A multi-zone real-time end point detection system and method for semiconductor chamber cleaning

Abstract

The application discloses a kind of multi-zone real-time endpoint detection system and method for semiconductor chamber cleaning, it is related to semiconductor gas detection field, gas path unit, with total gas inlet, first branch, second branch and for the valve module of the first branch or second branch is opened or closed;First chamber, opposite first broadband light source and first multi-channel photoelectric detector are arranged on two sides, and the filter of different center wavelength is configured in multiple channels of first multi-channel photoelectric detector;Multiple second photoelectric detectors, multiple target light sources and displacement platform are oppositely arranged on two sides of second chamber, and multiple target light sources are installed on displacement platform and can be moved relative to second photoelectric detector;Control module is signal connected with valve module, first multi-channel photoelectric detector, displacement platform and each target light source.Using the above scheme, while ensuring the detection accuracy, detection efficiency is also considered, and more reliable real-time endpoint determination can be realized in complex gas flow field environment.

Description

Technical Field

[0001] This invention relates to the field of semiconductor gas detection technology, and in particular to a multi-region real-time endpoint detection system and method for semiconductor chamber cleaning. Background Technology

[0002] As semiconductor manufacturing processes continue to evolve towards smaller feature sizes, higher integration levels, and more complex structures, the requirements for chamber cleanliness and process stability in key processes such as plasma etching and chemical vapor deposition are constantly increasing. Under conditions of prolonged exposure to high-energy plasma and deposition of reaction byproducts, residual deposits can easily form on the inner walls of the process chamber and the surfaces of critical components. If these layers are not removed in a timely and sufficient manner, they will directly affect the consistency, yield, and operational reliability of subsequent processes. Therefore, semiconductor manufacturing equipment typically needs to perform chamber cleaning processes at specific process stages or batch intervals, and the endpoint of the cleaning process must be accurately determined to avoid process risks caused by over-cleaning or under-cleaning.

[0003] Existing chamber cleaning endpoint detection technologies largely rely on monitoring reaction products or characteristic gases in the cleaning exhaust gas, such as optical absorption, spectral analysis, or single-path gas concentration detection, to determine whether the cleaning reaction has ended. In actual process scenarios, influenced by chamber structure, gas path layout, and flow field conditions, the exhaust gas during cleaning typically exhibits a non-uniform distribution across its cross-section. Furthermore, chamber cleaning exhaust gas often contains multiple reaction gases and intermediate products, with different gases corresponding to different characteristic absorption bands. In existing technologies, detection systems typically preset fixed detection bands before the process begins or rely on manual experience to select detection parameters. When the type of cleaning gas changes, it is often necessary to readjust the light source wavelength or replace the detection module, resulting in long debugging cycles, poor adaptability, and difficulty in meeting the demands for rapid deployment and stable detection under frequent process changes. Existing detection schemes often acquire gas concentration information based on a single optical path or a limited number of detection points, and their results are easily affected by local concentration fluctuations, making it difficult to accurately reflect the true gas concentration level of the overall system or key areas.

[0004] Therefore, there is an urgent need to provide a multi-region real-time endpoint detection system and method for semiconductor chamber cleaning, in order to solve the technical problem of how to effectively suppress the impact of gas space inhomogeneity on detection accuracy without significantly increasing system complexity and detection efficiency. Summary of the Invention

[0005] The purpose of this invention is to provide a multi-region real-time endpoint detection system and method for semiconductor chamber cleaning, in order to solve the technical problem in the prior art of how to effectively suppress the influence of gas space non-uniformity on detection accuracy without significantly increasing system complexity and detection efficiency.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] In a first aspect, a multi-region real-time endpoint detection system for semiconductor chamber cleaning includes:

[0008] The air circuit unit is equipped with a main air inlet, a first branch, a second branch, and a valve module for opening or closing the first branch or the second branch;

[0009] A first chamber is connected to the first branch. A first broadband light source and a first multi-channel photodetector are arranged opposite each other on both sides of the first chamber. The multiple channels of the first multi-channel photodetector are respectively configured with filters of different center wavelengths.

[0010] The second chamber is connected to the second branch. Multiple second photodetectors, multiple target light sources and a displacement platform are arranged opposite each other on both sides of the second chamber. The multiple target light sources are installed on the displacement platform and can move relative to the second photodetectors.

[0011] The control module is connected to the valve module, the first multi-channel photodetector, the displacement platform, and each of the target light sources.

[0012] The displacement platform includes a target working position. Any of the target light sources can move on the displacement platform to the target working position and be optically aligned with the second photodetector to form a measurement optical path. Multiple target light sources can cooperate with multiple second photodetectors to form a uniformly distributed multi-region detection channel.

[0013] Furthermore, the displacement platform includes a base and a guide rail network disposed on the base. The target working position is located on the guide rail network. The guide rail network is composed of multiple linear guide rails connected in an interlaced manner to form multiple displacement paths that allow the target light source to move to the target working position. The target light source is movably disposed on the guide rail network.

[0014] Furthermore, the target light source is a narrow-band light source group with the same center wavelength, and the narrow-band light source group includes multiple detection light sources uniformly distributed along a direction perpendicular to the base.

[0015] Furthermore, the number of channels in the first multi-channel photodetector is greater than the number of channels in the target light source.

[0016] Furthermore, the gas path unit also includes a gas mixer disposed between the main air inlet and the first branch and the second branch, wherein the gas mixer is provided with a turbulence channel and a number of nanoporous medium homogenization sections in sequence along the airflow direction.

[0017] Furthermore, the turbulence channel is a serpentine meandering channel, and the inner wall of the turbulence channel is provided with periodic nanosphere textured protrusions, which are used to generate local disturbances in the airflow near the wall region.

[0018] Furthermore, the porous medium homogenization section is a cylindrical nanoporous material filled in the internal cavity of the gas mixer, including silica aerogel, carbon aerogel, or metal-organic nanopores.

[0019] Furthermore, it also includes a second broadband light source disposed in the second chamber and movable on the guide rail network. The second broadband light source can be moved to the target working position. The second broadband light source includes a calibration guide rail and a light source body. The calibration guide rail extends in a direction perpendicular to the base, and the light source body slides in conjunction with the calibration guide rail.

[0020] Secondly, a multi-region real-time endpoint detection method for semiconductor chamber cleaning, used in the multi-region real-time endpoint detection system for semiconductor chamber cleaning as described above, includes the following steps:

[0021] Control the gas path unit to open the first branch and introduce the process gas to be tested into the first chamber;

[0022] The first broadband light source is activated, and the optical signals of each channel are simultaneously acquired using the first multi-channel photodetector.

[0023] Analyze the signal changes in each channel, and identify the target gas type and its corresponding characteristic absorption wavelength in the current process environment based on the preset gas absorption spectrum feature library.

[0024] The gas path unit is controlled to switch to conduct the second branch. Based on the identified target gas type and characteristic absorption wavelength, a target light source whose emission wavelength matches the characteristic absorption wavelength is selected from multiple target light sources installed on the displacement platform.

[0025] The displacement platform is controlled to move the selected target light source to the target working position and optically align it with the corresponding second photodetector to form a specific measurement optical path for the target gas.

[0026] During the process, process gas is introduced into the second chamber, and the concentration change of the target gas is monitored in real time based on the measurement optical path. The process endpoint is determined based on the concentration change trend.

[0027] Furthermore, before controlling the gas path unit to activate the first branch, a pre-zero point calibration step is included, which includes:

[0028] The first chamber is calibrated using the first broadband light source;

[0029] The displacement platform includes a guide rail network, on which a second broadband light source is disposed. The second chamber is calibrated using the movable second broadband light source located on the guide rail network.

[0030] Furthermore, the calibration of the first chamber using the first broadband light source specifically includes the following steps:

[0031] The gas circuit unit is controlled to introduce calibration gas into the first chamber;

[0032] The first broadband light source is activated, and the optical signals of each channel are synchronously acquired using the first multi-channel photodetector to obtain the reference signals of each channel of the first chamber corresponding to the first broadband light source.

[0033] Furthermore, the calibration of the second chamber using a movable second broadband light source located on the guide rail network includes:

[0034] The gas circuit unit is controlled to introduce calibration gas into the second chamber;

[0035] Control the second broadband light source to move to a target working position;

[0036] The second broadband light source is moved so that the broadband light emitted by the broadband light source is optically aligned with a plurality of second photodetectors in sequence;

[0037] At each alignment position, the optical signal of the corresponding second photodetector is acquired to obtain the reference signal of each measurement channel in the second chamber.

[0038] The beneficial effects of the multi-region real-time endpoint detection system and method for semiconductor chamber cleaning provided by this invention are as follows: By setting a first branch and a second branch in the gas path unit, and connecting them to a first chamber and a second chamber with different functions respectively, the clean gas can be processed in stages during the detection process. Specifically, the first chamber uses a first broadband light source and a multi-channel photodetector equipped with filters of different center wavelengths to collect multi-band optical responses of the clean gas. This allows for the acquisition of gas characteristic information without relying on a preset single detection band, providing a basis for selecting the target detection wavelength in subsequent detection stages. This avoids repeated adjustments to detection parameters due to uncertain gas types and effectively shortens the detection debugging and switching time. Furthermore, in the second chamber, multiple target light sources are mounted on a displacement platform, and their movement is limited to the target working position to form an optically aligned measurement optical path with the corresponding photodetector. This enables the system to quickly establish stable narrow-band detection conditions after determining the target detection wavelength. Simultaneously, by cooperating with multiple target light sources and multiple photodetectors, a multi-region detection channel uniformly distributed along the cross-sectional direction of the second chamber is formed. This eliminates the reliance on gas concentration information from a single spatial location during the detection process, effectively reducing detection errors caused by uneven gas spatial distribution and improving the stability and representativeness of the gas concentration detection results. By adopting the above scheme, this invention ensures both detection accuracy and efficiency, enabling the endpoint detection system to quickly adapt to different clean gas conditions and achieve more reliable real-time endpoint determination in complex gas flow field environments. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of the overall structure of a multi-region real-time endpoint detection system for semiconductor chamber cleaning according to the present invention;

[0040] Figure 2 This is a schematic diagram of the structure of the first multi-channel photoelectric detector according to an embodiment of the present invention;

[0041] Figure 3 This is a schematic diagram of the target light source and the second photodetector inside the second cavity according to an embodiment of the present invention;

[0042] Figure 4 This is a top view of the displacement platform according to an embodiment of the present invention;

[0043] Figure 5 This is a schematic diagram of the narrow-band light source group according to an embodiment of the present invention;

[0044] Figure 6 This is a schematic diagram of the structure of the second broadband light source according to an embodiment of the present invention;

[0045] Figure 7 This is a multi-region average curve of gas concentration changing over time according to an embodiment of the present invention.

[0046] Reference numerals: 1. Main air inlet; 11. First branch; 12. Second branch; 3. First chamber; 31. First broadband light source; 32. First multi-channel detector; 321. Filter; 4. Second chamber; 41. Second photodetector; 42. Target light source; 421. Narrow-band light source group; 43. Displacement platform; 431. Base; 432. Guide rail network; 5. Turbulence channel; 6. Nanoporous medium homogenization section; 7. Second broadband light source; 71. Calibration guide rail. Detailed Implementation

[0047] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.

[0048] Combined with appendix Figure 1 - Appendix Figure 7 The specific embodiments of the present invention will be further described in detail below.

[0049] Reference Figure 1 In some embodiments of the present invention, a multi-region real-time endpoint detection system for semiconductor chamber cleaning is provided. This system monitors process gases generated during chamber cleaning in real time without significantly increasing system complexity or detection time, and reduces the impact of uneven gas spatial distribution on detection accuracy. The multi-region real-time endpoint detection system for semiconductor chamber cleaning includes a gas path unit, a first chamber 3, a second chamber 4, and a control module. These modules cooperate functionally to form a phased, multi-region detection system.

[0050] In some specific embodiments of the present invention, the gas path unit is provided with a main air inlet 1, and is connected to the first branch 11 and the second branch 12 respectively through a valve module. By controlling the conduction state of the valve module, the process gas to be tested can selectively enter the first chamber 3 or the second chamber 4 at different detection stages, thereby realizing staged control of the detection process. This structure allows detection chambers with different functions to work collaboratively in the same system without the need to set up multiple independent detection devices in parallel, which is beneficial to the overall complexity of the system and reduces the volume of the detection structure. In some specific embodiments, the volume of the first chamber 3 is much smaller than the volume of the second chamber 4.

[0051] In some specific embodiments of the present invention, the valve module includes a first valve and a second valve respectively disposed on the first branch 11 and the second branch 12 (e.g., Figure 1 (As shown). And the third and fourth valves (as shown) corresponding to the first chamber 3 and the second chamber 4 respectively. Figure 1 (As shown). The first valve controls the opening and closing of the first branch 11 to allow process gas to be introduced into the first chamber 3; the second valve controls the opening and closing of the second branch 12 to allow process gas to be introduced into the second chamber 4; the third valve is connected to the exhaust end of the first chamber 3 and is used to discharge gas after the first chamber 3 completes the detection; the fourth valve is connected to the exhaust end of the second chamber 4 and is used to adjust the gas state in the second chamber 4 during the endpoint detection process.

[0052] In some specific embodiments, the first valve and the third valve are provided with flange structures (such as...). Figure 1 (The ellipse shown is schematic) to facilitate the sealed connection and quick disassembly between the first chamber 3 and the gas path unit, thereby improving the convenience of system maintenance and replacement. Through the configuration of the above valve module, the first chamber 3 and the second chamber 4 are independent of each other at the gas path level, but can be uniformly dispatched by the same gas source, ensuring the repeatability of detection process switching.

[0053] Reference Figure 1 and Figure 2 In some specific embodiments of the present invention, the first chamber 3 is connected to the first branch 11, and a first broadband light source 31 and a first multi-channel photodetector are arranged opposite each other on both sides of the first chamber 3. The multiple detection channels of the first multi-channel photodetector are respectively equipped with filters of different center wavelengths, so that when the process gas passes through the first chamber 3, the optical response signal of the gas can be acquired simultaneously in multiple wavelength bands. By analyzing the changes in the signals of each channel and combining them with a preset gas absorption spectral feature library, the type of target gas in the current process environment and its corresponding characteristic absorption wavelength can be identified. Since the number of channels of the first multi-channel photodetector is greater than the number of target light sources 42 used for subsequent precise detection, this stage can provide richer spectral information, providing sufficient basis for the selection of subsequent detection wavelengths.

[0054] Reference Figure 2 In some specific embodiments of the present invention, the first multi-channel photodetector includes at least one calibration channel and multiple wavelength analysis channels. The calibration channel is located at the center of the first multi-channel photodetector and is used to acquire a reference optical signal within the first chamber 3. Multiple wavelength analysis channels are distributed around the calibration channel, with their centers located on the same circumference and maintaining the same optical path length as the center of the calibration channel. This channel layout effectively reduces system errors introduced by optical path differences while acquiring optical signals at different center wavelengths. Simultaneously, by optimizing the effective detection area of ​​each wavelength analysis channel, the optical signal acquisition efficiency can be improved within a limited detector size, thereby enhancing the spectral resolution of the first chamber 3 in the gas type identification stage. The first chamber 3 is much smaller than the second chamber 4 and is mainly used for pre-analyzing gas types. Due to its small size, the entire pre-analysis stage is very fast, generally completed within 3-5 seconds, suitable for rapid chamber cleaning processes. To avoid interference from the first broadband light source 31 and subsequent light sources on the gas state and detection process within the chamber, each light source is physically isolated from its corresponding detection chamber. Specifically, high-transmittance optical windows are provided in the corresponding optical paths of the first chamber 3 and the second chamber 4. Lens groups are integrated on the outside of the windows for collimation and focusing of the beam, which ensures efficient transmission of optical signals and airtightness of the chambers, thereby improving the stability and signal accuracy of the system in different detection stages.

[0055] Reference Figures 4-5 In some embodiments of the present invention, the second chamber 4 is connected to the second branch 12. Multiple second photodetectors 41 and multiple target light sources 42 are arranged opposite each other on both sides of the interior of the second chamber 4. The target light sources 42 are mounted on a displacement platform 43 and are movable relative to the second photodetectors 41. The displacement platform 43 includes a base 431 and a guide rail network 432 disposed on the base 431. The guide rail network 432 is composed of multiple linear guide rails connected in an interlaced manner, and a target working position is set on it. The target light source 42 can move along multiple displacement paths formed by the guide rail network 432 to the target working position, and achieve optical alignment with the corresponding second photodetector 41 at that position, thereby forming a stable measurement optical path.

[0056] In some embodiments of the present invention, the target light source 42 is a narrow-band light source group 421 with the same center wavelength, the narrow-band light source group 421 including multiple detection light sources uniformly distributed along a direction perpendicular to the base 431. By ensuring that multiple detection channels differ only in spatial position under consistent spectral conditions, a multi-region detection channel uniformly distributed along the cross-sectional direction of the chamber can be formed within the second chamber 4. Thus, when performing gas concentration detection, detection information from different spatial regions can be acquired simultaneously or equivalently, thereby reducing the impact of gas spatial inhomogeneity on single-point detection results. (Refer to...) Figure 3 A schematic diagram showing the light spots formed by different detection light sources located on the second photodetector.

[0057] In some embodiments of the present invention, the control module is used to jointly analyze the output signals of multiple multi-region detection channels. When the signal of a certain detection channel deviates from the overall trend of the other detection channels during the detection process, the control module can adjust the weight of the signal of that detection channel or remove it based on preset data. At the same time, the control module can also statistically fuse the effective signals of multiple detection channels to obtain the equivalent concentration result characterizing the overall gas state of the second chamber 4. By comprehensively utilizing the signals of multiple region detection channels, the system can maintain a stable judgment ability on the gas concentration change trend even when there are local gas flow field anomalies or transient fluctuations, thereby further suppressing the influence of gas spatial non-uniformity on the endpoint detection accuracy.

[0058] Reference Figure 6 In some specific embodiments of the present invention, a second broadband light source 7, movable along the guide rail network 432, is also provided in the second chamber 4 for calibrating the multi-region detection channels of the second chamber 4. The second broadband light source 7 includes a calibration guide rail 71 extending in a direction perpendicular to the base 431 and a light source body that slides with the calibration guide rail 71. By controlling the second broadband light source 7 to move to different target working positions and sequentially achieving optical alignment with multiple second photodetectors 41, reference signals of each detection channel can be acquired under the same spectral conditions, thereby ensuring the consistency of detection references among the multi-region detection channels. The calibration guide rail 71 extends in a direction perpendicular to the base 431.

[0059] In some specific embodiments of the present invention Figure 4 The schematic diagram of the displacement platform 43 is shown from a top-down perspective, where the base 431 is represented by solid lines, the guide rail network 432 by dashed lines, and multiple target light sources 42 by black square graphic symbols. Each target light source 42 may structurally include multiple detection light sources stacked along a direction perpendicular to the base 431, used to form detection channels distributed along the height direction within the second chamber 4. It should be noted that the number of detection light sources shown in the figure is merely illustrative and does not constitute a limitation of the invention.

[0060] Similarly, Figure 4 The arrangement of the guide rail network 432 shown is only one feasible implementation. Any guide rail structure that can move the target light source 42 or the second broadband light source 7 located at different spatial positions to the target working position and complete optical alignment should be considered to fall within the protection scope of this invention. In some other embodiments, at least one pending working position can be set near the target working position to shorten the moving distance of the target light source 42 or the second broadband light source 7 under conditions of multiple continuous detections or frequent switching of detection channels, thereby further improving the system's response speed and detection efficiency.

[0061] Specifically, the identifiable gas types are:

[0062] wait.

[0063] The characteristic absorption wavelengths and wavelength differences of different target gases are shown in Table 1 below:

[0064]

[0065] in Figure 4 The infrared absorption peaks of different gases and the light source bands corresponding to different narrow-band light source groups 421 are shown in Table 2 below:

[0066]

[0067] In some specific embodiments of the present invention, the gas path unit further includes a gas mixer disposed between the main air inlet 1 and the first branch 11 and the second branch 12. The gas mixer has a turbulence channel 5 and several nanoporous medium homogenization sections 6 arranged sequentially along the airflow direction inside. The turbulence channel 5 is a serpentine meandering channel with periodic nanosphere textured protrusions on its inner wall to generate local turbulence in the near-wall region of the airflow. The porous medium homogenization sections are cylindrical nanoporous materials filled in the internal cavity of the gas mixer; the nanoporous material can be silica aerogel, carbon aerogel, or metal-organic nanopores. Through the synergistic effect of turbulence and porous diffusion, the gas before entering the detection chamber is made more uniform in terms of flow rate and component distribution, thereby further improving the stability of subsequent optical detection results.

[0068] In some specific embodiments of the present invention, a multi-region real-time endpoint detection method based on the above-described system is also provided. The method includes: in the initial detection phase, controlling the gas path unit to activate the first branch 11, allowing process gas to enter the first chamber 3; activating the first broadband light source 31, and simultaneously acquiring multi-band optical signals using a first multi-channel photodetector; identifying the target gas type and its characteristic absorption wavelength by analyzing the signal changes of each channel. Subsequently, controlling the gas path unit to switch to activating the second branch 12, and selecting a target light source 42 from multiple target light sources 42 that matches the characteristic absorption wavelength based on the identification result; controlling the displacement platform 43 to move the target light source 42 to the target working position, forming a specific measurement optical path with the corresponding second photodetector 41. During the process, the concentration change of the target gas is monitored in real time based on the measurement optical path, and the process endpoint is determined based on the concentration change trend.

[0069] In some other embodiments of the present invention, a pre-zero-point calibration step may be performed before the above-described detection process begins. This step includes: using a first broadband light source 31 to perform zero-point concentration calibration on the first chamber 3 to obtain reference signals for each channel; and using a movable second broadband light source 7 disposed on the guide rail network 432 to calibrate each measurement channel of the second chamber 4 one by one. Through this calibration process, the initial response differences between different channels can be effectively eliminated, improving the reliability of endpoint determination.

[0070] Reference Figure 7 Specifically, the first broadband light source 31 is used to perform zero-point calibration on the first multi-channel detector 32 in the first chamber 3, and the data is collected for five minutes before being zeroed. Next, the second broadband light source 7 is moved from its initial position to the target working position via the guide rail network 432 to perform zero-point concentration calibration on multiple second photodetectors 41 in the second chamber 4. Specifically, the second broadband light source 7, with pure nitrogen gas introduced into the second chamber 4, first performs zero-point calibration on the middle channel, then moves via the calibration rail to perform zero-point calibration on the upper and lower channels, collecting data for five minutes before being zeroed. The second broadband light source 7 is then moved back to its initial position via the guide rail network 432 and returned to the middle position of the calibration guide rail 71. Afterwards, the required narrowband light source group 421 is moved to the target working position to begin the formal chamber cleaning endpoint detection, such as... Figure 7 The graph shows the gas concentration changing over time, with the horizontal axis representing time and the vertical axis representing the target gas concentration in the second chamber 4. As time progresses, the gas concentration gradually increases from 0 ppm to a stable level for a period, and then gradually decreases again. The CELAN process cannot be stopped only when the concentration reaches 0 ppm because reaching 0 ppm would result in over-etching and damage to the chamber. Therefore, a set value indicating a stable decrease to 0 ppm is chosen as the cleaning endpoint (e.g., [missing value]). Figure 7(As shown by the dots), the cleaning endpoint can be selected as a set percentage or a fixed value of the maximum concentration.

[0071] Specifically, a narrow-band light source group 421 consists of three detection light sources. These three detection light sources are located in different areas compared to the second photodetector 41. The detection light sources and the second photodetector 41 form a detection channel. By averaging the signals from different detection channels, errors are reduced. Preferably, an algorithm has been used to filter out outliers. If a channel shows a significant difference from the other two, the machine is stopped for inspection. Possible causes include inappropriate settings for the gas flow rate, temperature, or pressure, leading to unstable fluctuations in the product concentration. Timely inspection and shutdown are necessary to prevent damage to the chamber.

[0072] In some other embodiments of the present invention, the specific layout of the guide rail network 432, the specific type of nanoporous material, and the number of target light source 42 and photodetector can all be adjusted according to the actual chamber size and detection requirements. As long as the target light source 42 can achieve stable optical alignment with the photodetector at multiple spatial positions and construct a multi-region detection channel in the chamber cross-section direction, it should fall within the protection scope of the present invention.

[0073] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0074] Furthermore, if the embodiments of this invention involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by this invention.

[0075] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the present invention. Furthermore, the present invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A multi-region real-time endpoint detection system for semiconductor chamber cleaning, characterized in that, include: The air circuit unit is equipped with a main air inlet, a first branch, a second branch, and a valve module for opening or closing the first branch or the second branch; A first chamber is connected to the first branch. A first broadband light source and a first multi-channel photodetector are arranged opposite each other on both sides of the first chamber. The multiple channels of the first multi-channel photodetector are respectively configured with filters of different center wavelengths. The second chamber is connected to the second branch. Multiple second photodetectors, multiple target light sources and a displacement platform are arranged opposite each other on both sides of the second chamber. The multiple target light sources are installed on the displacement platform and can move relative to the second photodetectors. The control module is connected to the valve module, the first multi-channel photodetector, the displacement platform, and each of the target light sources. The displacement platform includes a target working position. Any of the target light sources can move on the displacement platform to the target working position and be optically aligned with the second photodetector to form a measurement optical path. Multiple target light sources can cooperate with multiple second photodetectors to form a uniformly distributed multi-area detection channel. The displacement platform includes a base and a guide rail network disposed on the base. The target working position is located on the guide rail network. The guide rail network is composed of multiple linear guide rails connected in an interlaced manner to form multiple displacement paths that allow the target light source to move to the target working position. The target light source is movably disposed on the guide rail network. The target light source is a narrow-band light source group with the same center wavelength, and the narrow-band light source group includes multiple detection light sources uniformly distributed along the direction perpendicular to the base.

2. The multi-region real-time endpoint detection system for semiconductor chamber cleaning according to claim 1, characterized in that, The number of channels in the first multi-channel photodetector is greater than the number of channels in the target light source.

3. The multi-region real-time endpoint detection system for semiconductor chamber cleaning according to claim 1, characterized in that, The gas path unit also includes a gas mixer disposed between the main air inlet and the first branch and the second branch. The gas mixer is provided with a turbulence channel and several nanoporous medium homogenization sections in sequence along the airflow direction.

4. The multi-region real-time endpoint detection system for semiconductor chamber cleaning according to claim 3, characterized in that, The turbulence channel is a serpentine meandering channel, and the inner wall of the turbulence channel is provided with periodic nanosphere texture protrusions, which are used to generate local turbulence in the airflow near the wall region.

5. A multi-region real-time endpoint detection system for semiconductor chamber cleaning according to claim 3, characterized in that, The porous medium homogenization section is a cylindrical nanoporous material filled in the internal cavity of the gas mixer, including silica aerogel, carbon aerogel, or metal-organic nanopores.

6. The multi-region real-time endpoint detection system for semiconductor chamber cleaning according to claim 1, characterized in that, It also includes a second broadband light source disposed in the second chamber and movable on the guide rail network. The second broadband light source can be moved to the target working position. The second broadband light source includes a calibration guide rail and a light source body. The calibration guide rail extends in a direction perpendicular to the base, and the light source body slides in conjunction with the calibration guide rail.

7. A multi-region real-time endpoint detection method for semiconductor chamber cleaning, used in the multi-region real-time endpoint detection system for semiconductor chamber cleaning as described in any one of claims 1-6, characterized in that, Includes the following steps: Control the gas path unit to open the first branch and introduce the process gas to be tested into the first chamber; The first broadband light source is activated, and the optical signals of each channel are simultaneously acquired using the first multi-channel photodetector. Analyze the signal changes in each channel, and identify the target gas type and its corresponding characteristic absorption wavelength in the current process environment based on the preset gas absorption spectrum feature library. The gas path unit is controlled to switch to conduct the second branch. Based on the identified target gas type and characteristic absorption wavelength, a target light source whose emission wavelength matches the characteristic absorption wavelength is selected from multiple target light sources installed on the displacement platform. The displacement platform is controlled to move the selected target light source to the target working position and optically align it with the corresponding second photodetector to form a specific measurement optical path for the target gas. During the process, process gas is introduced into the second chamber, and the concentration change of the target gas is monitored in real time based on the measurement optical path. The process endpoint is determined based on the concentration change trend.

8. The multi-region real-time endpoint detection method for semiconductor chamber cleaning according to claim 7, characterized in that, Before controlling the gas path unit to activate the first branch, a pre-zero point calibration step is included, which includes: The first chamber is calibrated using the first broadband light source; The displacement platform includes a guide rail network, on which a second broadband light source is disposed. The second chamber is calibrated using the movable second broadband light source located on the guide rail network.

9. A multi-region real-time endpoint detection method for semiconductor chamber cleaning according to claim 8, characterized in that, The calibration of the first chamber using the first broadband light source specifically includes the following steps: The gas circuit unit is controlled to introduce calibration gas into the first chamber; The first broadband light source is activated, and the optical signals of each channel are synchronously acquired using the first multi-channel photodetector to obtain the reference signals of each channel of the first chamber corresponding to the first broadband light source.

10. A multi-region real-time endpoint detection method for semiconductor chamber cleaning according to claim 8, characterized in that, The calibration of the second chamber using a movable second broadband light source located on the guide rail network includes: The gas circuit unit is controlled to introduce calibration gas into the second chamber; Control the second broadband light source to move to a target working position; The second broadband light source is moved so that the broadband light emitted by the broadband light source is optically aligned with a plurality of second photodetectors in sequence; At each alignment position, the optical signal of the corresponding second photodetector is acquired to obtain the reference signal of each measurement channel in the second chamber.

Images