule for each sample. For example, multiple sets of measurement columns can provide simultaneous but independent measurements of multiple samples. Furthermore, each set of measurement columns may comprise a single column or multiple columns to provide one or more parallel measurements at different locations of a particular sample.

[0022] The sample positioning assembly may include various components for providing independent positioning of each sample while maintaining a uniform and compact system. In some embodiments, the sample positioning assembly includes multiple independent fine translation stages for independently positioning samples (e.g., mounted on chucks) below each set of measurement columns with relatively high accuracy, wherein the fine translation stages are mounted to a common coarse translation stage in a pattern matching the layout of the column sets. In this manner, the coarse translation stage provides a relatively coarse positioning of all samples relative to the column sets, while the fine translation stages provide independent fine positioning of each sample for measurement. In some embodiments, the measurement system includes independent translation stages for each set of measurement columns and support structures for providing at least mechanical support to the independent translation stages. For example, this support structure may include, but is not limited to, a monolithic granite structure, a platform, or a housing. For example, a common housing may enclose the various translation stages and other components of the columns.

[0023] Furthermore, various measurement columns and sample positioning assemblies can be installed as a single unit or otherwise housed together to provide large-scale sampling of multiple samples in a compact, unified system. Additionally, the various columns can share components, such as, but not limited to, illumination sources and / or detectors, to further promote compactness.

[0024] The systems and methods disclosed herein facilitate parallel measurements of multiple samples as a technique for scaling measurement throughput. For example, measurement throughput can be scaled with the number of columns and associated fine translation stages. Furthermore, different measurement formulations (e.g., target layout, sampling plan, measurement parameters, or the like) can be implemented for each column.

[0025] As used herein, the terms “coarse” and “fine” are used to indicate a relative degree of performance according to at least one metric. For example, a fine translation stage may have a shorter travel distance compared to a process translation stage. As another example, a fine translation stage may have increased performance relative to a coarse translation stage in terms of metrics including, but not limited to, accuracy, resolution, repeatability, translation speed, acceleration (e.g., acceleration and / or deceleration time), or settling time.

[0026] In some embodiments, the precision translation stage further provides independent rotational, flipping, and / or tilting positioning of various samples. Independent rotational positioning can be used, but is not limited to, providing multiple measurements of samples at different rotational positions as a means of reducing or otherwise mitigating tool-induced displacement (TIS) or other errors.

[0027] Focus control can be provided by positioning portions of the sample and / or optical subsystem (e.g., optical components) along a focusing direction outside the measurement plane.

[0028] The measurement systems disclosed herein may include components to facilitate sample loading and / or unloading. In some embodiments, samples may be loaded and / or unloaded independently at locations near associated measurement columns by one or more sample handling systems. In some applications, it may be desirable to translate samples to and from one or more dedicated loading locations. In a general sense, the columns may be distributed in any pattern, such as, but not limited to, one-dimensional (1D) or two-dimensional (2D) arrays. In the case of a 2D distribution, it may be desirable to provide sample loading and / or unloading on a single side. In some embodiments, various fine translation stages are mounted on a rotating stage, which in turn is mounted on the coarse translation stage. In this way, samples can be rotated to one side of the system for loading and / or unloading.

[0029] For reference Figures 1A to 5 The system and method for providing parallel optical measurements are described in more detail according to one or more embodiments of the present disclosure.

[0030] Figure 1A This is a block diagram of a measurement system 100 providing parallel optical measurements according to one or more embodiments of the present disclosure.

[0031] In some embodiments, the measurement system 100 includes two or more measurement columns 102, each containing components for providing independent optical measurements of different samples 104. Each column 102 may include at least one optical subsystem 106, which contains optical components suitable for providing measurement data of the associated sample 104. More generally, any or all columns 102 may include a set of one or more optical subsystems 106. In this way, although Figure 1A A single optical subsystem 106 is depicted for each column 102, but this is only illustrative and not limiting.

[0032] In some embodiments, the measurement system 100 includes a combination of a fine translation stage 108 and a coarse translation stage 110 to provide independent positioning and / or focused positioning of each sample 104 below the corresponding set of optical subsystems 106 (e.g., below the corresponding post 102) (e.g., positioning of each sample 104 and / or any optical subsystem 106 along the focusing direction).

[0033] The measurement system 100 may further include various structures common to all columns 102 to provide a unified system. In some embodiments, the measurement system 100 includes a support structure 112 configured to provide at least mechanical support to various translation stages (e.g., coarse translation stage 110 and fine translation stage 108). For example, the support structure 112 may comprise a monolithic frame formed of any suitable material, such as, but not limited to, stone (e.g., granite or the like) or metal (e.g., aluminum, steel, brass or the like). This frame may provide mechanical support to any translation stage and / or optical subsystem 106. As another example, the support structure 112 may comprise a table or platform that supports components of the measurement system 100 (e.g., but not limited to, optical subsystem 106, various translation stages, or any number of frames).

[0034] Each optical subsystem 106 may include or be configured as any type of optical measurement system. For example, any of the optical subsystems 106 may include or be configured as a metrological tool suitable for providing measurements of various properties of the sample 104, such as but not limited to overlap, characteristic dimensions (e.g., critical dimension (CD)), composition, or thickness. As another example, any of the optical subsystems 106 may be configured as an inspection tool suitable for identifying and / or characterizing defects on the sample 104. Furthermore, the various optical subsystems 106 within the measurement system 100 may be of the same or different types. In this way, the measurement system 100 may be suitable for providing independent parallel characterization of different samples 104 using any combination of techniques.

[0035] Each optical subsystem 106 may implement different formulations for generating measurements. A formulation may include various parameters and / or conditions governing the acquisition of measurements across at least one sample 104. For example, a formulation may include parameters associated with several regions (e.g., targets) of the sample 104 to be characterized, the placement of the targets, and / or the measurement sequence of such targets. Furthermore, in applications where the targets are designed for a measurement purpose (e.g., metrological targets, stacked targets, or the like), the formulation may include aspects of the design of such targets, including, but not limited to, the layout of features on one or more layers. As another example, a formulation may include parameters associated with the configuration of the optical subsystem 106 during measurement. For example, a formulation may include parameters associated with the illumination of the target, such as, but not limited to, wavelength, polarization, power, angle of incidence, spot size, or number of illumination beams. As another example, a formulation may include parameters associated with the collection of light from the target, such as, but not limited to, wavelength, polarization, or collection angle.

[0036] In some embodiments, the optical subsystems 106 of the group are distributed along a measurement plane (e.g., a sample plane). Each group of optical subsystems 106 can be distributed in any 1D or 2D distribution, such as, but not limited to, a 1D or 2D array. Samples 104 can then be positioned in the measurement plane with a common distribution to the optical subsystems 106 of the group, such that each sample 104 is aligned with the corresponding group of optical subsystems 106 for parallel measurements. For example, when the measurement plane is horizontal, the optical subsystems 106 can be positioned above or below the samples 104 during measurement. Orthogonal to the measurement plane (e.g., Figure 1A The Z-direction in the measurement can be characterized as the focusing direction. For example, during measurement, the focused position of sample 104 can be characterized by its absolute position along the measurement direction and / or the relative position of sample 104 with the corresponding optical subsystem 106 (or its components, such as, but not limited to, lenses) along the focusing direction. Furthermore, each set of optical subsystems 106 may comprise any number of optical subsystems 106 arranged in any manner.

[0037] Figures 2A to 2C A non-limiting layout of an optical subsystem 106 according to one or more embodiments of the present disclosure is depicted. Figure 2A This is a top view of a measurement system 100 according to one or more embodiments of the present disclosure, the measurement system 100 comprising two columns 102 arranged side by side (here, along the X direction), each column 102 having a single optical subsystem 106. Figure 2B This is a top view of a measurement system 100 according to one or more embodiments of the present disclosure, the measurement system 100 comprising two columns 102 arranged side-by-side (here, along the X direction), each column 102 having four optical subsystems 106. Therefore, Figure 2BThis illustrates a configuration where different portions of each sample 104 can be independently characterized by different optical subsystems 106. However, it should be noted that any particular column 102 can have any number or distribution of optical subsystems 106, such that... Figure 2B The specific depictions in this document are illustrative only and are not intended to limit this disclosure. Figure 2C This is a top view of a measurement system 100 according to one or more embodiments of the present disclosure, the measurement system 100 comprising four columns 102 arranged in a 2D array, each column 102 having a single optical subsystem 106.

[0038] For overall reference Figures 1A to 1C The components for positioning sample 104 relative to optical subsystem 106 for parallel measurements are now described in more detail according to one or more embodiments of the present disclosure.

[0039] Precise positioning of each sample 104 relative to one or more optical subsystems 106 in the corresponding group is typically required. In a general sense, the measurement system 100 may include any combination of translation stages that provide actuation along any degree of freedom to position components of the sample 104 and / or optical subsystem 106. For example, components of the sample 104 and / or optical subsystem 106 may be coupled to a stage having linear actuators (e.g., 1D and / or two 2D actuators), rotary actuators, tilt / flip actuators, or the like. In this way, components of the sample 104 and / or optical subsystem 106 can be positioned in multiple degrees of freedom, including lateral position in the measurement plane, axial position in the focusing direction, or rotational position in the measurement plane.

[0040] In some embodiments, the measurement system 100 includes a cascaded arrangement of translation stages with different travel distances (e.g., range of motion) and / or performance parameters (e.g., accuracy, resolution, repeatability, translation speed, acceleration (e.g., acceleration and / or deceleration time) or settling time) to position the sample 104 in the measurement plane (e.g., the XY plane) relative to various groups of optical subsystems 106. This cascaded arrangement of coarse translation stage 110 and fine translation stage 108 enables independent control of the sampling mode for each sample 104.

[0041] For example, the measurement system 100 may include two or more fine translation stages 108 (e.g., micro stages), each of which holds one of the samples 104 in place. For example, a sample chuck (not shown) may be mounted to each of the fine translation stages 108 and / or integrated with each of the fine translation stages 108 to hold the sample 104 in place during measurement. The fine translation stages 108 may then be coupled to one or more coarse translation stages 110 (e.g., giant stages) to provide additional positioning capabilities.

[0042] In some embodiments, one or more coarse translation stages 110 provide coarse two-dimensional (2D) positioning of sample 104 in a measurement plane (e.g., the XY plane), while fine translation stages 108 provide independent fine positioning of each sample 104 via at least one of 2D positioning, rotational positioning, or flip / tilt positioning in the measurement plane. It is considered herein that rotational positioning via fine translation stages 108 can enable accurate oriented alignment of features on sample 104 relative to illumination from optical subsystem 106 and / or sequential measurements under rotational symmetry conditions to mitigate TIS or other errors.

[0043] As previously described herein, the fine translation stage 108 may have a smaller travel distance (e.g., range of motion) and / or better performance parameters (e.g., accuracy, resolution, repeatability, translation speed, acceleration (e.g., acceleration and / or deceleration time) or settling time) relative to the coarse translation stage 110. This cascaded configuration of the fine translation stage 108 and the coarse translation stage 110 can provide numerous benefits for the efficient positioning of sample 104. As considered herein, translation stages can implement various trade-offs between load capacity, weight, size, travel distance, travel speed, acceleration (e.g., acceleration and / or deceleration time), accuracy, repeatability, cost, or the like. For example, providing a large travel distance with high travel speed, rapid acceleration, high accuracy, and high repeatability can require significant cost. However, the cascaded arrangement of the fine translation stage 108 and the coarse translation stage 110 can provide an efficient solution through multiple stages with different performance trade-offs.

[0044] For example, the travel distance of the fine translation stage 108 can be approximately equal to or less than the size of the sample 104 in the relevant direction. For example, in the case of a 300 mm semiconductor wafer, the fine translation stage 108 can have a travel distance of 300 mm or less in the measurement plane (e.g., + / - 150 mm from the center position). In this configuration, the coarse translation stage 110 can provide coarse alignment and / or positioning of all samples 104 relative to the optical subsystem 106 for loading / unloading, while the fine translation stage 108 can provide fine alignment for each sample 104 according to the corresponding sampling plan.

[0045] Either the fine translation stage 108 and / or the coarse translation stage 110 can be any type of stage known in the art, such as, but not limited to, an air bearing stage, a mechanical bearing stage, or a magnetic levitation stage. Furthermore, either the fine translation stage 108 and / or the coarse translation stage 110 can have any suitable design. For example, Figures 2A to 2CThe fine translation stage 108 is depicted as coupled to a first directional linear track 202 that provides motion along a first direction (e.g., the X direction), wherein the first directional linear track 202 is coupled to a second directional linear track 204 that provides motion along an orthogonal direction (e.g., the Y direction). Furthermore, the fine translation stage 108 is depicted as providing both independent 2D positioning and rotational positioning of each sample 104 in the measurement plane.

[0046] Figure 1B and 1C Different configurations of the measurement system 100 with different arrangements of translation stage are described.

[0047] Figure 1B This is a simplified schematic diagram of a first configuration of a measurement system 100 according to one or more embodiments of the present disclosure. Figure 1B In this configuration, the fine translation stage 108 is coupled to or integrated with a single coarse translation stage 110 (e.g., a giant stage). In this configuration, the coarse translation stage 110 can position all samples 104 near the respective optical subsystems 106 and / or move samples 104 to and from the loading area, while the fine translation stage 108 provides precise, independent control over each sample 104. As considered herein, Figure 1B The configuration described herein enables parallel measurement of multiple samples 104 with independent sample control within a compact, unified measurement system 100.

[0048] Figure 1C This is a simplified schematic diagram of a second configuration of a measurement system 100 according to one or more embodiments of the present disclosure. Figure 1C In the measurement system 100, each column 102 includes a fine translation stage 108 and a coarse translation stage 110. This configuration can similarly provide parallel measurements of multiple samples 104 with independent sample control within a compact, uniform measurement system 100, but can utilize trade-offs between different groups. For example, Figure 1C The configuration depicted in the text can utilize a relatively small, coarse translation stage 110, rather than as... Figure 1B The single, larger coarse translation stage 110 depicted in the figure reduces the weight requirement of each coarse translation stage 110.

[0049] In addition, such as Figure 1CAs depicted, translation stages for some or all of the columns 102 may be mounted to or otherwise supported by a common support structure 112, such as, but not limited to, a frame, stage, or housing. For example, the housing may enclose the optical subsystem 106 and various translation stages (e.g., fine translation stage 108 and / or coarse translation stage 110). The various columns 102 may also share additional components, such as, but not limited to, a thermal management system or an environmental system. Furthermore, as described in more detail throughout, the optical subsystems 106 within the same or different columns 102 may share common components, such as, but not limited to, illumination sources, detectors, controllers, or the like. In this manner, this configuration offers advantages over alternatives that include multiple independent measurement systems.

[0050] The control of the working distance between the sample 104 and the optical subsystem 106 is now described in more detail according to one or more embodiments of the present disclosure. In some embodiments, any of the fine translation stages 108 can provide at least 3D positioning (e.g., along the X, Y, and Z directions). In this configuration, the fine translation stages 108 can adjust the position of the sample 104 relative to one or more optical subsystems 106 in a particular post 102. In some embodiments, any of the posts 102 may include one or more translation stages configured to adjust the position of the optical subsystem 106 (or a portion thereof, such as an optical head, one or more lenses, or the like) relative to the sample 104. For illustrative purposes, such translation stages may be referred to herein as focusing translation stages. This configuration provides independent control of the working distance of each optical subsystem 106 along the focusing direction and is therefore particularly advantageous, but not limited to, configurations in which the posts 102 have multiple optical subsystems 106.

[0051] Furthermore, column 102 may include any number or type of focusing translation stages for adjusting the position of optical subsystem 106 along the focusing direction (e.g., the Z direction here). For example, Figure 1B and 1C The illustration depicts a non-limiting configuration in which each post 102 includes a fine translation stage 108 (e.g., a fine focusing translation stage) and a coarse translation stage 110 (e.g., a coarse focusing translation stage) to position the optical subsystem 106 along the focusing direction. However, this is merely illustrative. In some embodiments, post 102 may include a single translation stage to adjust the focusing position of the optical subsystem 106 (or a portion thereof).

[0052] For reference Figure 3 In view of this paper, the system and method disclosed herein enable parallel measurement of multiple samples 104 and / or multiple locations on each sample 104 using an independent and controllable sampling plan. Figure 3This is a simplified top view of two samples 104-1, 104-2 with different layouts of a measurement target 302 that can be simultaneously characterized by the measurement system 100, according to one or more embodiments of this disclosure. Specifically, samples 104-1, 104-2 are positioned on independent fine translation stages 108-1, 108-2. Furthermore, Figure 3 A portion of the coarse translation stage 110 (e.g., a first-direction linear track 202) is shown in the image.

[0053] Figure 3 Different layouts of the target 302 for measurement within sample region 304 are also described (e.g., based on different sampling plans in different formulations). The systems and methods disclosed herein can provide parallel measurements of two samples 104-1 and 104-2.

[0054] For example, if the travel distance of the fine translation stages 108-1 and 108-2 is equal to the sample size, then the coarse translation stage 110 can position each sample 104-1 and 104-2 at its center relative to the corresponding optical subsystem 106. For instance, the coarse translation stage 110 can position the center point of each sample 104-1 and 104-2 within the measurement field of view of the corresponding optical subsystem 106. Therefore, the fine translation stages 108-1 and 108-2 can be used to perform measurements at any desired location on the samples 104-1 and 104-2 through independent control.

[0055] To give another example, if the travel distance of the fine translation stages 108-1 and 108-2 is shorter than the sample size, then the coarse translation stage 110 can provide a coarse alignment of all samples 104-1 and 104-2 to the corresponding sample area 304, so that the fine translation stage 108 can independently control the position of samples 104-1 and 104-2 within the corresponding sample area 304.

[0056] In either case, parallel measurements of samples 104-1 and 104-2 are achieved through the independent positioning of fine translation stages 108-1 and 108-2, thus increasing measurement throughput compared to alternative techniques.

[0057] It should be noted that Figure 3 This is illustrative only and should not be construed as restrictive. For example, Figure 3 Not provided to scale. Furthermore, sample 104 may contain any number or arrangement of targets 302.

[0058] Again, refer to the overall Figures 1A to 3In view of this document, the systems and methods disclosed herein can support a wide range of sampling modes and configurations. For example, the systems and methods disclosed herein can implement any combination of measurements based on motion and measurement (MAM) technology or scanning technology for any of the targets 302 on or on the sample 104.

[0059] For reference Figure 4A and 4B The loading and unloading of sample 104 will be described in more detail according to one or more embodiments of this disclosure. Figure 4A This is a top view of a measurement system 100 according to one or more embodiments of the present disclosure, the measurement system 100 including a rotatable platform 402 in a first position. Figure 4B This is a top view of a measurement system 100 according to one or more embodiments of the present disclosure, the measurement system 100 including a rotatable platform 402 in a second position.

[0060] In a general sense, measurement system 100 is compatible with any type of sample handling system 404 in the relevant field. Figure 4A and 4B In the illustration, the sample handling system 404 is depicted as having two sample handling arms 406 for loading and / or unloading the sample 104, but this is only illustrative and not limiting.

[0061] In some embodiments, the sample handling system 404 may have direct access to each of the fine translation stages 108 (e.g., a sample chuck on or integrated into the fine translation stage 108). In this manner, the sample handling system 404 can directly load and / or unload samples 104 onto the respective fine translation stage 108.

[0062] However, in some applications, it is desirable to facilitate loading and / or unloading at dedicated locations (e.g., but not limited to, a dedicated side or portion of the measuring system 100). In this case, it is desirable to efficiently position various precision translation stages 108 at the dedicated locations.

[0063] In some embodiments, the measurement system 100 includes a rotary stage (not shown) coupled to and / or integrated with the coarse translation stage 110 to rotate a fine translation stage 108. For example, at least some of the fine translation stages 108 may be mounted to and / or integrated with platform 402, which may be rotated by the rotary stage.

[0064] like Figures 4A to 4BAs described, multiple fine translation stages 108 can be mounted to platform 402, which can be rotated (e.g., via a rotary stage not shown) to any desired angular orientation. In this way, each of the fine translation stages 108 can be rotated to a position accessible on a selected side of the measurement system 100 for loading and / or unloading the sample 104.

[0065] Specifically, Figure 4A The first orientation of platform 402 is depicted, wherein fine translation stages 108-3, 108-4 are positioned along a selected side 408 of measurement system 100 to couple with sample handling arm 406 for loading and / or unloading sample 104. Figure 4B Describe the second orientation of platform 402 as it rotates between. Figures 4A to 4B The configuration in which the coarse translation stage 110 has positioned the fine translation stage 108 near the side 408 is further described.

[0066] However, it should be understood that Figures 4A to 4B This is for illustrative purposes only and is not limiting. For example, the measurement system 100 may include any number of rotatable platforms 402, each of which is fixed with any number of fine translation stages 108 in any distribution.

[0067] For reference Figures 1A to 1D Various aspects of the optical subsystem 106 are described in more detail according to one or more embodiments of the present disclosure.

[0068] In some embodiments, the measurement system 100 includes a controller 114. In some embodiments, the controller 114 includes one or more processors 116 configured to execute program instructions maintained in a memory 118 (e.g., a memory device). The controller 114 may be communicatively coupled to any component of the measurement system 100 to provide unidirectional and / or bidirectional communication. In this manner, the controller 114 may (e.g., via one or more processors 116) execute program instructions, causing the processors 116 to perform any of the various process steps described throughout this disclosure, such as, but not limited to (e.g., via control signals to the fine translation stage 108 and the coarse translation stage 110) positioning the sample 104 for measurement by the optical subsystem 106, receiving measurement data associated with the sample 104 from the optical subsystem 106, or generating a measurement of the sample 104 based on the measurement data.

[0069] One or more processors 116 of controller 114 may comprise any processing element known in the art. In this sense, one or more processors 116 may comprise any microprocessor-type device configured to execute algorithms and / or instructions. In some embodiments, one or more processors 116 may comprise a desktop computer, host computer system, workstation, image computer, parallel processor, or any other computer system (e.g., a networked computer) configured to execute a program configured to operate measurement system 100, as described throughout this disclosure. It should be further appreciated that the term “processor” may be broadly defined to encompass any device having one or more processing elements that execute program instructions from non-transitory memory 118. Furthermore, the steps described throughout this disclosure may be performed by a single controller 114 or alternatively by multiple controllers. Additionally, controller 114 may comprise one or more controllers housed in a common housing or multiple housings. In this manner, any controller or combination of controllers may be separately packaged as modules suitable for integration into measurement system 100.

[0070] Memory 118 may comprise any storage medium known in the art suitable for storing program instructions executable by one or more associated processors 116. For example, memory 118 may comprise a non-transitory memory medium. As another example, memory 118 may comprise, but is not limited to, read-only memory, random access memory, magnetic or optical storage devices (e.g., magnetic disks), magnetic tape, solid-state drives, and the like. It should be further noted that memory 118 may be housed in a common controller housing with one or more processors 116. In some embodiments, memory 118 may be remotely located relative to the physical location of one or more processors 116 and controller 114. For example, one or more processors 116 of controller 114 may access remote memory (e.g., a server) accessible via a network (e.g., the Internet, an intranet, and the like). Therefore, the above description should not be construed as limiting the invention but is merely illustrative.

[0071] As previously described, the measurement system 100 may include any number or type of optical subsystems 106.

[0072] Figure 1D This is a simplified schematic diagram of an optical subsystem 106 according to one or more embodiments of the present disclosure.

[0073] In some embodiments, the optical subsystem 106 includes an illumination subsystem 120 for generating illumination 122 in the form of one or more illumination beams to illuminate the sample, and a collection subsystem 124 for collecting light (e.g., sample light 126) from the illuminated sample 104.

[0074] In some embodiments, the illumination subsystem 120 includes an illumination source 128 configured to generate illumination 122 in the form of at least one illumination beam. Illumination from the illumination source 128 may include light of one or more selected wavelengths, including, but not limited to, ultraviolet (UV) radiation, visible radiation, or infrared (IR) radiation. The illumination source 128 may include any type of illumination source suitable for providing at least one illumination beam. In some embodiments, the illumination source 128 is a laser source. For example, the illumination source 128 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 respect, the illumination source 128 may provide an illumination beam with high coherence (e.g., high spatial coherence and / or temporal coherence). In some embodiments, the illumination source 128 includes a laser sustained plasma (LSP) source. For example, the illumination source 128 may include, but is not limited to, an LSP lamp, LSP bulb, or LSP cavity suitable for housing one or more elements capable of emitting broadband illumination when excited into a plasma state by a laser source.

[0075] In some embodiments, the illumination subsystem 120 includes one or more optical components adapted to modify and / or adjust one or more illumination beams and to guide one or more illumination beams to the sample 104. For example, the illumination subsystem 120 may include one or more illumination lenses 130. In some embodiments, the illumination subsystem 120 includes one or more illumination control optics 132 to shape or otherwise control one or more illumination beams. For example, the illumination control optics 132 may include, but are not limited to, one or more field stops, one or more pupil stops, 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, one or more beam shapers, or one or more mirrors (e.g., static mirrors, translation mirrors, scanning mirrors, or the like).

[0076] In some embodiments, the optical subsystem 106 includes an objective lens 134 to focus one or more illumination beams onto a sample 104 (e.g., a stacked target having stacked target elements positioned on two or more layers of the sample 104).

[0077] In some embodiments, one or more illumination beams may be angularly constrained on sample 104, such that periodic structures in sample 104 can produce discrete diffraction orders. Furthermore, one or more illumination beams may be spatially constrained, such that they illuminate selected portions of sample 104.

[0078] In some embodiments, the collection subsystem 124 includes one or more detectors 136, wherein any detector 136 can be positioned at any suitable location. For example, the detector 136 can be positioned at a field plane conjugate to the sample 104 or the pupil plane (e.g., a diffraction plane, a Fourier plane, or the like). In this way, the optical subsystem 106 can be adapted for any type of measurement. The optical subsystem 106 can include any number or type of detectors 136. In some embodiments, the optical subsystem 106 includes a multi-pixel sensor, such as, but not limited to, a complementary metal-oxide-semiconductor (CMOS) device, a charge-coupled device (CCD), a photodiode array, a line sensor, or a time-delay integration (TDI) sensor. In some embodiments, the optical subsystem 106 includes one or more single-pixel sensors, such as, but not limited to, a photodiode or an avalanche photodiode. Furthermore, one or more detectors 136 in the optical subsystem 106 can be configured to provide measurements when the sample 104 is stationary (e.g., MAM technology) or when the sample 104 is in motion (e.g., scanning technology).

[0079] The collection subsystem 124 may include one or more optical elements suitable for modifying and / or adjusting the sample light 126. In some embodiments, the collection subsystem 124 includes one or more collection lenses 138 (e.g., to collimate the sample light 126, a relay pupil, and / or a field plane or the like), which may include, but do not necessarily include, an objective lens 134. In some embodiments, the collection subsystem 124 includes one or more collection control optics 140 to shape or otherwise control the sample light 126. For example, the collection control optics 140 may include, but are not limited to, one or more field stops, one or more pupil stops, 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, one or more beam shapers, or one or more mirrors (e.g., static mirrors, translation mirrors, scanning mirrors, or the like).

[0080] The components within the optical subsystem 106 can be arranged relative to the sample 104 in any suitable manner. For example, the optical subsystem 106 may include one or more components (e.g., one or more lenses or the like) aligned with the sample 104 in the measurement plane (e.g., positioned above the sample 104) during measurement. However, not all components need to be aligned with the sample 104. For example, the optical subsystem 106 may include an optical head configured to be physically positioned near the sample 104 and additional components that can be positioned more flexibly in convenient locations. For example, the optical head may include components (objective lens 134 and any number of additional components) configured to illuminate the sample 104 and / or collect light from the sample 104 during measurement.

[0081] Furthermore, different optical subsystems 106 within the same or different columns 102 may share one or more components. For example, two or more optical subsystems 106 may share a common illumination source 128 and / or a portion of the illumination subsystem 120. As another example, two or more optical subsystems 106 may share a common detector 136 and / or a portion of the collection subsystem 124. For example, Figure 1D A beam splitter 142 is depicted, configured to allow the objective lens 134 to direct illumination 122 to the sample 104 and collect sample light 126.

[0082] For reference Figure 5 , Figure 5 This is a flowchart illustrating the steps performed in a method 500 for sample localization according to one or more embodiments of the present disclosure. In the context of the measurement system 100, the embodiments and implementation techniques previously described herein should be interpreted as extending to method 500. For example, various components of the measurement system 100 may be configured to implement various steps of method 500. However, it should be further noted that method 500 is not limited to the architecture of the measurement system 100.

[0083] In some embodiments, method 500 includes step 502 of positioning two or more samples 104 for parallel measurements via two or more optical subsystems 106, wherein the two or more samples are positioned on two or more fine translation stages 108, the fine translation stages 108 being coupled to one or more coarse translation stages 110 and arranged in a common pattern with the two or more optical subsystems 106. For example, the two or more fine translation stages 108 may provide at least one of a shorter travel distance compared to the coarse translation stages 110 or improved resolution compared to the one or more coarse translation stages 110.

[0084] In some embodiments, method 500 includes step 504 of independently generating one or more measurements of two or more samples 104 based on measurement data from two or more optical subsystems 106.

[0085] Focus control in implementation method 500 can be provided by a translation stage configured to adjust the position of at least a portion of the optical subsystem 106 in the focusing direction and / or the position of the sample 104 along the focusing direction.

[0086] The topics described herein sometimes illustrate different components housed within or connected to other components. It should be understood that such depicted architectures are merely illustrative, and many other architectures can in fact be implemented to achieve the same functionality. Conceptually, any arrangement of components achieving the same functionality is effectively “associated” to achieve the desired functionality. Therefore, without considering architecture or intermediate components, any two components combined in this document to achieve a particular functionality can be considered “associated” with each other to achieve the desired functionality. Similarly, any two such associated components can also be considered “connected” or “coupled” to each other to achieve the desired functionality, and any two components that can be suchly associated can also be considered “coupleable” to each other to achieve the desired functionality. Specific instances of coupling include, but are not limited to, physically interactive and / or wirelessly interactive components and / or logically interactive components.

[0087] It is believed that this disclosure and its many accompanying advantages will be understood from the foregoing description, and it will be appreciated that various changes can be made to the form, construction, and arrangement of the components without departing from the disclosed subject matter or sacrificing all its significant advantages. The forms described are merely illustrative, and the appended claims are intended to cover and encompass such changes. Furthermore, it should be understood that the invention is defined by the appended claims.

Claims

1. A measurement system comprising: Two or more sets of optical subsystems configured to simultaneously generate measurement data about two or more samples; A coarse translation stage, configured to provide movement along a plane; Two or more fine translation stages are mounted on the coarse translation stage in a pattern common to the two or more sets of optical subsystems, wherein each of the two or more fine translation stages provides movement along the plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems, wherein the two or more fine translation stages provide at least one of a shorter travel distance or improved performance compared to the coarse translation stage according to one or more metrics; and A controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: Independently guide each of the two or more precision translation stages and one of the associated sets of two or more optical subsystems to generate measurement data for the corresponding one of the two or more samples; and One or more measurements are generated for each of the two or more samples based on the associated measurement data.

2. The measurement system according to claim 1, further comprising: Two or more focusing translation stages configured to provide linear movement along a focusing direction orthogonal to the plane, wherein each of the two or more focusing translation stages is configured to position at least a portion of one of the two or more sets of optical subsystems along the focusing direction.

3. The measurement system of claim 2, wherein the two or more focusing translation stages comprise: Fine focusing translation stage and coarse focusing translation stage, used for each of the two or more sets of optical subsystems.

4. The measurement system of claim 1, wherein the two or more fine translation stages further provide linear motion of the two or more samples along a focusing direction orthogonal to the plane.

5. The measurement system of claim 1, wherein the two or more samples have different sampling plans, wherein independently guiding each of the two or more fine translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data for the corresponding one of the two or more samples comprises: Independently guide each of the two or more fine translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data of the corresponding one of the two or more samples based on the corresponding one in the sampling plan.

6. The measurement system of claim 1, wherein the two or more samples have a common sampling plan, wherein independently guiding each of the two or more fine translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data for the corresponding one of the two or more samples comprises: Independently guide each of the two or more fine translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data of the corresponding one of the two or more samples based on the common sampling plan.

7. The measurement system of claim 1, wherein the two or more fine translation stages further provide rotational motion in the plane.

8. The measurement system of claim 1, wherein the two or more fine translation stages are mounted on a platform, wherein the platform is rotatable by at least one of the coarse translation stage or a rotary stage mounted between the coarse translation stage and the platform.

9. The measurement system of claim 1, wherein the two or more fine translation stages have a travel distance equal to or less than the size of the corresponding two or more samples, wherein the coarse translation stage provides a travel distance greater than the travel distance of the two or more fine translation stages.

10. The measurement system of claim 1, wherein the one or more measurements include: At least one of the measurement or inspection measurements.

11. The measurement system of claim 1, wherein the one or more measurements include: Accuracy, resolution, repeatability, translational velocity, acceleration, or settling time, or at least one of these.

12. The measurement system of claim 1, wherein at least two of the two or more optical subsystems share a common illumination source for illuminating the respective samples.

13. A motion system comprising: A coarse translation stage, configured to provide movement along a plane; and Two or more fine translation stages are mounted on the coarse translation stage and arranged in a manner common to two or more sets of optical subsystems, wherein each of the two or more fine translation stages provides movement along the plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems for measurement according to a formulation, wherein the two or more fine translation stages provide at least one of a shorter travel distance or improved resolution compared to the coarse translation stage, according to one or more metrics.

14. The motion system according to claim 13, further comprising: Two or more focusing translation stages configured to provide linear movement along a focusing direction orthogonal to the plane, wherein each of the two or more focusing translation stages is configured to position at least a portion of one of the two or more sets of optical subsystems along the focusing direction.

15. The motion system of claim 14, wherein the two or more focusing translation stages comprise: Fine focusing translation stage and coarse focusing translation stage, used for each of the two or more sets of optical subsystems.

16. The motion system of claim 13, wherein the two or more fine translation stages further provide linear motion of the two or more samples along a focusing direction orthogonal to the plane.

17. The motion system of claim 13, wherein the two or more samples have different sampling plans, wherein the coarse translation stage and the two or more fine translation stages are configured to be independently guided to generate measurement data about the two or more samples based on the respective sampling plans.

18. The motion system of claim 13, wherein the two or more samples have a common sampling plan, wherein the coarse translation stage and the two or more fine translation stages are configured to be simultaneously guided to generate measurement data about the two or more samples based on the common sampling plan.

19. The motion system of claim 13, wherein the two or more precision translation stages further provide rotational motion in the plane.

20. The motion system of claim 13, wherein the two or more fine translation stages are mounted on a platform, wherein the platform is rotatable by at least one of the coarse translation stage or a rotary stage disposed between the coarse translation stage and the platform.

21. The motion system of claim 13, wherein the two or more fine translation stages have a travel distance equal to or less than the size of the corresponding two or more samples, wherein the coarse translation stage provides a travel distance greater than the travel distance of the two or more fine translation stages.

22. The motion system of claim 13, wherein the one or more measures include: Accuracy, resolution, repeatability, translational velocity, acceleration, or settling time, or at least one of these.

23. A method comprising: Positioning two or more samples for parallel measurement via two or more optical subsystems, wherein the two or more samples are mounted on two or more fine translation stages, the two or more fine translation stages being coupled to a common coarse translation stage and arranged in a mode common to the two or more optical subsystems, wherein the two or more fine translation stages provide at least one of a shorter travel distance or improved resolution compared to the coarse translation stage; and One or more measurements of the two or more samples are generated independently based on measurement data from the two or more optical subsystems.

24. A measurement system comprising: Two or more sets of optical subsystems configured to simultaneously generate measurement data about two or more samples; Two or more translation stages are arranged in a pattern common to the two or more sets of optical subsystems, wherein each of the two or more translation stages provides movement along a plane and is arranged to position one of the two or more samples below one of the two or more sets of optical subsystems. A support structure configured to provide at least mechanical support to the two or more translation platforms; and A controller comprising one or more processors configured to execute program instructions that cause the one or more processors to: Independently guide each of the two or more translation stages and one of the associated optical subsystems to generate measurement data for the corresponding one of the two or more samples; and One or more measurements are generated for each of the two or more samples based on the associated measurement data.

25. The measurement system of claim 24, wherein the support structure comprises: Monolithic frame.

26. The measuring system of claim 25, wherein the frame is formed of at least one of granite, steel, aluminum or brass.

27. The measurement system of claim 24, wherein the two are more translation stages mounted on two or more frames, wherein the support structure comprises: A platform that supports the two or more frameworks.

28. The measurement system of claim 24, wherein the support structure comprises: The housing encloses the two or more translation stages and the two or more sets of optical subsystems.

29. The measurement system of claim 24, wherein the support structure further provides thermal management for the two or more translation stages.

30. The measurement system of claim 24, wherein the two or more translation stages comprise: Two or more coarse translation stages; and Two or more fine translation stages, wherein each of the two or more fine translation stages is mounted to one of the two or more coarse translation stages.

31. The measurement system of claim 24, wherein the two or more samples have different sampling schemes, wherein independently guiding each of the two or more translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data for the corresponding one of the two or more samples comprises: Independently guide each of the two or more translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data of the corresponding one of the two or more samples based on the corresponding one in the sampling plan.

32. The measurement system of claim 24, wherein the two or more samples have a common sampling plan, wherein independently guiding each of the two or more translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data for the corresponding one of the two or more samples comprises: Independently guide each of the two or more translation stages and the associated one of the two or more sets of optical subsystems to generate measurement data of the corresponding one of the two or more samples based on the common sampling plan.

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