Spectral ellipsometry detection system and detection method

Abstract

The invention discloses a spectrum ellipsometry detection system and method based on a digital micromirror device. The system comprises a light source, a polarization state analysis unit, a spatial light modulator, at least one detector and a control unit. And the control unit is configured to load a programmable mask pattern to the spatial light modulator, and can dynamically optimize and switch the pattern based on feedback, so that the analyzed light beam is dynamically routed to different optical paths, and time-sharing or synchronous data acquisition is realized. According to the method, sample information is determined based on a routed optical signal through repeated acquisition and pattern control. According to the invention, the programmability of the spatial light modulator is utilized, the limitation of traditional fixed beam splitting is broken through, the adaptive distribution of light intensity is realized, samples with different reflectivity are adapted, the saturation of the detector is prevented, the signal-to-noise ratio is improved, and the dynamic range and efficiency of measurement are obviously improved.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing technology, and specifically relates to a spectral ellipticity detection system and detection method. Background Technology

[0002] In the field of spectral measurement, especially in applications requiring wide spectral coverage, the key challenge lies in efficiently, rapidly, and stably acquiring data in the visible and near-infrared bands. Currently, mainstream solutions fall into two main categories: single-spectrometer sequential measurement schemes and multi-spectrometer parallel measurement schemes. Single-spectrometer schemes acquire data sequentially by mechanically rotating optical elements or switching measurement bands. While structurally simple, they suffer from slow measurement speeds and data time lags, making them unsuitable for dynamic process monitoring or scenarios with high sample stability requirements. Multi-spectrometer parallel schemes use beam splitters to distribute light to spectrometers in different bands. While enabling synchronous measurement, they introduce inherent light energy loss from the beam splitter, leading to a decrease in the system's signal-to-noise ratio. Furthermore, multiple optical paths require precise alignment and long-term maintenance, resulting in complex calibration and susceptibility to environmental disturbances, leading to reduced measurement accuracy and instability, and increasing system cost and size.

[0003] Therefore, how to ensure measurement speed and wide spectral coverage while taking into account high signal-to-noise ratio, simple structure and long-term reliability, and achieve efficient routing and switching of probe light between multiple measurement channels has become an important technical problem that needs to be solved by those skilled in the art.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a spectral ellipsometry detection system and method that, while ensuring measurement speed and wide spectral coverage, also takes into account high signal-to-noise ratio, simple structure and long-term reliability, and achieves efficient routing and switching of probe light among multiple measurement channels.

[0006] To achieve the above objectives, the present invention provides a method for detecting spectral ellipsoid deviation, comprising the following steps:

[0007] S1 provides incident light with a polarization state to the sample under test;

[0008] S2, perform polarization state analysis on the reflected light from the sample to be tested, and output the analyzed beam;

[0009] S3, repeat the data acquisition loop N times, where N≥1, each loop includes:

[0010] A preset or dynamically generated mask pattern is loaded into a spatial light modulator to selectively route the analyzed light beam to different optical paths, and at least one detector is triggered to perform a data acquisition on the routed light signal in a synchronous measurement mode or a time-division measurement mode.

[0011] S4. Based on the data collected in N cycles, determine the information of the sample to be tested.

[0012] Optionally, before performing step S3, the method further includes: loading an initial mask pattern onto the spatial light modulator; acquiring signal strength collected from at least one of the detectors; and generating an optimized mask pattern based on the signal strength; wherein the mask pattern loaded in step S3 is the optimized mask pattern.

[0013] Optionally, before performing step S3, the method further includes: acquiring an image of the sample to be tested; generating a region selection mask pattern based on the image; the region selection mask pattern being configured such that the spatial light modulator routes the optical signal from a selected region on the surface of the sample to the detector only.

[0014] Optionally, in the synchronous measurement mode, a mask pattern is loaded to maintain a preset optical path allocation state, thereby simultaneously routing the analyzed beam to multiple different optical paths and controlling multiple detectors to acquire data simultaneously.

[0015] Optionally, in the time-division measurement mode, the switching of different optical paths is achieved by one of the following methods: a) sequentially loading and switching to the global operating state of the spatial light modulator to guide the optical signal to different detectors; or b) keeping the spatial mask pattern loaded onto the spatial light modulator unchanged, and sequentially turning on or off the acquisition function of different detectors; c) sequentially switching different mask patterns loaded onto the spatial light modulator to change the gating area or allocation ratio of the optical signal.

[0016] Optionally, the loaded mask pattern defines a reference functional area for routing a portion of the analyzed beam to a reference detector to monitor intensity fluctuations of the light source.

[0017] This application also proposes a spectral ellipsometry detection system, comprising:

[0018] A light source module, which provides polarized incident light to the sample under test;

[0019] A polarization state analysis unit is disposed in the optical path of the reflected light from the sample under test, and is used to analyze the polarization state of the reflected light and output the analyzed beam.

[0020] At least one DMD micromirror is configured to receive the analyzed beam and to load a preset or dynamically generated mask pattern in response to a control command to selectively route the analyzed beam to different optical paths; the mask pattern is a single functional area or is divided into complementary first and second functional areas.

[0021] At least one detector is configured to acquire data on optical signals routed by the DMD micromirrors;

[0022] A control unit, which is electrically connected to the DMD micromirror and the detector, is configured to perform the spectral ellipsometric detection method described above.

[0023] Optionally, the system includes multiple detectors, and the multiple detectors are configured in any of the following ways: a) a combination of multiple spectrometers; b) a combination of at least one spectrometer and at least one photodiode.

[0024] Optionally, the control unit is configured to optimize the mask pattern loaded onto the DMD micromirror based on feedback signals acquired from the detector; the optimization configuration includes at least one of the following: a) adjusting the relative area ratio between functional regions corresponding to different optical paths in the mask pattern; b) generating multiple different mask patterns for sequential loading in time-division measurement mode.

[0025] Optionally, the at least one DMD micromirror includes at least a first DMD micromirror and a second DMD micromirror. The first DMD micromirror is configured to perform primary spatial separation on the analyzed beam and guide at least one separated beam to the second DMD micromirror. The second DMD micromirror is configured to perform secondary spatial separation and routing on the beam from the first DMD micromirror. The system is configured to allow beams separated by any of the first-level DMD micromirrors to be guided to subsequent DMD micromirrors for further separation and routing.

[0026] As described above, this application discloses a spectral ellipsometric detection system and method. The system includes: a light source providing polarized incident light, a polarization state analysis unit for analyzing the polarization state of reflected light from a sample, at least one DMD micromirror, at least one detector, and a control unit. The control unit is configured to load and switch different programmable mask patterns onto the DMD, and to dynamically optimize the mask patterns based on feedback signals. By loading these patterns, the system can dynamically and selectively route the polarization-state analyzed beam to different optical paths, and can synchronously or time-divisionally trigger the detector to acquire data. This method determines sample information based on the beam data routed by the DMD micromirror by repeatedly executing the acquisition cycle. This application utilizes the programmability of the DMD to overcome the limitations of traditional fixed beam splitters, enabling dynamic adjustment of the light intensity distribution of each optical path, thereby adapting to different samples with high or low reflectivity, effectively preventing detector saturation and optimizing the signal-to-noise ratio, achieving a significant improvement in measurement dynamic range and efficiency. Attached Figure Description

[0027] Figure 1 The diagram shown is a flowchart of the spectral ellipsometry detection method in an embodiment of the present invention.

[0028] Figure 2 The diagram shown is a schematic representation of the spectral ellipticity detection system in an embodiment of the present invention.

[0029] Figure 3 The diagram shown is a schematic representation of the structure when a DMD micromirror is formed and the light is directed to the detector in an embodiment of the present invention.

[0030] Figure 4 The diagram shows the structure of the DMD micromirror formed in this embodiment of the invention when the ratio of the first functional region and the second functional region changes before and after the change.

[0031] Figure 5 The diagram shown is a structural schematic of the DMD micromirror in an embodiment of the present invention when it has a single functional area.

[0032] Figure 6 Displayed as the corresponding embodiment of the present invention Figure 5 Timing diagram in single-function time-division measurement mode.

[0033] Figure 7 The diagram shows the structure of the DMD micromirror in an embodiment of the present invention when it is in the form of a first functional area and a second functional area.

[0034] Figure 8 The diagram shows a structural schematic of the first and second functional regions in the DMD micromirror in an embodiment of the present invention when they present different shapes.

[0035] Figure 9 Shown as an embodiment of the present invention Figure 7 and Figure 8 The timing diagrams for the two functional time-division measurement modes are shown in the image.

[0036] Figure 10 The diagram shown is a schematic diagram of the structure of a multi-level DMD micromirror assembly in an embodiment of the present invention.

[0037] Figure 11 The diagram shows a process flow of the system automatically collecting visible and near-infrared light to measure samples in an embodiment of the present invention.

[0038] Figure 12 This diagram illustrates the process of system integration feedforward optimization function performing detection in an embodiment of the present invention.

[0039] Explanation of reference numerals in the attached figures

[0040] 100 Sample to be tested 200 Light source module 210 Incident light 310 Polarization state analysis unit 320 DMD Microscope 321 First DMD Microscope 322 Second DMD micromirror 330 detector 331 First Spectrometer 332 Second Spectrometer 400 Motion control system 510 Reflected light 520 Analyzed beam 530 light signal Detailed Implementation

[0041] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0042] In the detailed description of embodiments of the present invention, for ease of explanation, the cross-sectional views illustrating the device structure may be partially enlarged and not to scale. Furthermore, the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. In actual fabrication, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0043] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include orientations of the device in use or operation other than those depicted in the drawings, and may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact. Furthermore, when a layer is referred to as “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0044] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0045] Example 1

[0046] This embodiment provides a spectral ellipticity detection system. Figure 2 This diagram illustrates the key structures within the system. (See attached diagram.) Figures 2 to 12 The spectral ellipsoid detection system is described below. The spectral ellipsoid detection system includes: a light source module 200, a polarization state analysis unit 310, at least one DMD micromirror 320 (using a digital micromirror device DMD as an example, hereinafter referred to as DMD micromirror), at least one detector 330, and a control unit (unidentified).

[0047] The light source module 200 is used to provide polarized incident light 210 to the sample 100 under test.

[0048] For details, please refer to Figure 2 The light source module 200 is used to provide incident light 210 with a specific polarization state to the sample 100 under test. In a specific embodiment, the light source module 200 includes a light-emitting unit, a collimating element, and a polarizer arranged in sequence. The light-emitting unit (e.g., an LED or a laser) emits an initial beam; this beam is first collimated by the collimating element (e.g., a collimating lens or lens group) to form a parallel beam; subsequently, the parallel beam is converted into the desired linearly polarized light by the polarizer (e.g., a linear grid polarizer or a polarizing prism), and finally illuminates the sample 100 under test with this polarization state.

[0049] The polarization state analysis unit 310 is disposed in the reflected light 510 path of the sample to be tested 100, and is used to analyze the polarization state of the reflected light 510 and output the analyzed beam 520.

[0050] Specifically, the polarization state analysis unit 310 is located in the optical path of the reflected light 510 of the sample 100 under test, and outputs the analyzed beam 520 to the subsequent DMD micromirror 320. The polarization state analysis unit 310 includes an analyzer but does not include a polarization beam splitter.

[0051] The DMD micromirror 320 is configured to receive the analyzed beam 520 and to load a mask pattern in response to a control command, selectively distributing the analyzed beam 520 to different optical paths; the mask pattern is a single functional area or divided into complementary first and second functional areas.

[0052] For details, please refer to Figure 3 The DMD micromirror 320 integrates an array of hundreds of thousands to millions of tiny, independently controllable mirrors on its surface. Each micromirror can switch between two stable deflection angles (e.g., +12° "on" and -12° "off") according to control commands, thereby reflecting light to an effective optical path or optical trap. The control unit controls the loading of a mask pattern onto the DMD micromirror 320, defining the on / off state of the micromirror array and enabling precise control of optical path allocation. The mask pattern can be configured as a single functional area for time-division multiplexing or divided into complementary first and second functional areas for synchronous measurement. In this way, the DMD micromirror 320 acts as a programmable spatial optical router, selectively allocating the incident analyzed beam 520 to different optical paths.

[0053] The detector 330 is configured to acquire data from the optical signal 530 routed by the DMD micromirror 320.

[0054] For details, please refer to Figure 2 The detector 330 is used to acquire the optical signal 530 routed by the DMD micromirror 320. Data acquisition includes performing an exposure process, which includes integrating the signal within a set exposure time, and reading and outputting the integrated signal value after the exposure. Based on the signal strength fed back from the detector 330, the mask pattern of the DMD micromirror 320 is dynamically adjusted to optimize the signal-to-noise ratio and prevent saturation.

[0055] The control unit is electrically connected to the DMD micromirror 320 and the detector 330, and operates the DMD micromirror 320 and the detector 330 to work together to obtain polarization state parameters and determine sample information.

[0056] Specifically, the control unit is electrically connected to the DMD micromirror 320 and the detector 330 via a data bus. This connection enables the control unit to perform its control function: sending mask pattern commands to the DMD micromirror 320; triggering the detector 330 to acquire data; receiving the acquired data; calculating the ellipsoid parameters (Ψ, Δ) based on the acquired data; and determining the thickness and optical constants of the sample 100 to be tested.

[0057] Optionally, as an advanced function, the control unit can dynamically adjust the mask pattern loaded onto the DMD micromirror 320 in subsequent cycles based on the signal strength fed back from the detector 330, in order to optimize the signal-to-noise ratio of each channel and prevent the detector 330 from saturating. As the control core of the system, the control unit's operating logic is not limited to simple timing control; it can process the intensity signal from the detector 330 and calculate the mask pattern for energy optimization accordingly. Simultaneously, it can also process image data from the auxiliary imaging module and map it into a mask pattern for spatial gating, thereby greatly expanding the system's application range and measurement accuracy. The system thus utilizes the DMD micromirror 320 as a programmable spatial light modulator, ultimately achieving dynamic and precise control of the optical path allocation.

[0058] As an example, the system includes multiple detectors 330, and the multiple detectors 330 are configured in any of the following ways: (a) a combination of multiple spectrometers; (b) a combination of at least one spectrometer and at least one photodiode.

[0059] Specifically, the system supports flexible multi-detector 330 configuration schemes, including two modes: (a) combining multiple spectrometers (e.g., using visible and near-infrared spectrometers together) to expand the spectral range and support synchronous or time-division acquisition, thereby efficiently acquiring wide-spectral ellipsometric data; (b) combining at least one spectrometer with at least one photodiode, combining spectral analysis capabilities with rapid light intensity monitoring functions, suitable for dynamic process tracking or light source calibration, significantly expanding the system's application flexibility. In practical applications, the combined detectors 330 can work collaboratively to synchronously acquire compositional information and dynamic characteristics through data fusion, achieving multi-dimensional real-time analysis of complex physical phenomena.

[0060] As an example, the control unit is configured to optimize the mask pattern loaded onto the DMD micromirror 320 based on feedback signals acquired from the detector 330; the optimization configuration includes at least one of the following: (a) adjusting the relative area ratio between functional regions corresponding to different optical paths in the mask pattern; (b) generating multiple different mask patterns for sequential loading in a time-division measurement mode.

[0061] Specifically, in method (a), the control unit automatically calculates and loads a new mask pattern based on the signal strength fed back by the detector 330, aiming to balance the intensity of the optical signal 530 in different optical paths, thereby synchronously optimizing the signal-to-noise ratio of each detection channel and preventing signal saturation. For example, when measuring high reflectivity regions, the proportion of the corresponding functional area is reduced to prevent saturation, while when measuring low reflectivity regions, the proportion is increased to improve the signal-to-noise ratio.

[0062] Furthermore, in semiconductor testing, it is necessary to measure samples with vastly different reflectivities, ranging from highly reflective bare silicon wafers and metal films to low-reflectivity dark photoresists and carbon films. Traditional fixed beam splitter solutions face a dilemma: signal saturation is prone to occur when measuring highly reflective samples, while the signal-to-noise ratio is insufficient when measuring low-reflective samples. (See also...) Figure 4 The example mask pattern consists of two functional areas, A and B. This embodiment perfectly solves this problem by dynamically adjusting the size of the functional areas of the DMD micromirror array 320: when measuring high-reflectivity samples, the micromirror on-state ratio of the corresponding functional area (area A) on the DMD micromirror 320 can be programmably reduced (e.g., from 50% to 10%), effectively preventing detector 330 saturation without changing the light source power and integration time. When measuring low-reflectivity samples, the majority (e.g., 95%) of the image plane area can be allocated to the signal channel to maximize its light throughput and significantly improve the signal-to-noise ratio. This capability allows the system to perform accurate measurements of samples from extremely high to extremely low reflectivity without hardware modifications, and without damage.

[0063] Furthermore, regarding method (b), as a specific embodiment, the control unit can switch between two mask states sequentially: see [link to relevant documentation]. Figure 8 In the first state, the light from the target area of ​​the sample 100 is routed to the detector 330; in the second state, the light from the area surrounding the target area is routed to the same detector 330. By calculating the difference between the two acquired signals and repeating this process multiple times, stray light signals from the area surrounding the target area can be effectively subtracted, significantly improving the accuracy and signal-to-noise ratio of the target area measurement. Detailed control and testing methods will be presented in the third sub-example of Embodiment Two.

[0064] As an example, see Figure 10 The at least one DMD micromirror 320 includes at least a first DMD micromirror 321 and a second DMD micromirror 322. The first DMD micromirror 321 is configured to perform primary spatial separation on the analyzed beam 520 and guide at least one separated beam to the second DMD micromirror 322. The second DMD micromirror 322 is configured to perform secondary spatial separation and routing on the beam from the first DMD micromirror 321. The system is configured to allow beams separated by any of the first-level DMD micromirrors 320 to be guided to subsequent DMD micromirrors for further separation and routing.

[0065] Specifically, the system can be configured with multiple DMD micromirrors 320 to work collaboratively in a cascaded manner. In this architecture, the first DMD micromirror 321 performs primary spatial separation on the analyzed beam 520 and guides one of the optical signals 530 to the second DMD micromirror 322; the second DMD micromirror 322 further performs secondary separation and routing on the beam, and can be expanded to more DMD micromirrors 320 to achieve multi-level optical path control.

[0066] In one specific embodiment, the first DMD micromirror 321 is divided into two functional regions: the first functional region routes the near-infrared component of the incident light 210 to the near-infrared detector 330, and the second functional region guides the remaining light beam to the second DMD micromirror 322. The second DMD micromirror 322 is further divided into two sub-functional regions, which respectively route the ultraviolet light and visible light components to the corresponding detectors 330.

[0067] This multi-level structure supports hierarchical spatial screening from macro to micro and can also be configured as a differential analysis mode that simultaneously measures the test area and the reference area, thereby significantly improving the flexibility of optical path control and spatial resolution, and is suitable for multi-parameter parallel analysis of complex samples.

[0068] As an example, the array of the DMD micromirrors 320 is provided with an optical coating, which is configured to filter the analyzed beam 520 of the polarization state analysis unit 310, and the DMD micromirrors 320 is configured to spatially route the light filtered by the coating.

[0069] Specifically, this configuration integrates spectral filtering and spatial routing functions into the DMD micromirror 320. By depositing different types of optical coatings, such as bandpass, long-wavelength, or short-wavelength passes, on the array of the DMD micromirror 320, the DMD micromirror 320 can simultaneously perform multi-channel, multi-band spectral screening while performing spatial optical routing. This system adopts a highly efficient "filter first, then route" workflow. The analyzed beam 520 is first spectrally purified by the optical coatings on the surface of the DMD micromirror 320, effectively suppressing stray light in non-target bands. Subsequently, the purified beam is precisely routed to the detector 330 according to the mask pattern. This design not only simplifies the system's optical path structure but also ensures the purity of the spectral information of each detection channel from the source, effectively suppressing stray light in non-target bands, thereby significantly improving the signal-to-noise ratio and accuracy of the measurement. It should be understood that the above-described implementation method of depositing bandpass, long-wavelength, or short-wavelength pass coatings is merely an example and is not intended to limit the invention. Those skilled in the art can deposit any type of optical filter coating on the DMD micromirror 320 according to actual measurement needs without departing from the protection scope of the present invention.

[0070] As an example, see Figure 2 The system also includes a motion control system 400 for adjusting the position and orientation of the sample 100 to achieve automated measurement of different areas of the sample surface. The motion control system 400 typically consists of an electric translation stage, a rotary stage, and their controllers, and can work in conjunction with the spectral ellipsometry detection process to achieve point-to-point measurement, array scanning, or specific trajectory scanning of the sample, thereby obtaining the spatial distribution information of the sample. The motion control system 400 is not limited and will not be described in detail here.

[0071] The system utilizes the array of DMD micromirrors 320 to achieve multi-region, multi-parameter parallel high-precision analysis of samples. Its core advantage lies in supporting simultaneous or independent measurements in the visible light (400-800nm) and near-infrared (800-2500nm) bands to meet the diverse analytical needs of complex samples. For the visible light channel, it focuses on high-sensitivity measurements of surface interface properties, suitable for ultrathin layer (<100nm) analysis, accurately characterizing parameters such as surface roughness, ultrathin oxide layer thickness, and shallow doping concentration. For the near-infrared channel, due to its stronger penetration capability, it focuses on measuring bulk structural characteristics, suitable for thicker films (hundreds of nanometers to several micrometers) or transparent films, accurately analyzing overall film thickness, multilayer film structure, and bulk optical constants. This dual-channel synchronous measurement capability is crucial for analyzing complex multilayer film stacks (such as semiconductor gate structures, anti-reflective coatings, OLED layers, etc.), enabling simultaneous acquisition of device surface and interface states and bulk structural information, providing comprehensive data support for process diagnostics and quality control.

[0072] As shown above, this spectral ellipsometric detection system employs an innovative beamsplitter-free optical path design, achieving intelligent control of the optical path through the DMD micromirror 320. During system operation, the polarized light source directly illuminates the sample 100, and the reflected light 510, after polarization analysis, directly reaches the DMD micromirror 320. The DMD micromirror 320 integrates beam steering and optical path distribution functions. By loading different mask patterns, the analyzed beam 520 can be precisely guided to different detection channels, completely avoiding the beamsplitter element essential in traditional optical systems. This simplified optical architecture significantly reduces system complexity while effectively avoiding the light energy loss and polarization interference problems commonly encountered with beamsplitters. The system supports both single-mirror operation and multi-stage combined operation of multiple DMD micromirrors. Combined with a detector array composed of a spectrometer and photodiodes, it achieves multi-channel parallel measurement. Throughout the entire detection process, the control unit coordinates the collaborative work of the DMD micromirror 320 and the detector 330 to ensure precise and controllable operation of the entire process from polarization state analysis to spectral measurement, providing a reliable technical solution for the accurate determination of material optical constants.

[0073] Example 2

[0074] This embodiment provides a spectral ellipticity detection method, which is based on a spectral ellipticity detection system as described in Embodiment 1 or other spectral ellipticity detection systems that can achieve the same function. The following describes the method in conjunction with... Figures 1-12 The method, described in detail below, includes the following steps:

[0075] Reference Figures 1-2 Step S1 is executed, providing incident light 210 with a polarization state to the sample 100 to be tested.

[0076] Specifically, a light source module 200 of the system provides precisely controllable polarized incident light 210 to the sample 100 under test. The light source module 200 is typically composed of a monochromatic or broadband light source and components such as a polarizer and a compensator, and is capable of generating a probe beam with a specific wavelength and a known polarization state (such as linear polarization or ellipsoidal polarization).

[0077] See Figures 1-2 Step S2 is executed to perform polarization state analysis on the reflected light 510 from the sample 100 to be tested, and output the analyzed beam 520.

[0078] Specifically, the polarization state analysis unit 310 of the system receives the reflected light 510 from the sample 100 under test, analyzes the polarization state of the reflected light 510, and outputs the analyzed beam 520. When the incident light 210 with a known polarization state interacts with the sample, its amplitude, phase, and polarization direction change, and these changes reflect the microstructure information of the sample. The polarization state analysis unit 310 provides a direct basis for subsequent quantitative calculation of parameters such as film thickness and optical constants by accurately measuring the change in polarization state of the reflected light 510 (such as ellipticity parameters Ψ and Δ).

[0079] See Figures 1-12 Execute step S3, repeat the data acquisition loop N times, where N≥1. Each loop includes:

[0080] The control unit of the system controls the spatial light modulator of the system (in this embodiment, the DMD micromirror 320 is used as an example) to load a pre-set or dynamically generated mask pattern, selectively route the analyzed beam 520 to different optical paths, and trigger at least one detector 330 to perform a data acquisition on the routed optical signal 530 in synchronous measurement mode or time-division measurement mode.

[0081] Specifically, the core of this loop is that each iteration represents a complete "measurement-acquisition". In this embodiment, the control unit dynamically defines the optical path allocation scheme by configuring a new mask pattern for the DMD micromirror 320. This process is repeated N times, enabling the system to efficiently acquire multiple sets of optical data under different spatial distributions of the beam, providing a rich and reliable data foundation for subsequent calculation of polarization state parameters, improvement of signal-to-noise ratio, or multi-channel analysis. It should be noted that the number of acquisition loops N is an integer greater than or equal to 1. Typically, the value of N depends on the selected measurement mode and the required measurement accuracy. For example, in time-division measurement mode, if four different polarization states need to be measured sequentially, N can be set to 4; in the subsequent dynamic optimization process, N may be a variable that automatically terminates based on signal feedback. Therefore, the "N≥1" in the claims encompasses all the above situations and is fully supported by this specification.

[0082] It is understandable that the core of the above step S3 is "dynamically routing the optical path through a programmable mask pattern". As long as this function can be achieved, the spatial light modulator is not limited to the DMD micromirror 320, but can also use other programmable devices such as liquid crystal spatial light modulator (LCoS).

[0083] Step S4 is executed to determine the information of the sample 100 to be tested based on the data collected in N cycles.

[0084] Specifically, in a preferred embodiment, the control unit can complete the analysis of sample information through a series of signal preprocessing, multi-channel data fusion, and physical model inversion. These steps may include, but are not limited to: first, preprocessing the acquired raw light intensity data, such as filtering and noise reduction and extracting feature parameters (e.g., Ψ(λ) / Δ(λ) in ellipsometric measurement or light intensity distribution in imaging); then, implementing multi-channel data fusion to improve the signal-to-noise ratio, such as integrating data simultaneously acquired by multiple detectors 330 (e.g., stitching visible and near-infrared spectra into a broadband dataset, or associating spatiotemporal features of different modes); finally, inputting the processed feature data into an analytical model. For example, using a physics-based ellipsometric model to invert film thickness and optical constants, or using data-driven calibration orientation to analyze component concentrations, thereby completing the complete analysis from optical signals to sample physical properties.

[0085] It is understood that the above data processing procedure is an efficient and preferred method to achieve the function of "determining sample information". Those skilled in the art will know that, depending on the specific application scenario and accuracy requirements, other equivalent data processing algorithms or models can be used to accomplish this function, and all of these fall within the protection scope of this invention.

[0086] As an example, the system supports two modes: time-sharing measurement mode and synchronous measurement mode.

[0087] In the time-division measurement mode, the control unit, through timing control, routes the analyzed beam 520 to different single optical paths for acquisition at different time periods. This is achieved through one of the following methods: a) sequentially switching to the global operating state of the spatial light modulator to guide the optical signal to different detectors 330; or b) keeping the spatial mask pattern loaded onto the spatial light modulator unchanged while sequentially enabling or disabling the acquisition function of different detectors 330; or c) sequentially switching between different mask patterns loaded onto the spatial light modulator to change the gating region or allocation ratio of the optical signal.

[0088] In the synchronous measurement mode, the control unit controls the DMD micromirror 320 to load the mask pattern, maintains a preset optical path allocation state, and synchronously controls multiple detectors 330 to simultaneously acquire optical signals 530 from different optical paths.

[0089] To achieve synchronous measurement, the system requires multiple detectors 330. As a typical, but not limiting, configuration, the system may include a visible light spectrometer and a near-infrared spectrometer, respectively used to acquire optical signals in different wavelength bands. As a specific example, the control unit controls the DMD micromirrors 320 to load the mask pattern, positioning the micromirror array in the first functional area at +12° to route the light beam to the visible light spectrometer, while simultaneously positioning the micromirror array in the second functional area at -12° to route the light beam to the near-infrared spectrometer. It should be understood that the above specific configuration is merely an example, and the implementation of the invention is not limited to this; the spectrometer is not limited to this.

[0090] The following examples demonstrate the flexibility and intelligence of the spectral ellipsometry detection method in different application scenarios. These examples can be implemented independently or combined according to measurement requirements.

[0091] In the first sub-implementation, taking mode (a) of time-division measurement as an example, the system sequentially switches to the global operating state of the spatial light modulator to guide the optical signal to different detectors 330. The following example illustrates this:

[0092] In scenarios where different detectors 330 are switched, the array of the DMD micromirrors 320 is configured as a complete single functional area, for example, by loading the two typical operating states of "fully on" and "fully off" at different cycles. (See also...) Figure 2 , Figure 5 and Figure 6In the first measurement cycle, the control unit controls the single functional area to be in a first deflection state (e.g., P1 deflection angle is +12° and in ON1 state), routing the optical signal 530 to the first spectrometer 331 for acquisition (time t1). In the second measurement cycle, the control unit controls the single functional area to be in a second deflection state (e.g., P2 deflection angle is -12° and in ON2 state), routing the optical signal 530 to the second spectrometer 332 for acquisition (time t2); this cycle repeats to achieve time-division switching of the optical path between different detectors 330.

[0093] In the second sub-implementation, an example of implementation of method (b) based on time-division measurement mode is provided. The spatial mask pattern loaded onto the spatial light modulator remains unchanged, and the acquisition functions of different detectors 330 are turned on or off sequentially. The system can pre-store one or more such templates (e.g., circular, annular, or multiple discrete regions). In this embodiment, the array of DMD micromirrors 320 is divided into a first functional area and a second functional area, and a fixed mask pattern is loaded and remains unchanged throughout the time-division measurement process. The system activates different optical paths and corresponding detection channels for acquisition in different periods through timing control. The following describes two typical application scenarios:

[0094] (1) In the scenario of multi-detector 330 spectral acquisition, refer to Figure 7 and Figure 9 In the first measurement cycle, the first functional area (corresponding to region A) is in the working state, while the second functional area (corresponding to region B) is in the non-working state. Simultaneously, the first spectrometer 331 is triggered to acquire data (time t3), while the second spectrometer 332 remains in the off or non-acquiring state. In the second measurement cycle, the second functional area (corresponding to region B) is in the working state, while the first functional area (corresponding to region A) is in the non-working state. Simultaneously, the second spectrometer 332 is triggered to acquire data (time t4), while the first spectrometer 331 remains in the off or non-acquiring state. This cycle repeats, achieving time-division measurement of the two spectral channels.

[0095] (2) In a single spatial analysis scenario using the detector 330, there is a one-to-one correspondence between the array of the DMD micromirrors 320 and the imaging surface of the sample 100 under test. For a typical example, see [reference needed]. Figure 8 and Figure 9The first functional area is defined as a circular region (corresponding to region A1 on the sample 100). The second functional area is defined as an annular region (corresponding to region B1 on the sample 100 outside region A1). In the first measurement cycle, the first functional area is in an active state (e.g., +12°), the second functional area is in a non-active state (e.g., -12°), and the detector 330 is triggered to collect data from region A1 (time t5). In the second measurement cycle, the second functional area is in an active state (e.g., +12°), the first functional area is in a non-active state (e.g., -12°), and the detector 330 collects data from region B1 (time t6). Through multiple cycles and comparative analysis, sample information can be obtained.

[0096] It is understood that the implementation of method (b) is not limited to the above configuration, and any variation based on this principle falls within the protection scope of this invention.

[0097] In the third sub-implementation, an implementation example of method (c) based on time-division measurement mode is provided, in which different mask patterns loaded onto the spatial light modulator are switched sequentially to change the gating region or allocation ratio of the optical signal 530. The system pre-stores or generates multiple different mask patterns in real time. During time-division measurement, the control unit loads and switches these different patterns onto the DMD sequentially. After each pattern switch, the corresponding detector 330 is triggered to acquire data, thereby changing the routing or gating region of the optical signal. See also... Figure 8 The system pre-stores two mask patterns: the first pattern on the left is a mask for the circular region A1 of the sample to be tested; the second pattern on the right is a mask for the square region A2 of the sample to be tested. In the first measurement cycle, the control unit loads the first pattern onto the DMD micromirror. At this time, the optical path is configured to route the light from region A1 only to the detector 330, and then acquisition is triggered. In the second measurement cycle, the control unit switches and loads the second pattern onto the DMD micromirror. At this time, the optical path is reconfigured to route the light from region A2 to the same detector 330, and then acquisition is triggered again. By switching the mask patterns sequentially, the system achieves cyclic measurement and comparative analysis of multiple specific regions of the sample using a single detector 330, fully demonstrating the flexibility of programmable spatial light modulation.

[0098] It is understood that the above scenarios collectively demonstrate the core value of methods (a), (b), and (c). The mask pattern is not limited to "fully open / fully closed" or "circular / ring-shaped"; any pattern that can guide the optical signal 530 to different detectors or select different regions of the sample in a predetermined sequence is applicable to this scheme.

[0099] Sub-examples one, two, and three above demonstrate the flexible application of the system in time-sharing measurement mode. In contrast, sub-example four demonstrates the high efficiency of the system in synchronous measurement mode.

[0100] In the fourth sub-implementation, an application example based on a synchronous measurement mode is provided. In this mode, the control unit controls the DMD micromirror 320 to load a mask pattern, maintains a preset optical path allocation state, so as to simultaneously route the analyzed beam 520 to multiple different optical paths, and controls multiple detectors 330 to simultaneously acquire the light. As a typical, and not limiting, application example, the system is configured to simultaneously acquire the visible light (Vis) and near-infrared (NIR) spectra of the sample 100 under test. In this example, the DMD micromirror 320 loads a preset mask pattern, dividing the micromirror array into different functional areas (e.g., the first functional area is at +12° corresponding to the visible light channel, and the second functional area is at -12° corresponding to the near-infrared light channel), aiming to achieve synchronous acquisition of the visible light and near-infrared spectra reflected by the sample 100 under test.

[0101] Its complete automated working process, such as Figure 11 As shown, the specific execution is as follows: Starting with system and parameter initialization, after loading a mask pattern defining the Vis and NIR regions onto the DMD, the core synchronous acquisition loop begins. The control unit issues a global synchronization trigger signal, and the array of the DMD micromirrors 320 instantaneously stabilizes at a preset angle within microseconds based on the loaded mask pattern. Simultaneously, the visible light spectrometer and near-infrared spectrometer begin exposure integration synchronously upon receiving the trigger signal, acquiring Vis and NIR signals from different spatial locations, respectively. After a preset exposure time, the spectral data is read to the control unit. Subsequently, the control unit performs a logical judgment to check whether the number of completed acquisitions has reached the preset average number. If the judgment has not reached, the system will immediately or after a set short delay issue the next synchronization trigger signal, repeating this acquisition loop until the cumulative average number is completed. This averaging operation aims to suppress random noise and improve the signal-to-noise ratio of the measurement data. Finally, the control unit terminates the loop, stitches the Vis and NIR spectral data, and uses a fitting algorithm to deduce results such as thickness or optical constants, completing the measurement. This scheme fully demonstrates an advanced acquisition process from high-speed parallel optical path allocation, synchronous triggering, cyclic averaging to data fusion. The corresponding detector 330 can be flexibly configured as needed and is not limited to the visible and near-infrared spectrometers described above. It should be noted that the application of this synchronous measurement mode is far beyond this example. The mask pattern can be programmed to route the beam to two or more channels and is applicable to any scenario requiring parallel acquisition of multiple optical information, such as synchronous measurements of different polarization states, different spatial regions, or other spectral ranges.

[0102] Furthermore, the synchronous detection mode complements the "time-division switching" mode. The time-division measurement mode, thanks to the extremely high switching speed of the DMD micromirror 320, has a measurement interval much smaller than the dynamic change interval of the sample. Therefore, it can also be regarded as "quasi-synchronous" measurement on a macroscopic level, which together ensures the time consistency of multi-channel data.

[0103] In addition to the basic operating mode, the system of this invention also integrates intelligent feedforward optimization functions to further improve measurement quality, as shown in the fifth sub-example below. In the fifth sub-example, see... Figure 12 It also provides that intelligent feedforward optimization steps can be included before executing step S3.

[0104] As an example of one aspect, the step includes: acquiring an image of the sample 100 to be tested and generating a mask pattern based on the image; the DMD micromirror 320 routes the light signal 530 from a selected area on the surface of the sample 100 to the detector 330 only.

[0105] Specifically, in one particular embodiment, see [reference] Figure 8 However, when the area to be measured of the sample 100 is very small (such as a specific part of a micro / nano structure), or when it is necessary to avoid defects on the sample, the system acquires a surface image of the sample 100 through an imaging module (such as a CCD camera) and delineates the region of interest (ROI, region A2) to be measured. Subsequently, the control unit maps the coordinates of the ROI to the DMD micromirror 320 array to generate a corresponding spatial gating mask pattern. In this mask pattern, only the micromirrors located within the ROI are set to the "on" state (e.g., +12°), and the light signal 530 is routed to the spectrometer for acquisition; while all micromirrors outside the ROI (region B2) are set to the "off" state (e.g., -12°), and their reflected light beams are guided to the light trap for absorption. This process can greatly suppress background stray light and significantly improve the spatial resolution and accuracy of the measurement. It should be understood that the above method of delineating the ROI and automatically generating the mask pattern through an auxiliary imaging module is an intelligent and preferred solution for realizing the 'spatial gating' function. The core idea of ​​this invention, 'generating mask patterns based on images,' is not limited to this specific process. It also covers implementation methods that define the selected area through other means (such as pre-storing known patterns, manually specifying areas, etc.).

[0106] As another example, the step further includes: the control unit controls the spatial light modulator (e.g., DMD micromirror 320) to load an initial mask pattern, acquires the signal intensity collected from at least one of the detectors 330, and generates an optimized mask pattern based on the signal intensity; the mask pattern loaded in step S3 is the optimized mask pattern.

[0107] Specifically, in broadband ellipsometers, the uneven intensity distribution of the light source in different wavelength bands (such as visible and near-infrared) and the differences in the sensitivity of the detector 330 often lead to significant differences in signal intensity between different channels. For example, the Vis channel signal may be too strong, while the near-infrared (NIR) channel signal may be too weak. The system evaluates the signal intensity of each channel through pre-scanning. Then, it automatically calculates and loads an optimized mask pattern (e.g., reducing the functional area ratio of the stronger signal channel (e.g., Vis) on the DMD, while increasing the functional area ratio of the weaker signal channel (e.g., NIR)). Through this dynamic spatial energy allocation, the light energy levels received by the two spectrometer detectors tend to be comparable. Therefore, the system can set the same and optimal integration time for both channels, preventing the strong signal channel from saturating while ensuring that the weak signal channel receives enough photons to improve the signal-to-noise ratio, thus achieving truly optimized high-speed parallel measurement. This embodiment clearly demonstrates how to dynamically optimize the mask pattern based on the feedback from the detector 330 to improve system performance. It is understandable that the application of this dynamic optimization is not limited to balancing the energy of different spectral channels; its core idea lies in "adjusting the mask pattern based on the feedback signal to optimize the measurement." Therefore, this optimization strategy is also applicable to other objectives, such as preventing saturation of a single detector, optimizing the light flux of different regions in spatial gating, or obtaining the optimal signal-to-noise ratio through iterative approximation. The optimization algorithms and mask adjustment strategies for implementing this idea are not limited to adjusting the area ratio; they may include other equivalent methods such as changing the switching timing (duty cycle) of the micromirrors.

[0108] In the sixth sub-implementation, a method for real-time calibration by defining a reference functional area is provided.

[0109] As an example, the control unit is configured to define a reference functional area in the spatial light modulator (e.g., DMD micromirror 320) by means of the loaded mask pattern, for routing a portion of the light beam to the photodiode to monitor the light source intensity.

[0110] Specifically, the micromirror array within the reference functional area is permanently locked in the ON state, thereby continuously routing a portion of the analyzed beam 520 to a dedicated photodiode or spectral reference module (with a built-in spectral detection unit), rather than participating in sample measurement. This design constructs a reference optical path independent of the main measurement optical path, the core purpose of which is to monitor the light source intensity in real time and synchronously. Through this mechanism, the system can simultaneously acquire a "measurement signal" containing sample information and a "reference signal" reflecting only the light source intensity in each cycle of detection. Subsequently, the control unit uses the reference signal to standardize the measurement signal (e.g., real-time normalization correction), thereby effectively offsetting intensity drift caused by factors such as light source fluctuations and aging. This ensures that the information of the final extracted sample 100 (such as transmittance, concentration, etc.) reflects only the characteristics of the sample itself, significantly improving the accuracy and reliability of the measurement; this scheme constructs an independent reference optical path, and through real-time monitoring and correction, effectively improves the long-term stability and accuracy of the measurement. It should be noted that the above-mentioned 'permanently locked in the ON state' is a preferred method for achieving a stable and reliable reference optical path. However, the core idea of ​​the present invention of 'defining a reference functional area' is not limited to this. For example, a dynamic but high duty cycle switching mode can also be used to define the reference functional area, as long as it can provide a continuous and stable reference signal.

[0111] In the seventh sub-implementation, see Figure 10 This embodiment provides a multi-level DMD architecture for the spectral ellipsometric detection system. This architecture greatly improves the system's optical path allocation capability and the flexibility of parallel processing tasks. As described above, the system includes at least a first DMD micromirror 321 and a second DMD micromirror 322. The first DMD micromirror 321 is configured to perform primary spatial separation on the analyzed beam 520 and guide at least one separated beam to the second DMD micromirror 322. The second DMD micromirror 322 then performs secondary spatial separation and routing on the beam from the first DMD micromirror 321.

[0112] It is worth emphasizing that this multi-level architecture provides extremely high flexibility for the system's functional design. As mentioned in the fifth sub-implementation above, the reference functional area can be cleverly designed on any level of the DMD micromirror 320 in this multi-level system. Specifically, after primary spatial separation by the first DMD micromirror 321, any optical path output from it can have a dedicated micromirror array designated as the local reference functional area for that branch during secondary processing by subsequent DMD micromirrors 320 (such as the second DMD micromirror 322). This design means that the system can not only perform global monitoring of the total light source at the initial stage of the optical path, but also implement independent intensity monitoring and compensation for specific branches at any branch or level of the optical path. This provides an unprecedented system architecture foundation for achieving complex parallel optical processing and high-precision measurement. It should be understood that this multi-level DMD architecture itself is an important inventive concept, and its scope of protection covers all optical path allocation and control systems based on this architecture. The aforementioned deployment of the reference functional area is merely an example demonstrating the superior flexibility of this architecture, and not a limitation on its application scope.

[0113] It should be emphasized that this embodiment is only used to clearly illustrate the operation flow of the method of the present invention. Those skilled in the art should understand that, without departing from the core principles of the present invention, there may be various variations in the specific implementation of each step in the method.

[0114] In summary, this application discloses a spectral ellipsometric detection system and method. The system includes: a light source providing polarized incident light, a polarization state analysis unit for analyzing the polarization state of reflected light from a sample, a DMD micromirror, at least one detector, and a control unit. The control unit is configured to load and switch different programmable mask patterns onto the DMD, and to dynamically optimize the mask patterns based on feedback signals. By loading these patterns, the system can dynamically and selectively route the polarization-state analyzed beam to different optical paths, and can synchronously or time-divisionally trigger the detector for data acquisition. This method involves repeatedly executing acquisition cycles, with the control unit determining sample information based on the beam data routed by the DMD micromirror. This application utilizes the programmability of the DMD, overcoming the limitations of traditional fixed beam splitters, and can dynamically adjust the intensity distribution of each optical path to adapt to different samples with high or low reflectivity. This effectively prevents detector saturation and optimizes the signal-to-noise ratio, achieving a significant improvement in measurement dynamic range and efficiency.

[0115] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for detecting spectral ellipsoid deviation, characterized in that, Includes the following steps: S1 provides incident light with a polarization state to the sample under test; S2, perform polarization state analysis on the reflected light from the sample to be tested, and output the analyzed beam; S3, repeat the data acquisition loop N times, where N≥1, each loop includes: A preset or dynamically generated mask pattern is loaded into a spatial light modulator to selectively route the analyzed light beam to different optical paths, and at least one detector is triggered to perform a data acquisition on the routed light signal in a synchronous measurement mode or a time-division measurement mode. S4. Based on the data collected in N cycles, determine the information of the sample to be tested.

2. The spectral ellipsoid detection method according to claim 1, characterized in that, Before performing step S3, the method further includes: loading an initial mask pattern onto the spatial light modulator; acquiring the signal intensity collected from at least one of the detectors; and generating an optimized mask pattern based on the signal intensity; wherein the mask pattern loaded in step S3 is the optimized mask pattern.

3. The spectral ellipsoid detection method according to claim 1, characterized in that, Before performing step S3, the method further includes: acquiring an image of the sample to be tested; generating a region selection mask pattern based on the image; the region selection mask pattern being configured such that the spatial light modulator routes the light signal from a selected region on the surface of the sample to the detector only.

4. The spectral ellipsoid detection method according to claim 1, characterized in that: In the synchronous measurement mode, a mask pattern is loaded to maintain a preset optical path allocation state, thereby simultaneously routing the analyzed beam to multiple different optical paths and controlling multiple detectors to acquire data simultaneously.

5. The spectral ellipticity detection method according to claim 1, characterized in that, In the time-division measurement mode, the switching of different optical paths is achieved by one of the following methods: a) sequentially loading and switching to the global operating state of the spatial light modulator to guide the optical signal to different detectors; or b) keeping the spatial mask pattern loaded onto the spatial light modulator unchanged, and sequentially turning on or off the acquisition function of different detectors; c) sequentially switching different mask patterns loaded onto the spatial light modulator to change the gating area or allocation ratio of the optical signal.

6. The spectral ellipsoid detection method according to claim 1, characterized in that, The loaded mask pattern defines a reference functional area for routing a portion of the analyzed beam to a reference detector to monitor intensity fluctuations of the light source.

7. A spectral ellipticity detection system, characterized in that, include: A light source module, which provides polarized incident light to the sample under test; A polarization state analysis unit is disposed in the optical path of the reflected light from the sample under test, and is used to analyze the polarization state of the reflected light and output the analyzed beam. At least one DMD micromirror is configured to receive the analyzed beam and to load a preset or dynamically generated mask pattern in response to a control command to selectively route the analyzed beam to different optical paths; the mask pattern is a single functional area or is divided into complementary first and second functional areas. At least one detector is configured to acquire data on optical signals routed by the DMD micromirrors; A control unit, electrically connected to the DMD micromirror and the detector, and configured to perform the spectral ellipsometric detection method according to any one of claims 1 to 6.

8. The spectral ellipticity detection system according to claim 7, characterized in that: The system includes multiple detectors, and the multiple detectors are configured in any of the following ways: a) a combination of multiple spectrometers; b) a combination of at least one spectrometer and at least one photodiode.

9. The spectral ellipticity detection system according to claim 7, characterized in that: The control unit is configured to optimize the mask pattern loaded onto the DMD micromirror based on feedback signals acquired from the detector; the optimization configuration includes at least one of the following: a) adjusting the relative area ratio between functional regions corresponding to different optical paths in the mask pattern; b) generating multiple different mask patterns for sequential loading in time-division measurement mode.

10. The spectral ellipticity detection system according to claim 7, characterized in that: The at least one DMD micromirror includes at least a first DMD micromirror and a second DMD micromirror. The first DMD micromirror is configured to perform primary spatial separation on the analyzed beam and guide at least one separated beam to the second DMD micromirror. The second DMD micromirror is configured to perform secondary spatial separation and routing on the beam from the first DMD micromirror. The system is configured to allow beams separated by any of the first-level DMD micromirrors to be guided to subsequent DMD micromirrors for further separation and routing.

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