Method and apparatus for monitoring leak rate of a reaction chamber, and semiconductor processing apparatus

Abstract

To solve the problem that the prior art cannot monitor the leakage rate of a reaction chamber in real time and accurately, the present application provides a reaction chamber leakage rate monitoring method, device and semiconductor process equipment. The reaction chamber leakage rate monitoring method comprises: in a continuous wafer processing process, real-time acquisition of pressure valve opening degree and low radio frequency power peak-to-peak voltage of each wafer when the wafer is subjected to a same preset process step in a reaction chamber; determination of a first difference between pressure valve opening degrees corresponding to two adjacent wafers; determination of a second difference between low radio frequency power peak-to-peak voltages corresponding to the two adjacent wafers; and determination of whether the reaction chamber leaks according to the first difference and the second difference. By using the above method, the leakage rate of the reaction chamber can be monitored in real time and accurately.

Description

Technical Field

[0001] This application relates to the field of semiconductor process equipment technology, specifically to a method, apparatus, and semiconductor process equipment for monitoring the leakage rate of a reaction chamber. Background Technology

[0002] In semiconductor manufacturing, the leakage rate of process chambers is a key indicator for assessing the condition of equipment chambers and ensuring stable equipment operation. Currently, production lines mainly monitor chamber leakage rates through daily scheduled inspections. However, this periodic inspection has significant limitations: First, daily inspections cannot cover sudden leakage rate anomalies within the inspection interval, resulting in some products still being damaged due to momentary leakage; second, once the leakage rate exceeds the standard, it often directly causes in-process defects, ultimately leading to the scrapping of the entire wafer, resulting in serious production losses and cost waste.

[0003] Therefore, there is an urgent need for a method that can provide real-time and accurate early warning of leak rate anomalies, so as to intercept problems in time before they occur and ensure production continuity and product yield. Summary of the Invention

[0004] This application provides a method, apparatus, and semiconductor process equipment for monitoring the leakage rate of a reaction chamber in real time and with high accuracy.

[0005] The technical solution of this invention is as follows:

[0006] In a first aspect, this application provides a method for monitoring the leakage rate of a reaction chamber, comprising:

[0007] During continuous wafer processing, the pressure valve opening and low RF power peak-to-peak voltage of each wafer are collected in real time when the same preset process step is performed in the reaction chamber.

[0008] Determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers;

[0009] Determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers;

[0010] Based on the first difference and the second difference, it is determined whether the reaction chamber has leaked.

[0011] In some possible embodiments, the step of determining whether a leak has occurred in the reaction chamber based on the first difference and the second difference includes:

[0012] The first difference is compared with a first preset threshold, and the corresponding second difference is compared with a second preset threshold;

[0013] When the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated.

[0014] The number of times the aforementioned anomaly markers are generated during the processing of a predetermined number of consecutive wafers is counted;

[0015] If the number of determinations is greater than or equal to the preset number of determinations, it is determined that the reaction chamber has leaked; otherwise, it is determined that the reaction chamber has not leaked.

[0016] In some possible embodiments, the step of determining whether a leak has occurred in the reaction chamber based on the first difference and the second difference includes:

[0017] The first difference is compared with a first preset threshold, and the corresponding second difference is compared with a second preset threshold;

[0018] When the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated.

[0019] If the anomaly marker is continuously generated in a series of comparisons of a preset number of adjacent wafers, it is determined that the reaction chamber is leaking; otherwise, it is determined that the reaction chamber is not leaking.

[0020] In some specific embodiments, the first preset threshold is 0.1° and the second preset threshold is 1v.

[0021] In some specific embodiments, the continuously preset number of pieces is 25 pieces, and the preset number of determinations is 2.

[0022] In some specific embodiments, the preset quantity is 2.

[0023] In some possible embodiments, the method further includes:

[0024] When a leak is detected in the reaction chamber, the semiconductor process equipment is triggered to perform a shutdown or alarm operation.

[0025] In some possible embodiments, the preset process step is the main etching process step.

[0026] Secondly, this application also provides a leak rate monitoring device for a reaction chamber, comprising:

[0027] The acquisition module is used to acquire, in real time, the pressure valve opening and low-frequency power peak-to-peak voltage of each wafer as it undergoes the same preset process step in the reaction chamber during continuous wafer processing.

[0028] The first difference determination module is used to determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers;

[0029] The second difference determination module is used to determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers.

[0030] The processing module is used to determine whether a leak has occurred in the reaction chamber based on the first difference and the second difference.

[0031] Thirdly, this application also provides a semiconductor process apparatus, including a reaction chamber and a leak rate monitoring device for the reaction chamber.

[0032] The beneficial effects of this invention are as follows:

[0033] When a leak occurs in the reaction chamber, the inflow of external gas disrupts the pressure balance within the chamber. To maintain the set pressure, the opening of the pressure valve needs to be adjusted in real time. Therefore, changes in the opening of the pressure valve directly reflect the macroscopic gas flow balance within the reaction chamber, with extremely low response delay. Furthermore, changes in gas composition or pressure caused by a leak in the reaction chamber instantly alter the plasma impedance. To maintain a constant low-frequency radio frequency power applied to the electrodes within the reaction chamber, the electrode voltage must jump. In other words, the peak-to-peak voltage of this low-frequency radio frequency power is extremely sensitive to changes in the microscopic gas environment.

[0034] By capturing the synchronous signals of two independent physical effects that are necessarily related when a leak occurs in the reaction chamber, and using the inherent data in the wafer production process for real-time analysis, the pain points of traditional leak detection methods, such as lag, low frequency, and susceptibility to false alarms, are fundamentally solved. This achieves a technological leap from passive periodic sampling to proactive real-time wafer-by-wafer monitoring, thereby improving monitoring accuracy and timeliness. Attached Figure Description

[0035] Figure 1 This is a flowchart illustrating the leakage rate monitoring method for the reaction chamber in the first embodiment of this application;

[0036] Figure 2 This is a flowchart illustrating the leakage rate monitoring method for the reaction chamber in the second embodiment of this application;

[0037] Figure 3 This is a flowchart illustrating the leak rate monitoring method for the reaction chamber in the third embodiment of this application;

[0038] Figure 4 This is a structural block diagram of the leakage rate monitoring device for the reaction chamber in the fourth embodiment of this application. Detailed Implementation

[0039] To make the objectives, advantages, and features of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the drawings are all in a very simplified form and are not drawn to scale, and are only used to facilitate and clarify the explanation of the embodiments of this invention. Furthermore, the structures shown in the drawings are often part of the actual structures. In particular, different figures may emphasize different aspects and may sometimes use different scales.

[0040] As used herein, the singular forms “a,” “an,” and “the” include plural objects unless otherwise expressly indicated. As used herein, the term “or” is generally used to include the meaning of “and / or” unless otherwise expressly indicated. As used herein, the term “a number” is generally used to include the meaning of “at least one” unless otherwise expressly indicated. As used herein, the term “at least two” is generally used to include the meaning of “two or more” unless otherwise expressly indicated. Furthermore, the terms “first,” “second,” and “third” are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as “first,” “second,” or “third” may explicitly or implicitly include one or at least two of that feature.

[0041] Reference Figure 1 The first embodiment of this application provides a method for monitoring the leakage rate of a reaction chamber, comprising:

[0042] S101, during continuous wafer processing, collects in real time the pressure valve opening and low RF power peak-to-peak voltage of each wafer when it performs the same preset process step in the reaction chamber.

[0043] S102, determine the first difference between the opening of the pressure valves corresponding to two adjacent wafers;

[0044] S103, determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers;

[0045] S104, Based on the first difference and the second difference, determine whether the reaction chamber has leaked.

[0046] In the first embodiment of this application, the reaction chamber refers to a reaction chamber capable of providing a low-pressure environment for semiconductor processes such as deposition or etching processes.

[0047] Under normal circumstances, during wafer fabrication, the processing steps, process parameters, and dwell time of each wafer in the same reaction chamber strictly follow the same formula; when each wafer performs the same process, the physical conditions (such as pressure distribution, gas flow rate, plasma impedance, etc.) in the reaction chamber should be highly repetitive.

[0048] In step S101, the continuous wafer processing process refers to the normal production process of processing wafers without interruption according to a predetermined production cycle. Unlike traditional leak detection methods that require interrupting production and conducting special vacuum tests, the first embodiment of this application collects data under completely normal production process conditions, and then uses the collected data for leak monitoring, without having to change or interrupt the process flow for monitoring.

[0049] In the first embodiment of this application, the pressure valve is an Automatic Pressure Control Valve (APC), specifically a throttle valve installed on the vacuum extraction pipeline of the reaction chamber. This pressure valve is controlled by a motor or pneumatic device to regulate the gas pressure within the reaction chamber. The motor or pneumatic device controls the rate at which gas is extracted from the reaction chamber by adjusting the rotation angle (opening degree) of the valve disc, thereby dynamically maintaining the process pressure within the reaction chamber at a set value. When leakage occurs within the reaction chamber (i.e., additional gas enters), the controller will increase the opening angle of the pressure valve to accelerate extraction in order to counteract the pressure rise within the reaction chamber.

[0050] In the first embodiment of this application, the low radio frequency voltage peak-to-peak (Lo_RF_VPP) refers to the peak-to-peak value of the AC voltage corresponding to the low-frequency radio frequency power applied to the internal electrodes of the reaction chamber. The AC power of a specific frequency generated by the radio frequency power supply is transmitted to the internal electrodes of the reaction chamber through a matching network. A voltage probe installed at the electrodes measures the AC waveform of the low-voltage radio frequency signal on the electrodes in real time. The peak-to-peak voltage of this AC waveform is defined as the voltage difference between the highest and lowest points of the AC signal within one cycle, and its value directly characterizes the amplitude intensity of the radio frequency voltage. This peak-to-peak voltage of the AC waveform is the low radio frequency voltage peak-to-peak referred to in the first embodiment of this application.

[0051] The low RF power peak-to-peak voltage directly reflects the impedance characteristics of the plasma load. When a leak occurs in the reaction chamber, causing a change in gas composition or pressure, the plasma impedance will change immediately, resulting in a significant jump in the low RF power peak-to-peak voltage.

[0052] In the first embodiment of this application, the opening degree of the pressure valve is collected in real time by the position sensor built into the pressure valve; the peak-to-peak voltage of the low radio frequency power is obtained by the AC waveform collected by the voltage probe.

[0053] Furthermore, in the first embodiment of this application, data is collected during a period when the preferred parameters of the same preset process step have reached a stable platform, such as any one of the following process steps: main etching step, over-etching step, chamber cleaning step, or thin film growth step in thin film deposition process. Preferably, this preset process step is, for example, the main etching process step, because in the main etching step, the process gas, RF power, and chamber pressure are all at high and stable set values. At this time, the pressure valve opening and the low RF power peak-to-peak voltage are in an active steady state with distinct characteristics and the strongest signal, making them most sensitive to leakage.

[0054] Thus, through the above description, data acquisition can be achieved under completely normal production process conditions.

[0055] In the first embodiment of this application, the first difference in step S102 specifically refers to the absolute value of the difference in the opening degree of the pressure valves corresponding to two adjacent wafers; similarly, the second difference in step S103 specifically refers to the absolute value of the difference in the peak-to-peak voltage of the low-frequency power corresponding to two adjacent wafers. A typical response caused by leakage in the reaction chamber is a change in the pressure valve opening degree towards increasing and a sharp jump in the peak-to-peak voltage of the low-frequency power; although the direction of the jump may be regular, using absolute values ​​can cover all possible abnormal patterns (including rare reverse changes), making monitoring more comprehensive.

[0056] When a leak occurs in the reaction chamber, the inflow of external gas disrupts the pressure balance within the chamber. To maintain the set pressure, the opening of the pressure valve needs to be adjusted in real time. Therefore, changes in the opening of the pressure valve directly reflect the macroscopic gas flow balance within the reaction chamber, with extremely low response delay. Furthermore, changes in gas composition or pressure caused by a leak in the reaction chamber instantly alter the plasma impedance. To maintain a constant low-frequency radio frequency power applied to the electrodes within the reaction chamber, the electrode voltage must jump. In other words, the peak-to-peak voltage of this low-frequency radio frequency power is extremely sensitive to changes in the microscopic gas environment.

[0057] By capturing the synchronous signals of two independent physical effects that are inevitably associated when a reaction chamber leak occurs, and using inherent data from the wafer manufacturing process for real-time analysis, this method fundamentally solves the pain points of traditional leak detection methods, such as lag, low frequency, and susceptibility to false alarms. It represents a technological leap from passive periodic sampling to proactive real-time wafer-by-wafer monitoring, significantly improving monitoring accuracy and timeliness. Before reaction chamber leaks cause physical damage to the product, anomalies are simultaneously compared using the first and second differences to eliminate false alarms caused by single parameters due to equipment noise, normal process fluctuations, or sensor malfunctions. Furthermore, this method collects inherent process parameters from each wafer during processing, without interfering with production.

[0058] In the first embodiment of this application, the method further includes:

[0059] S105, when it is determined that a leak has occurred in the reaction chamber, the semiconductor process equipment is triggered to perform a shutdown or alarm operation.

[0060] In semiconductor process equipment, when a leak is detected in the reaction chamber, an automatic shutdown or alarm is triggered. The core purpose is to build a fail-safe defense system, prioritizing personal safety and environmental protection. This prevents the risk of poisoning, fire, or explosion caused by leaks of toxic or flammable gases. At the same time, it protects high-value wafer products by preventing air pollutants (such as oxygen, water vapor, and particles) from entering the chamber and causing thin film performance failure, chip defects, and mass scrapping. It also protects expensive equipment hardware from damage such as abnormal discharge, component oxidation, and vacuum system overload. Ultimately, through a graded response mechanism (early warning or emergency shutdown), it minimizes safety risks and economic losses, ensuring the high reliability and controllability of the semiconductor manufacturing process.

[0061] Reference Figure 2 The second embodiment of this application provides a method for monitoring the leakage rate of a reaction chamber, comprising:

[0062] S201, during continuous wafer processing, collects in real time the pressure valve opening and low RF power peak-to-peak voltage of each wafer when it performs the same preset process step in the reaction chamber.

[0063] S202, determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers;

[0064] S203, determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers;

[0065] S204, compare the first difference with the first preset threshold, and compare the corresponding second difference with the second preset threshold;

[0066] S205, when the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated;

[0067] S206, Count the number of times the abnormal identifier is generated during the processing of a preset number of wafers in a continuous process;

[0068] S207, if the number of times is greater than or equal to the preset number of determinations, it is determined that the reaction chamber has leaked;

[0069] S208, if the number of times is less than the preset number of determinations, it is determined that no leakage has occurred in the reaction chamber;

[0070] S209, when it is determined that a leak has occurred in the reaction chamber, the semiconductor process equipment is triggered to perform a shutdown or alarm operation.

[0071] The implementation process of steps S201-S203 is the same as that of steps S101-S103 in the first embodiment above, and will not be repeated in this embodiment.

[0072] In step S204, the first preset threshold and the second preset threshold are obtained by modeling based on historical data. The specific implementation of determining the first and second preset thresholds is as follows: extract the final steady-state value of the pressure valve opening and the steady-state value of the low-RF power peak-to-peak voltage corresponding to each wafer under the same process step; perform data cleaning on the extracted massive data to remove known abnormal batches, unstable data before and after maintenance, and invalid data such as sensor communication errors; for each wafer in the historical dataset, calculate the absolute value difference (of the pressure valve opening) and the absolute value difference (of the low-RF power peak-to-peak voltage) between it and the previous wafer under the same step, thereby obtaining the first difference sequence and the second difference sequence. Perform statistical distribution analysis on these two difference sequences to determine the first and second preset thresholds corresponding to leakage in the reaction chamber. Based on actual data analysis, in the second embodiment of this application, the first preset threshold is set to, for example, 0.1°, and the second preset threshold is set to, for example, 1V.

[0073] In step S205, for two adjacent wafers in a single instance, if the first difference is greater than a first preset threshold and the corresponding second difference is greater than a second preset threshold, it could be due to a genuine leak in the reaction chamber, or it could be caused by various occasional, transient interferences. For example: a tiny bubble momentarily passing through the process gas pipeline, causing instantaneous pressure and plasma disturbances; a minor, self-recovering discharge / arc of the RF power supply or matching network; transient electromagnetic interference to the sensor signal; or accidental process fluctuations caused by microscopic inhomogeneities in the wafer itself or the support stage. While these occasional events may cause the first and second differences to simultaneously meet the corresponding abnormal conditions, they are fleeting and do not represent permanent physical damage to the reaction chamber. If a leak in the reaction chamber is assumed to occur simply because the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, it will lead to numerous false alarms and severely disrupt production. For example, in Table 1, for the specific process module 110_1F (where 110 represents 100nm, and 1F represents the process with internal number 1F; in this embodiment, 110_1F represents, for example, the first layer of hard mask etching at 110nm), A_OOS_1P means that if a first difference is greater than a first preset threshold and the corresponding second difference is greater than a second preset threshold, it is considered a reaction chamber leak, which will result in 28 false alarms. However, the actual number of damaged wafers (Suffer wafers) is only 1. It can be seen that if only one first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, it should be regarded as an anomaly that requires special attention, but it cannot be defined as a reaction chamber leak. Otherwise, a large number of interfering alarms will be generated.

[0074]

[0075] Table 1

[0076] In step S206, in the second embodiment of this application, the number of consecutive preset pieces is defined as 25 pieces, which is the commonly used sampling and monitoring quantity in the industry.

[0077] In step S207, the preset number of judgments is set to, for example, 2. Referring back to Table 1, the inventors found through experiments that A_OOS_2of25, meaning the number of times the anomaly marker is generated during the processing of 25 consecutive wafers, will result in 2 false alarms, and the actual number of damaged wafers is only 1. This almost completely eliminates false alarms (from 28 to 2) while maintaining an extremely high detection rate (only 1 wafer is missed), achieving the best balance between reliability and sensitivity. However, if the preset number of judgments is set to 3, meaning the number of times the anomaly marker is generated during the processing of 25 consecutive wafers (A_OOS_3of25), the actual number of damaged wafers is 5. Although no false alarms occur, such a large number of damaged wafers is unacceptable. This indicates that setting the preset number of judgments to 3 is too sluggish; by the time 3 anomalies accumulate, a large number of wafers have already been scrapped while waiting for alarms.

[0078] The method in the second embodiment described above, by imposing stricter limits on each threshold, can more accurately predict leakage in the reaction chamber.

[0079] Reference Figure 3 The third embodiment of this application provides a method for monitoring the leakage rate of a reaction chamber, including:

[0080] S301, during continuous wafer processing, collects in real time the pressure valve opening and low RF power peak-to-peak voltage of each wafer when it performs the same preset process step in the reaction chamber.

[0081] S302, determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers;

[0082] S303, determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers;

[0083] S304, compare the first difference with the first preset threshold, and compare the corresponding second difference with the second preset threshold;

[0084] S305, when the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated;

[0085] S306, if the abnormality marker is continuously generated in a series of comparisons of a preset number of adjacent wafers, it is determined that the reaction chamber has leaked;

[0086] S307, if the number of times is less than the preset number of determinations, it is determined that no leakage has occurred in the reaction chamber;

[0087] S308, when it is determined that a leak has occurred in the reaction chamber, the semiconductor process equipment is triggered to perform a shutdown or alarm operation.

[0088] The implementation process of steps S301-S303 is the same as that of S101-S103 in the first embodiment above. The implementation process of steps S304 and S305 is the same as that of S204 and S205 in the second embodiment above. Therefore, it will not be described again in this embodiment.

[0089] The difference from the second embodiment is that in the third embodiment, the condition for leakage in the reaction chamber is adjusted so that the abnormality indicator is continuously generated in the comparison of a preset number (e.g., 3) of adjacent wafers. This can completely eliminate misidentification caused by occasional or instantaneous interference and improve the accuracy of leakage assessment of the reaction chamber.

[0090] Reference Figure 4 The fourth embodiment of this application also provides a leak rate monitoring device for a reaction chamber, comprising:

[0091] The acquisition module 101 is used to acquire, in real time, the pressure valve opening and low RF power peak-to-peak voltage of each wafer when it is performing the same preset process step in the reaction chamber during continuous wafer processing.

[0092] The first difference determination module 102 is used to determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers;

[0093] The second difference determination module 103 is used to determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers.

[0094] The processing module 104 is used to determine whether the reaction chamber has leaked based on the first difference and the second difference.

[0095] In the fourth embodiment of this application, the pressure valve is an automatic pressure control valve (APC), specifically a throttle valve installed on the vacuum extraction pipeline of the reaction chamber. This pressure valve is controlled by a motor or pneumatic device to regulate the gas pressure within the reaction chamber. The motor or pneumatic device controls the rate at which gas is extracted from the reaction chamber by adjusting the rotation angle (i.e., opening degree) of the pressure valve disc, thereby dynamically maintaining the process pressure within the reaction chamber at a set value. When leakage occurs within the reaction chamber (i.e., additional gas enters), the controller will increase the opening angle of the pressure valve to accelerate gas extraction in order to counteract the pressure rise within the reaction chamber.

[0096] Low Radio Frequency Voltage Peak-to-Peak (Lo_RF_VPP) refers to the peak-to-peak value of the AC voltage corresponding to the low-frequency radio frequency power applied to the electrodes inside the reaction chamber. The AC power of a specific frequency generated by the radio frequency power supply is transmitted to the electrodes inside the reaction chamber through a matching network. A voltage probe installed at the electrodes measures the AC waveform of the low-voltage radio frequency signal on the electrodes in real time. The peak-to-peak voltage of this AC waveform is defined as the voltage difference between the highest and lowest points of the AC signal within one cycle, and its value directly characterizes the amplitude intensity of the radio frequency voltage. This peak-to-peak voltage of the AC waveform is the low radio frequency voltage peak-to-peak value referred to in the first embodiment of this application.

[0097] The low RF power peak-to-peak voltage directly reflects the impedance characteristics of the plasma load. When a leak occurs in the reaction chamber, causing a change in gas composition or pressure, the plasma impedance will change immediately, resulting in a significant jump in the low RF power peak-to-peak voltage.

[0098] The opening degree of the pressure valve is collected in real time by the position sensor built into the pressure valve; the peak-to-peak voltage of the low radio frequency power is obtained by the AC waveform collected by the voltage probe.

[0099] Furthermore, data is collected during the period when the preferred parameters of the same preset process step have reached a stable platform, such as any one of the process steps including the main etching step, the over-etching step, the chamber cleaning step, or the thin film growth step in the thin film deposition process. Optimally, this preset process step is, for example, the main etching process step, because in the main etching step, the process gas, RF power, and chamber pressure are all at high and stable setpoints. At this time, the pressure valve opening and the low RF power peak-to-peak voltage are in an active steady state with distinct characteristics and the strongest signal, making them most sensitive to leakage.

[0100] Thus, through the above description, data acquisition can be achieved under completely normal production process conditions.

[0101] The first difference specifically refers to the absolute value of the difference in pressure valve opening between two adjacent wafers; similarly, the second difference specifically refers to the absolute value of the difference in low-RF power peak-to-peak voltage between two adjacent wafers. A typical response caused by reaction chamber leakage is a change in pressure valve opening towards increasing and a sharp jump in low-RF power peak-to-peak voltage; although the direction of the jump may be regular, using absolute values ​​can cover all possible anomaly patterns (including rare reverse changes), making monitoring more comprehensive.

[0102] When a leak occurs in the reaction chamber, the inflow of external gas disrupts the pressure balance within the chamber. To maintain the set pressure, the opening of the pressure valve needs to be adjusted in real time. Therefore, changes in the opening of the pressure valve directly reflect the macroscopic gas flow balance within the reaction chamber, with extremely low response delay. Furthermore, changes in gas composition or pressure caused by a leak in the reaction chamber instantly alter the plasma impedance. To maintain a constant low-frequency radio frequency power applied to the electrodes within the reaction chamber, the electrode voltage must jump. In other words, the peak-to-peak voltage of this low-frequency radio frequency power is extremely sensitive to changes in the microscopic gas environment.

[0103] By capturing the synchronous signals of two independent physical effects that are inevitably associated when a reaction chamber leak occurs, and using inherent data from the wafer manufacturing process for real-time analysis, this method fundamentally solves the pain points of traditional leak rate detection methods, such as lag, low frequency, and susceptibility to false alarms. It achieves a technological leap from passive periodic sampling to proactive real-time wafer-by-wafer monitoring, thereby improving monitoring accuracy and timeliness. Before a reaction chamber leak causes physical damage to the product, anomalies are simultaneously compared using the first and second differences to eliminate false alarms caused by single parameters due to equipment noise, normal process fluctuations, or sensor malfunctions. Furthermore, this method collects inherent process parameters from each wafer during processing, without interfering with production.

[0104] The processing module 104 performs leak rate monitoring of the reaction chamber based on steps S204-S208 in the second embodiment or steps S304-S307 in the third embodiment.

[0105] The fifth embodiment of this application also provides a semiconductor process apparatus, including a reaction chamber and a leak rate monitoring device for the reaction chamber described in the fourth embodiment above.

[0106] The above description of the embodiments shown in this invention (including the content set forth in the abstract of the specification) is not intended to be an exhaustive enumeration or to limit the invention to the precise forms disclosed herein. Although specific embodiments and examples of the invention have been described herein for illustrative purposes only, various equivalent modifications are possible within the spirit and scope of the invention, as will be recognized and understood by those skilled in the art. As indicated, these modifications can be made to the invention in accordance with the above description of the embodiments described herein, and such modifications will be within the spirit and scope of the invention.

[0107] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to the technical solutions formed by specific combinations of the above-described technical features. It should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in this application. Except for the technical features described in the specification, the remaining technical features are known to those skilled in the art. To highlight the innovative features of this invention, the remaining technical features will not be described further here.

Claims

1. A method for monitoring the leakage rate of a reaction chamber, characterized in that, include: During continuous wafer processing, the pressure valve opening and low RF power peak-to-peak voltage of each wafer are collected in real time when the same preset process step is performed in the reaction chamber. Determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers; Determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers; Based on the first difference and the second difference, determine whether the reaction chamber has leaked; The step of determining whether a leak has occurred in the reaction chamber based on the first difference and the second difference includes: The first difference is compared with a first preset threshold, and the corresponding second difference is compared with a second preset threshold; When the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated. The number of times the aforementioned anomaly markers are generated during the processing of a predetermined number of consecutive wafers is counted; If the number of determinations is greater than or equal to the preset number of determinations, it is determined that the reaction chamber has leaked; otherwise, it is determined that the reaction chamber has not leaked.

2. The leakage rate monitoring method for the reaction chamber according to claim 1, characterized in that, The step of determining whether a leak has occurred in the reaction chamber based on the first difference and the second difference includes: The first difference is compared with a first preset threshold, and the corresponding second difference is compared with a second preset threshold; When the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated. If the anomaly marker is continuously generated in a series of comparisons of a preset number of adjacent wafers, it is determined that the reaction chamber is leaking; otherwise, it is determined that the reaction chamber is not leaking.

3. The leakage rate monitoring method for the reaction chamber according to claim 1, characterized in that, The first preset threshold is 0.1°, and the second preset threshold is 1v.

4. The leakage rate monitoring method for the reaction chamber according to claim 1, characterized in that, The preset number of consecutive pieces is 25 pieces, and the preset number of judgments is 2.

5. The leakage rate monitoring method for the reaction chamber according to claim 2, characterized in that, The preset quantity is 2.

6. The leak rate monitoring method for the reaction chamber according to claim 1, characterized in that, The method further includes: When a leak is detected in the reaction chamber, the semiconductor process equipment is triggered to perform a shutdown or alarm operation.

7. The leak rate monitoring method for the reaction chamber according to claim 1, characterized in that, The preset process steps are the main etching process steps.

8. A leak rate monitoring device for a reaction chamber, characterized in that, include: The acquisition module is used to acquire, in real time, the pressure valve opening and low-frequency power peak-to-peak voltage of each wafer as it undergoes the same preset process step in the reaction chamber during continuous wafer processing. The first difference determination module is used to determine the first difference between the opening degrees of the pressure valves corresponding to two adjacent wafers; The second difference determination module is used to determine the second difference between the low RF power peak-to-peak voltages of two adjacent wafers. The processing module is used to determine whether a leak has occurred in the reaction chamber based on the first difference and the second difference; The step of determining whether a leak has occurred in the reaction chamber based on the first difference and the second difference includes: The first difference is compared with a first preset threshold, and the corresponding second difference is compared with a second preset threshold; When the first difference is greater than the first preset threshold and the corresponding second difference is greater than the second preset threshold, an anomaly identifier is generated. The number of times the aforementioned anomaly markers are generated during the processing of a predetermined number of consecutive wafers is counted; If the number of determinations is greater than or equal to the preset number of determinations, it is determined that the reaction chamber has leaked; otherwise, it is determined that the reaction chamber has not leaked.

9. A semiconductor process apparatus, characterized in that, It includes a reaction chamber and a leak rate monitoring device for the reaction chamber as described in claim 8.

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