Method and apparatus for judging light spot condition based on goodness of fit (GOF)

Abstract

Embodiments of the present disclosure relate to a method and apparatus for judging a light spot condition based on goodness of fit (GOF). The method includes: projecting a light spot to be measured to a plurality of predetermined point positions in a predetermined size standard film measurement area, the predetermined size being larger than the size of the light spot to be measured, the standard film measurement area being surrounded by a peripheral film area and having a known thickness, the film thickness of the peripheral film area being significantly different from the film thickness in the standard film measurement area; measuring light reflected from each of the plurality of predetermined point positions to obtain a film thickness measurement spectrum related to each predetermined point position; determining a film thickness spectrum goodness of fit corresponding to each predetermined point position based on the film thickness measurement spectrum obtained for each predetermined point position; and determining at least one of a shape, a size, an energy distribution, and a center of the light spot to be measured based on a plurality of film thickness spectrum goodness of fits originating from the plurality of predetermined point positions.

Description

Technical Field

[0001] The embodiments disclosed herein relate to the field of optical measurement, and particularly to methods and apparatus for determining the condition of a measurement spot used in the field of optical measurement. Background Technology

[0002] In semiconductor manufacturing processes, film thickness measurement equipment such as fully automated high-precision ellipsometers is required to measure film thickness and linewidth. The morphology, energy distribution, and size of the incident light spot on the sample measurement area directly affect the spectral information of the reflected light, thus affecting the accuracy of the measurement results. Therefore, the spot condition, such as spot size measurement and spot morphology distribution, is of great significance in thin film measurement applications. Figure 1 The structural principle diagram of an ellipsometer, a typical film thickness measurement device, is shown.

[0003] In measurement equipment applications, the spot size is usually calculated by defining the spot boundary through the change in energy intensity as the spot transitions from one thin film sample to the surface of another, thereby calculating the spot size. Figure 2 A schematic diagram illustrating the principle of conventional measurement spot morphology is shown. For example... Figure 2 As shown, the straight edge of the pattern on the silicon wafer serves as the boundary, with two different thin film materials on both sides. The thin films on both sides have different reflectivities. When the light spot is completely on one side, the light intensity received by the spectrometer remains basically constant when the silicon wafer is moved along the long axis of the light spot. However, when the light spot passes through the thin film boundary until it is completely on the other side, the light intensity changes continuously. By differentiating this set of light intensity data and performing Gaussian fitting, and defining a standard for judging the boundary of the light spot (such as 3σ or 0.5%) for the Gaussian fitting curve, the center and size of the light spot can be obtained. Figure 3 The Gaussian energy distribution plot commonly used to measure spot morphology is shown. However, when the spot condition is abnormal (e.g., there is tailing or other noise), the spot size calculated by this method may not have direct reference value in engineering applications, leading to deviations in the final measurement results in engineering applications. Summary of the Invention

[0004] The purpose of this disclosure is to propose a novel method for judging the condition of light spots based on goodness of fit (GOF), which can more accurately assess the condition of light spots.

[0005] According to a first aspect of this disclosure, a method for determining the condition of a light spot based on goodness-of-fit (GOF) is provided. The method includes: projecting a light spot to be tested sequentially onto a plurality of predetermined points within a standard thin film measurement region of a predetermined size, the predetermined size being larger than the size of the light spot to be tested; the standard thin film measurement region being surrounded by a peripheral thin film region of known thickness, the thickness of the peripheral thin film region being significantly different from the thickness of the film within the standard thin film measurement region; measuring the light reflected from each of the plurality of predetermined points to obtain a film thickness measurement spectrum associated with each predetermined point; determining a film thickness spectral goodness-of-fit corresponding to each predetermined point based on the film thickness measurement spectrum obtained at each predetermined point; and determining at least one of the morphology, size, energy distribution, and center of the light spot to be tested based on the plurality of film thickness spectral goodness-of-fit values ​​derived from the plurality of predetermined points.

[0006] It will be understood that the GOF-based method of this disclosure can more intuitively reflect the spot condition, such as the regional distribution, size, and center of the spot that affect the measurement results. Furthermore, the method of this disclosure can advantageously combine the spot size with the final measurement results, thereby more accurately guiding the quality assessment of the measurement system during the production process.

[0007] In some embodiments, the plurality of predetermined points form a dot matrix within the standard thin film measurement area at predetermined intervals.

[0008] In some embodiments, the dot matrix is ​​distributed throughout the entire standard thin film measurement area.

[0009] In some embodiments, the plurality of predetermined points are distributed in a ring along the inner boundary of the standard thin film measurement area.

[0010] In some embodiments, the density of the plurality of predetermined points in the middle region of the standard thin film measurement area is less than the density in the region near the boundary of the standard thin film measurement area.

[0011] In some embodiments, the predetermined interval is in the range of 1 μm to 10 μm.

[0012] In some embodiments, determining at least one of the morphology, size, energy distribution, and center of the light spot under test based on multiple goodness-of-fit values ​​derived from the plurality of predetermined points includes: determining a threshold for the film thickness spectral goodness-of-fit; and determining at least one of the morphology, size, energy distribution, and center of the light spot under test based on the film thickness spectral goodness-of-fit values ​​of the plurality of predetermined points that are greater than the threshold.

[0013] In some embodiments, the threshold is in the range of 0.8 to 0.98.

[0014] In some embodiments, projecting the light spot to be tested sequentially onto multiple predetermined points within a standard thin film measurement area of ​​a predetermined size includes: projecting the light spot to be tested sequentially onto multiple different predetermined points within the standard thin film measurement area by translating the standard thin film measurement area relative to the light spot to be tested.

[0015] In some embodiments, the standard thin film measurement area is a rectangular area.

[0016] According to a second aspect of this disclosure, a detection device for determining the condition of a light spot based on goodness-of-fit (GOF) is provided. The detection device includes: a measuring device adapted to measure light reflected from each of the plurality of predetermined points when a light spot to be tested is sequentially projected onto a plurality of predetermined points within a standard thin film measurement area, to obtain a film thickness measurement spectrum associated with each predetermined point; and a processing device configured to operate to perform the method according to any one of the first aspects of this disclosure.

[0017] According to a third aspect of this disclosure, a non-transitory machine-readable storage medium is provided, having stored thereon machine-readable program instructions configured to enable the method according to any one of the first aspects to be executed.

[0018] It should also be understood that the description in the Summary of the Invention is not intended to limit the key or essential features of the embodiments of this disclosure, nor is it intended to restrict the scope of this disclosure. Other features of the embodiments of this disclosure will become readily apparent from the following description. Attached Figure Description

[0019] The above and other features, advantages, and aspects of the embodiments of this disclosure will become more apparent from the accompanying drawings and the following detailed description. In the drawings, the same or similar reference numerals denote the same or similar elements, wherein:

[0020] Figure 1 A schematic diagram of the ellipsometer, a typical film thickness measurement device, is shown.

[0021] Figure 2 A schematic diagram illustrating the principle of conventional measurement spot morphology is shown;

[0022] Figure 3 The Gaussian energy distribution diagram of a conventional measurement spot morphology is shown;

[0023] Figure 4 A schematic diagram of a thin film structure having a standard film thickness measurement region is shown according to an example embodiment of the present disclosure;

[0024] Figure 5A schematic diagram illustrating the operation of determining spot conditions based on film thickness spectral fit goodness of fit according to an example embodiment of the present disclosure is shown.

[0025] Figure 6 It shows the basis Figure 5 The obtained one-dimensional distribution of the film thickness spectral fitting goodness;

[0026] Figure 7 A two-dimensional distribution of the film thickness spectral fit goodness obtained for a test spot according to an example embodiment of the present disclosure is shown;

[0027] Figure 8 A flowchart illustrating a method for determining spot conditions based on a goodness-of-fit (GOF) distribution according to an example embodiment of this disclosure is shown; and

[0028] Figure 9 A functional schematic diagram of a processing apparatus suitable for implementing the methods of this disclosure is shown. Detailed Implementation

[0029] Embodiments of this disclosure will now be described in more detail with reference to the accompanying drawings. While some embodiments of this disclosure are shown in the drawings, it should be understood that this disclosure can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of this disclosure. It should be understood that the accompanying drawings and embodiments of this disclosure are for illustrative purposes only and are not intended to limit the scope of protection of this disclosure.

[0030] The embodiments of this disclosure provide a novel method and apparatus for determining spot condition based on goodness-of-fit (GOF). Here, as used herein, the term "spot condition" includes, but is not limited to, the morphology, size, energy distribution, and center of the spot. As described in the background art, measurements of spot condition, such as spot morphology and size, are typically determined using Gaussian fitting methods. However, in cases of abnormal spot conditions (e.g., the presence of tailing or other noise), the spot condition determined by Gaussian fitting methods may lead to deviations in the final measurement results in engineering applications.

[0031] Therefore, the inventors of this disclosure unexpectedly discovered that the unfavorable results of the Gaussian fitting method can be overcome by using the film thickness spectral goodness of fit (GOF), which is closely related to the evaluation of the final measurement results. Specifically, when judging the condition of a light spot using the film thickness spectral goodness of fit, it is first necessary to provide a standard thin film measurement area of ​​a predetermined size with a known thickness, which is significantly larger than the size of the light spot to be measured. It will be understood that when the light spot to be measured is projected onto multiple different points within the standard thin film measurement area, the film thickness-related spectrum of the light reflected from each predetermined point has a film thickness spectral goodness of fit specific to that predetermined point. By utilizing the distribution of multiple film thickness spectral goodness of fits over the standard thin film measurement area, it is possible to evaluate the condition of the light spot to be measured, such as its size, shape, and energy distribution.

[0032] To more clearly understand the principle of the film thickness spectral fit goodness of fit (GOF) method disclosed in this paper, we will first combine it with... Figures 4 to 6 This describes how to use the standard film thickness measurement area 410 to obtain the distribution of film thickness spectral fit goodness in one dimension, and to determine or estimate the condition of the light spot under test in one dimension.

[0033] For example only, Figure 4 A schematic diagram of a thin film structure having a standard film thickness measurement region 410 according to the present disclosure is shown.

[0034] like Figure 4 As shown, the standard film thickness measurement region 410 can be provided by the thin film material 400. According to a pre-design, the thickness and size of the standard film thickness measurement region 410 are known, and its size is significantly larger than the size of the spot to be measured. Typically, in addition to providing the standard film thickness measurement region 410, the thin film material 400 can also provide a peripheral thin film region 420 located around the standard film thickness measurement region 410. This peripheral region 420 can have a thickness significantly different from that of the standard film thickness measurement region 410, thereby facilitating... Figure 1 The measurement device shown identifies the standard film thickness measurement area 410. However, this is not a limitation; in certain specific embodiments, the standard film thickness measurement area 410 may also be equal to the size of the thin film material 400, in which case the aforementioned peripheral thin film area 420 may be provided by another thin film material.

[0035] In some embodiments, the thin film material 400 may be made of a semiconductor material (e.g., silicon wafer). It will be understood that it is convenient to fabricate the standard film thickness measurement area 410 using a semiconductor material, and facilitates the use of materials such as... Figure 1 The measurement equipment shown (e.g., an ellipsometer) performs high-precision measurements of film thickness and goodness of fit because, as Figure 1The measurement equipment shown is typically designed for semiconductor manufacturing processes. However, this is not a limitation; in other embodiments, it is possible to use other thin film materials to provide the film thickness measurement area.

[0036] In some embodiments, the thin film material 400 may provide multiple standard film thickness measurement regions 410 of different sizes, such as two, three, or four standard film thickness measurement regions 410. For example, the size of the standard film thickness measurement region 410 may be, for example, 100 μm × 100 μm, or 150 μm × 150 μm, etc. In this way, the same thin film material 400 can provide standard film thickness measurement regions 410 of corresponding sizes for light spots of different sizes. Furthermore, the shape of the standard film thickness measurement region 410 can be any suitable shape, including but not limited to regular shapes such as rectangles, squares, circles, and ellipses.

[0037] Figure 5 This diagram illustrates an operation for determining the condition of a test spot on a one-dimensional scale based on goodness of fit according to an example embodiment of the present disclosure.

[0038] like Figure 5 As shown, assuming the standard film thickness measurement area 410 is rectangular, when the light spot C to be measured moves relative to the standard film thickness measurement area 410 along the dashed line X, the film thickness spectral fit goodness of fit obtained by the measuring device (e.g., a spectrometer or film thickness measurement device) for each predetermined point will be different when measuring the light reflected from each of the multiple predetermined points. It will be understood that if the entire light spot C to be measured is within the standard film thickness measurement area 410, the obtained film thickness spectral fit goodness of fit will be close to 1. Conversely, if the light spot C to be measured crosses the boundary of the standard film thickness measurement area 410, the obtained film thickness spectral fit goodness of fit will be closer to 0.

[0039] Figure 6 Drawing based on Figure 5 The obtained one-dimensional distribution of the film thickness spectrum fitting goodness of fit. From Figure 6 As can be seen, when the test spot C moves relative to the standard film thickness measurement area 410 along the dashed X direction, the obtained film thickness spectral fit goodness distribution exhibits a flat-topped shape in the middle, with falling edges on both sides. In some embodiments, the X direction can be the major axis direction of the test spot C. In some embodiments, a threshold can be set to define the flat-top size of the obtained film thickness spectral fit goodness distribution. As an example only, the threshold can be set, for example, in the range of 0.8 to 0.98. In still other embodiments, the selection of the threshold can be determined based on actual testing acceptance criteria or experience.

[0040] Easy to understand Figure 6The flat-top size of the film thickness fit goodness distribution obtained in the study corresponds to Figure 5 The distance B of the movement, and the morphology and symmetry of the falling edges on both sides, can be used to characterize the energy distribution and symmetry of the test spot along the X direction. It will also be understood that the size of the test spot C in the one-dimensional dimension of the X direction can be obtained by calculating AB, where A is the size parameter of the standard thin film measurement region 410 along the X direction, and B can be determined by measuring the flat-top size of the film thickness spectral fit goodness distribution.

[0041] The foregoing has described in detail how to obtain a one-dimensional distribution of the film thickness spectral fit goodness of the test spot C in a one-dimensional dimension of a standard thin film measurement area, relating to a predetermined location, and how to further utilize this one-dimensional distribution of the film thickness spectral fit goodness to estimate or determine conditions such as size and morphology of the test spot C. It will also be understood that, in a similar manner, the film thickness spectral fit goodness of the test spot C in a two-dimensional dimension of a standard thin film measurement area can be measured at a predetermined location, and conversely, conditions such as size and morphology of the test spot C in a two-dimensional dimension can be estimated or determined.

[0042] Figure 7 A two-dimensional distribution of the film thickness spectral fit goodness obtained for the test spot according to an example embodiment of this disclosure is shown. It should be noted that... Figure 7 Regions of different depths correspond to goodness-of-fit distributions based on different thresholds, with darker gray areas closer to the center corresponding to higher fit thresholds. It will be understood that, based on this two-dimensional distribution of the film thickness spectral goodness-of-fit, characteristics such as size, shape, energy distribution, and center condition of the test spot C can be determined.

[0043] From the above Figure 6 and Figure 7 The view will also help to understand that whether performing a one-dimensional or two-dimensional measurement of the film thickness spectral fit within the standard thin film measurement area, it is done by illuminating the spot to be measured onto multiple predetermined points within the standard thin film measurement area.

[0044] In some embodiments, a plurality of predetermined points can be formed into a dot matrix within a standard thin film measurement area at predetermined intervals. Therefore, the film thickness spectral fit goodness at corresponding points can be obtained by illuminating (or sequentially illuminating) these points with the light spot to be measured one by one, thereby enabling the plotting of... Figure 6 or Figure 7 The distribution of the film thickness spectral fit goodness is shown in the figure.

[0045] It will be understood that the more uniform the distribution and the more appropriate the spacing of the preset points within the standard thin film measurement area, the more accurate the resulting film thickness spectrum goodness-of-fit distribution map will be. Therefore, in some embodiments, the predetermined spacing between the preset points can be selected within the range of 1 μm to 10 μm. In other embodiments, the lattice of preset points can advantageously be distributed throughout the entire standard thin film measurement area. However, this is not a limitation; in some embodiments, the multiple preset points can be distributed in a ring only near the inner boundary of the standard thin film measurement area. In still other embodiments, the density of the multiple preset points in the central region of the standard thin film measurement area can be less than the density in the region near the boundary of the standard thin film measurement area, thereby allowing for targeted plotting of the goodness-of-fit distribution map for the boundary region of the standard thin film measurement area.

[0046] The movement or scanning of the test spot at multiple predetermined points within the standard thin film measurement area can be achieved by moving the test spot relative to the standard thin film measurement area, or by moving the standard thin film measurement area relative to the test spot. For example, in some embodiments, the test spot can be projected sequentially onto multiple different predetermined points within the standard thin film measurement area by translating the standard thin film measurement area relative to the test spot (i.e., keeping the position of the test spot unchanged while translating the position of the standard thin film measurement area). It will be understood that, compared to moving the test spot, translating the standard thin film measurement area provides a more convenient way to control the movement of the test spot at multiple different predetermined points.

[0047] The following will combine Figure 8 The flowchart of the method for judging spot condition based on goodness of fit (GOF) is used to briefly describe the operation steps of the judgment method disclosed herein.

[0048] like Figure 8 As shown, the method may include:

[0049] In frame 810, the light spot to be tested is projected sequentially onto multiple predetermined points within a standard thin film measurement area of ​​a predetermined size. The predetermined size is larger than the size of the light spot. The standard thin film measurement area is surrounded by an outer thin film area with a known thickness. The film thickness of the outer thin film area is significantly different from the film thickness within the standard thin film measurement area.

[0050] Typically, the light spot to be measured is generated by a light spot generating device. In some embodiments, the light spot generating device may be part of a measuring device (e.g., a film thickness measuring device), which is typically an ellipsometer. A customized standard thin film measurement area may be placed on the sample platform to be measured.

[0051] It will be understood that, in practical applications, it is necessary to inspect the condition of the illumination spot emitted by the measuring device. This condition includes, but is not limited to, the shape, size, energy distribution, and center of the spot.

[0052] The projection operation in box 810 can be achieved, for example, by translating a standard thin film measurement area relative to the spot to be measured (e.g., point-by-point). This translation is possible either by translating the spot to be measured relative to the standard thin film measurement area or by translating the standard thin film measurement area relative to the spot to be measured.

[0053] In some embodiments, the arrangement or distribution of multiple predetermined points within a standard thin film measurement area is uniform. For example, the multiple predetermined points can form a dot matrix within the standard thin film measurement area at predetermined intervals. Furthermore, the dot matrix of predetermined points can be distributed throughout the entire standard thin film measurement area. By appropriately adjusting the predetermined intervals and distribution of the predetermined points within the dot matrix, the plotting of the film thickness fit goodness-of-fit distribution map can be achieved more accurately. As an example only, the predetermined interval can be, for instance, in the range of 1 μm to 10 μm.

[0054] Meanwhile, in other embodiments, uneven arrangement or distribution of the predetermined points is also possible. For example, the density of multiple predetermined points in the middle region of the standard thin film measurement area may be less than the density in the region near the boundary of the standard thin film measurement area. Even further, the multiple predetermined points may be distributed in a ring along only the inner boundary of the standard thin film measurement area.

[0055] In box 820, light reflected from each of the plurality of predetermined points is measured to obtain a film thickness measurement spectrum associated with each predetermined point.

[0056] The steps in this box can be achieved through measurements using a measuring device (e.g., an ellipsometer) or a separate spectrometer. It will be understood that multiple film thickness measurement spectra can be obtained by sequentially irradiating multiple predetermined points.

[0057] In box 830, based on the film thickness measurement spectrum obtained at each predetermined point, the goodness of fit of the film thickness spectrum corresponding to each predetermined point is determined.

[0058] It will be understood that the film thickness within the standard thin film measurement area is known and fixed, therefore its actual film thickness spectrum should also be known and fixed. Therefore, the goodness of fit of the film thickness spectrum at each predetermined point can be obtained by comparing the film thickness measurement spectrum obtained at each predetermined point with the actual film thickness spectrum.

[0059] Next, in box 840, based on the goodness of fit of multiple film thickness spectra derived from the multiple predetermined points, at least one of the morphology, size, energy distribution and center of the test spot is determined.

[0060] See the preceding text for reference. Figures 4 to 7 The description is easy to understand. By selecting a number of appropriate predetermined points, such as at least a number of predetermined points near the boundary of the standard thin film measurement area, a film thickness spectral fit distribution map can be plotted, thereby obtaining an assessment of at least one of the morphology, energy distribution, and center of the light spot to be measured.

[0061] In some embodiments, a suitable threshold for GOF can be defined for the film thickness spectral fit goodness distribution map to determine the top size in the film thickness spectral fit goodness distribution map, wherein the condition of the film thickness spectral fit goodness distribution can be used to indicate or determine at least one of the shape, size, energy distribution and center of the spot to be measured.

[0062] The method for determining spot condition based on Goodness-of-Fit (GOF) distribution of this disclosure has been described in detail above. It will be understood that the GOF-based method of this disclosure can more intuitively reflect the regional distribution, size, and center of the spot that affect the measurement results. Furthermore, the method of this disclosure can combine the spot size with the final measurement results and guide the quality assessment of the measurement system during the production process.

[0063] In contrast, when noise appears at the edge of the light spot, the light spot size calculated by the conventional Gaussian fitting method based on the change in light intensity may include the noise in the light spot range, thus leading to an incorrect judgment of the light spot condition.

[0064] In addition to the aforementioned judgment method, this disclosure may also relate to a detection device for judging the condition of a light spot based on a goodness-of-fit (GOF) distribution. This detection device may include: a measuring device adapted to measure the light reflected from each of the plurality of predetermined points when the light spot to be measured is sequentially projected onto a plurality of predetermined points within a standard thin film measurement area, to obtain a film thickness measurement spectrum associated with each predetermined point; and a processing device configured to be operable to perform the aforementioned judgment method. It will be understood that the measuring device may be a film thickness measuring device (e.g., an ellipsometer) or a separate spectrometer.

[0065] Additionally, this disclosure may also relate to a non-transitory machine-readable storage medium having machine-readable program instructions stored thereon, the machine-readable program instructions being configured to cause a detection device to execute the methods described above.

[0066] Figure 9 A block diagram schematically illustrates at least some of the functions of a processing device suitable for implementing the determination method of embodiments of the present disclosure. For example... Figure 9As shown, the processing device 900 includes a central processing unit (CPU) 901, which can perform various appropriate actions and processes according to computer program instructions stored in read-only memory (ROM) 902 or loaded from storage unit 908 into random access memory (RAM) 903. The RAM 903 can also store various programs and data required for the operation of the device 900. The CPU 901, ROM 902, and RAM 903 are interconnected via bus 904. An input / output (I / O) interface 905 is also connected to bus 904.

[0067] Multiple components in device 900 are connected to I / O interface 905, including: input unit 906, output unit 907, and storage unit 908. Processing unit 901 executes the various methods and processes described above, such as executing the aforementioned methods. For example, in some embodiments, the methods may be implemented as computer software programs stored in a machine-readable medium, such as storage unit 908. In some embodiments, part or all of the computer program may be loaded and / or installed on device 900 via ROM 902 and / or communication unit 909. When the computer program is loaded into RAM 903 and executed by CPU 901, one or more operations of the methods described above may be performed. Alternatively, in other embodiments, CPU 901 may be configured to execute one or more actions of the aforementioned methods by any other suitable means (e.g., by means of firmware).

[0068] It should be further noted that this disclosure can be a method, apparatus, system, and / or computer program product. A computer program product may include a computer-readable storage medium having computer-readable program instructions loaded thereon for performing various aspects of this disclosure.

[0069] Computer-readable storage media can be tangible devices capable of holding and storing instructions for use by an instruction execution device. Computer-readable storage media can be, for example, but not limited to, electrical storage devices, magnetic storage devices, optical storage devices, electromagnetic storage devices, semiconductor storage devices, or any suitable combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), static random access memory (SRAM), portable compact disc read-only memory (CD-ROM), digital multifunction disc (DVD), memory sticks, floppy disks, mechanical encoding devices, such as punch cards or recessed protrusions storing instructions thereon, and any suitable combination thereof. The computer-readable storage media used herein are not to be construed as transient signals themselves, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through waveguides or other transmission media (e.g., light pulses through fiber optic cables), or electrical signals transmitted through wires.

[0070] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0071] Computer program instructions used to perform the operations of this disclosure may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, status setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may execute entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing the status information of the computer-readable program instructions to implement various aspects of this disclosure.

[0072] Various aspects of this disclosure are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this disclosure. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0073] These computer-readable program instructions can be provided to a processor in a voice interaction device, a general-purpose computer, a special-purpose computer, or a processing unit of another programmable data processing device, thereby producing a machine such that, when executed by the processing unit of the computer or other programmable data processing device, these instructions create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing device, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0074] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0075] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of devices, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction containing one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0076] Furthermore, it will be understood that the process described above is merely an example. Although the steps of the method are described in a specific order in the specification, this does not require or imply that these operations must be performed in that specific order, or that all the operations shown must be performed to achieve the desired result. On the contrary, the order in which the steps are described can be changed. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into one step, and / or one step may be broken down into multiple steps.

[0077] While the invention has been detailed and described in the accompanying drawings and foregoing description, these descriptions and descriptions should be considered illustrative or exemplary rather than restrictive; the invention is not limited to the disclosed embodiments. Other variations of the disclosed embodiments will be understood and practiced by those skilled in the art in practicing the claimed invention through study of the drawings, disclosure, and appended claims.

[0078] In the claims, the word "comprising" does not exclude other elements, and the indefinite articles "a" or "an" do not exclude a plurality. A single element or other unit may fulfill the function of multiple items set forth in the claims. The mere fact that certain features are recited only in dissimilar embodiments or dependent claims does not imply that combinations of these features cannot be used advantageously. Without departing from the spirit and scope of this application, the scope of protection of this application covers any possible combination of the various features recited in the various embodiments or dependent claims.

[0079] Furthermore, any reference numerals in the claims should not be construed as limiting the scope of the invention.

Claims

1. A method for determining spot condition based on goodness-of-fit (GOF), characterized in that, include: The light spot to be tested is projected sequentially onto multiple predetermined points within a standard thin film measurement area of ​​a predetermined size. The predetermined size is larger than the size of the light spot to be tested. The standard thin film measurement area is surrounded by an outer thin film area with a known thickness. The film thickness of the outer thin film area is significantly different from the film thickness within the standard thin film measurement area. Measure the light reflected from each of the plurality of predetermined points to obtain a film thickness measurement spectrum associated with each predetermined point; Based on the film thickness measurement spectrum obtained at each predetermined point, determine the goodness of fit of the film thickness spectrum corresponding to each predetermined point; as well as Based on the goodness of fit of multiple film thickness spectra derived from the multiple predetermined points, at least one of the morphology, size, energy distribution, and center of the light spot to be tested is determined.

2. The method according to claim 1, wherein the plurality of predetermined points form a dot matrix within the standard thin film measurement area at predetermined intervals.

3. The method according to claim 2, wherein the dot matrix is ​​distributed throughout the standard thin film measurement area.

4. The method according to claim 1, wherein the plurality of predetermined points are distributed in a ring along the inner boundary of the standard thin film measurement area.

5. The method according to claim 1, wherein the density of the plurality of predetermined points in the middle region of the standard thin film measurement area is less than the density in the region near the boundary of the standard thin film measurement area.

6. The method according to claim 2, wherein the predetermined interval is in the range of 1 μm to 10 μm.

7. The method of claim 1, wherein determining at least one of the morphology, size, energy distribution, and center of the light spot to be measured based on multiple goodness-of-fit values ​​derived from the plurality of predetermined points comprises: Determine the threshold for the goodness of fit of the film thickness spectrum; as well as Based on the goodness of fit of the film thickness spectrum at multiple predetermined points greater than the threshold, at least one of the morphology, size, energy distribution, and center of the light spot to be tested is determined.

8. The method of claim 7, wherein the threshold is in the range of 0.8 to 0.

98.

9. The method according to claim 1, wherein projecting the light spot to be measured sequentially onto a plurality of predetermined points within a standard thin film measurement area of ​​a predetermined size comprises: By translating the standard thin film measurement area relative to the light spot to be tested, the light spot to be tested is projected sequentially onto multiple different predetermined points in the standard thin film measurement area.

10. The method according to any one of claims 1-9, wherein the standard thin film measurement area is a rectangular area.

11. A detection device for determining spot condition based on goodness-of-fit (GOF), comprising: A measuring device adapted to measure the light reflected from each of the multiple predetermined points when a light spot to be measured is successively projected onto multiple predetermined points within a standard thin film measurement area, so as to obtain a film thickness measurement spectrum related to each predetermined point. as well as A processing device configured to operate to perform the method according to any one of claims 1-8.

12. A non-transitory machine-readable storage medium having stored thereon machine-readable program instructions configured to enable the method according to any one of claims 1-10 to be executed.

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