A PECVD apparatus cleaning method, system, apparatus and storage medium

Abstract

The present application relates to the technical field of PECVD equipment cleaning, and discloses a PECVD equipment cleaning method, system, device and storage medium, which comprises the following steps: generating free radical control parameters and pressure control parameters based on film layer information; adjusting the gas ratio of a gas supply unit and the plasma source power of a double-remote plasma source unit based on the free radical control parameters, so as to initialize the free radical concentration distribution inside the cavity; controlling the vacuum exhaust unit to perform staged vacuumizing on the cavity based on the pressure control parameters, so as to initialize the pressure field inside the cavity; controlling the double-remote plasma source unit to perform in-situ cleaning on the cavity; after the in-situ cleaning is completed, acquiring the cleaning effect index inside the cavity through a detection unit; if the cleaning effect index shows that the cleaning is up to standard, resetting the internal environment of the cavity and generating a cleaning completion signal; the present application solves the problems of mismatching and incompleteness in the prior art, and improves the PECVD equipment cleaning quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PECVD equipment cleaning, in particular to a PECVD equipment cleaning method, system, device and storage medium. BACKGROUND

[0002] Plasma enhanced chemical vapor deposition (PECVD) equipment is usually used for depositing thin films on substrates such as semiconductor substrates, liquid crystal panels and solar cells (high-efficiency heterojunction solar cells); the PECVD equipment is cleaned in situ without disassembly to remove the deposited silicon film layer;

[0003] However, the existing cleaning method directly uses fixed gas ratio, plasma power and vacuum pumping parameters, without customizing adaptive parameters according to the type and thickness of the film layer to be cleaned, resulting in mismatch between the amount of generated free radicals and the reaction demand of the film layer, and mismatch between the pressure field of the cavity and the demand for free radical transmission, which ultimately causes large differences in cleaning degree in different areas of the cavity, and seriously affects the uniformity and quality stability of the deposited film layer of the subsequent PECVD equipment. SUMMARY

[0004] In order to overcome the shortcomings of the prior art, the purpose of the present application is to provide a PECVD equipment cleaning method, system, device and storage medium; the technical scheme of the present application solves the problems of mismatch and incompleteness in the prior art cleaning by customizing parameters, optimizing the environment, precise cleaning and verification reset, which significantly improves the cleaning quality of the PECVD equipment.

[0005] The first aspect of the present application provides a PECVD equipment cleaning method applied to a PECVD equipment cleaning system, wherein the PECVD equipment cleaning system comprises a control device and a gas supply unit, a double-remote plasma source unit, a vacuum pumping unit and a detection unit electrically connected to the control device; the PECVD equipment cleaning method comprises the following steps:

[0006] Obtaining film layer information of a PECVD cavity to be cleaned, and generating free radical control parameters and pressure control parameters based on the film layer information;

[0007] Adjusting the gas ratio of the gas supply unit and the plasma source power of the double-remote plasma source unit based on the free radical control parameters to initialize the free radical concentration distribution inside the cavity;

[0008] Controlling the vacuum pumping unit to pump the cavity in stages based on the pressure control parameters to initialize the pressure field inside the cavity;

[0009] After the free radical concentration distribution and the pressure field are initialized, controlling the double-remote plasma source unit to clean the cavity in situ;

[0010] After the in-situ cleaning is completed, the cleaning effect index inside the cavity is obtained by the detection unit;

[0011] If the cleaning effect index shows that the cleaning is up to standard, the internal environment of the cavity is reset and a cleaning completion signal is generated.

[0012] Optionally, in the first implementation manner of the first aspect of the present application, the film layer information of the PECVD cavity to be cleaned is obtained, and the free radical regulation parameter and the pressure regulation parameter are generated based on the film layer information, which comprises: obtaining the cavity volume and the film layer information of the PECVD cavity to be cleaned; the film layer information comprises film layer type and film thickness data; the total amount of free radicals required for cleaning is calculated based on the film thickness data to obtain the free radical regulation parameter; and the pressure regulation parameter is generated based on the film layer type and the cavity volume.

[0013] Optionally, in the second implementation manner of the first aspect of the present application, the free radical concentration distribution inside the cavity is initialized by adjusting the gas ratio of the gas supply unit and the plasma source power of the double-remote plasma source unit based on the free radical regulation parameter, which comprises: adjusting the gas ratio of the gas supply unit and the plasma source power of the double-remote plasma source unit based on the free radical regulation parameter; controlling the gas supply unit to supply mixed gas into the cavity, and starting the double-remote plasma source unit to ionize the mixed gas to generate fluorine free radicals; obtaining the fluorine free radical concentration inside the cavity, and adjusting the gas ratio of the gas supply unit or the plasma source power of the double-remote plasma source unit according to the fluorine free radical concentration until the fluorine free radical concentration meets the preset uniformity requirement, so as to complete the initialization of the free radical concentration distribution inside the cavity.

[0014] Optionally, in the third implementation manner of the first aspect of the present application, the PECVD equipment cleaning system further comprises a multi-point pressure detection unit electrically connected with the control device; and the pressure field inside the cavity is initialized by controlling the vacuum exhaust unit to perform staged vacuumizing on the cavity based on the pressure regulation parameter, which comprises: the pressure regulation parameter comprises a first-stage rough vacuumizing target pressure, a second-stage fine vacuumizing target pressure and a pressure uniformity threshold value; the rough vacuumizing valve of the vacuum exhaust unit is opened to perform rough vacuumizing on the cavity until the average pressure of the cavity is reduced to the first-stage rough vacuumizing target pressure; the rough vacuumizing valve of the vacuum exhaust unit is closed and the fine vacuumizing valve is opened to perform fine vacuumizing on the cavity until the average pressure of the cavity is reduced to the second-stage fine vacuumizing target pressure; the real-time pressure of each point of the cavity is obtained by the multi-point pressure detection unit, and the pressure deviation value of the real-time pressure and the second-stage fine vacuumizing target pressure is calculated; it is judged whether the pressure deviation value is less than the pressure uniformity threshold value, and if there is a point whose pressure deviation value is greater than the pressure uniformity threshold value, the opening degree of the fine vacuumizing valve is adjusted to perform fine vacuumizing on the cavity until the pressure deviation value of all points is less than the pressure uniformity threshold value, so as to complete the initialization of the pressure field inside the cavity.

[0015] Optionally, in a fourth implementation form of the first aspect of the present application, after the free radical concentration distribution and the pressure field are initialized, the in-situ cleaning of the interior of the chamber by the dual remote plasma source unit comprises: after the free radical concentration distribution and the pressure field are initialized, the dual remote plasma source unit is controlled to deliver fluorine radicals into the chamber for a preset cleaning time, and the vacuum exhaust unit is controlled to exhaust fluorosilicon gas generated by the reaction between the fluorine radicals and the film layer from the chamber, so as to complete the in-situ cleaning of the interior of the chamber.

[0016] Optionally, in a fifth implementation form of the first aspect of the present application, the obtaining of the cleaning effect index of the interior of the chamber by the detection unit after the in-situ cleaning comprises: the detection unit comprises a cleanliness detection assembly and a gas component detection assembly; the reflectivity data of the inner wall of the chamber is obtained by the cleanliness detection assembly; the fluorosilicon gas concentration data of the exhaust outlet of the vacuum exhaust unit is obtained by the gas component detection assembly; and the cleaning effect index is generated based on the reflectivity data and the fluorosilicon gas concentration data.

[0017] Optionally, in a sixth implementation form of the first aspect of the present application, if the cleaning effect index shows that the cleaning is up to standard, the interior environment of the chamber is reset and a cleaning completion signal is generated, which comprises: the cleaning effect index is compared with a preset up-to-standard threshold to obtain a comparison result; if the comparison result shows that the cleaning is up to standard, the dual remote plasma source unit is stopped, and the vacuum exhaust unit is controlled to perform gas purification treatment and pressure relief treatment on the chamber to reset the interior environment of the chamber; and after the reset of the interior environment of the chamber is completed, the cleaning completion signal is generated.

[0018] The second aspect of the present application provides a PECVD equipment cleaning system, which comprises a control device and a gas supply unit, a dual remote plasma source unit, a vacuum exhaust unit and a detection unit electrically connected to the control device; the control device is used to execute the PECVD equipment cleaning method of any one of the above aspects.

[0019] The third aspect of the present application provides a PECVD equipment cleaning device, which comprises a memory and at least one processor, and the memory stores instructions; at least one processor invokes the instructions in the memory, so that the computer device executes the steps of the PECVD equipment cleaning method of any one of the above aspects.

[0020] The fourth aspect of the present application provides a computer readable storage medium, which stores instructions, and the instructions are executed by a processor to implement the steps of the PECVD equipment cleaning method of any one of the above aspects.

[0021] In the technical solution of the application, the specific information of the film layer to be cleaned is first acquired to customize cleaning parameters, ensuring that the subsequent free radical generation amount, pressure field parameters and film layer reaction requirements are accurately matched; secondly, a uniform free radical concentration environment and a stable pressure field are respectively constructed through targeted parameter adjustment, ensuring that each area of the cavity has sufficient reaction conditions; then, in-situ cleaning is carried out, allowing the uniform free radicals to fully react with the film layer in the stable pressure field; then, the cleaning effect index is acquired through the detection unit, realizing visual verification of the cleaning effect; after ensuring that the cleaning meets the standard, the cavity is restored to a state meeting the subsequent deposition requirements; through the logic of customizing parameters, optimizing the environment, accurate cleaning and verification reset, the technical solution of the application solves the problems of mismatching and incompleteness of the prior art cleaning, and significantly improves the cleaning quality of the PECVD equipment. BRIEF DESCRIPTION OF DRAWINGS

[0022] The above and / or additional aspects and advantages of the present application will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings in which:

[0023] Figure 1 The first flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0024] Figure 2 The second flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0025] Figure 3 The third flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0026] Figure 4 The fourth flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0027] Figure 5 The fifth flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0028] Figure 6 The sixth flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0029] Figure 7 The seventh flowchart of the PECVD equipment cleaning method provided by the embodiment of the application;

[0030] Figure 8 The structure schematic diagram of the PECVD equipment cleaning system provided by the embodiment of the application;

[0031] Figure 9 The structure schematic diagram of the PECVD equipment cleaning system provided by the embodiment of the application; DETAILED DESCRIPTION

[0032] The application provides a PECVD equipment cleaning method, system, device and storage medium, which acquires specific information of a film layer to be cleaned to customize cleaning parameters, ensures accurate matching of subsequent radical generation amount, pressure field parameters and film layer reaction requirements, constructs a uniform radical concentration environment and a stable pressure field through targeted parameter adjustment respectively, ensures that each area of the cavity has sufficient reaction conditions, then carries out in-situ cleaning, lets the uniform radicals fully react with the film layer in the stable pressure field, acquires cleaning effect indexes through a detection unit, realizes visual verification of the cleaning effect, restores the cavity to a state meeting subsequent deposition requirements after ensuring that the cleaning meets the standard, and solves the problems of mismatching and incompleteness of the prior art cleaning through the logic of customized parameters, optimized environment, accurate cleaning and verification reset, and significantly improves the PECVD equipment cleaning quality.

[0033] The terms "first", "second", "third", "fourth" and the like in the description, claims, as well as throughout the tables of embodiments, if any, are used for distinguishing between similar objects and not necessarily for describing a particular sequential or chronological order. It is to be understood that the use of these terms herein is to be construed as interchangeable in order to comfort the embodiments described herein with other embodiments described herein other than the one in which these terms are used. Furthermore, the term "comprising" or "containing" and variations thereof as used herein is to be construed in an inclusive sense as opposed to an exclusive sense, that is to say, in the sense of "including, but not limited to", and the like.

[0034] For the purpose of facilitating understanding, the specific flow of the embodiments of the application is described below, please refer to Figure 1 One embodiment of the PECVD equipment cleaning method in the embodiments of the application includes the following steps:

[0035] The PECVD equipment cleaning system includes a control device and a gas supply unit, a double-remote plasma source unit, a vacuum exhaust unit and a detection unit electrically connected with the control device;

[0036] The PECVD equipment cleaning system further includes a multi-point pressure detection unit electrically connected with the control device;

[0037] The detection unit includes a cleanliness detection assembly and a gas component detection assembly;

[0038] In this embodiment, the PECVD equipment cleaning system specifically includes:

[0039] The control device is the core of the system, responsible for receiving feedback data from each detection component, analyzing film layer information to generate control parameters, issuing control instructions to each execution unit, and storing cleaning process data. It uses a Siemens SIMATIC S7-1515F programmable logic controller, supported by a Siemens ET200SP distributed I / O module as communication equipment, and a Beckhoff CP2215 touch screen as a human-machine interface.

[0040] The gas supply unit includes two Agilent 8553 gas mass flow controllers (one for NF3 gas and the other for Ar gas), a gas mixer for mixing the gases, and three solenoid valves for controlling the flow paths of NF3 gas, Ar gas, and mixed gas, respectively.

[0041] The dual-remote plasma source unit uses two MKS ASTeX AX7670 remote plasma sources, supported by an MKS RF-1250 radio frequency power supply (13.56 MHz, power range 0-1500W, adjustment step 1W). The plasma source outlet is equipped with a quartz conduit, which is wrapped with a heating jacket. The quartz conduit is resistant to high temperatures and fluorine corrosion, preventing the introduction of impurities caused by the reaction of free radicals with the conduit material. The heating jacket ensures that the conduit is free of condensate, ensuring stable transmission of free radicals. The two plasma sources are fixed to the top of the PECVD chamber on both sides by adjustable stainless steel supports, with an angle adjustment range of 90°-120°. The outlet of the conduit is 150mm away from the chamber wall, ensuring that the free radical flow generated by the dual-source converges in the center of the chamber, thereby eliminating the edge attenuation zone of single-source cleaning.

[0042] The vacuum pumping unit includes a vacuum pump, two pneumatic vacuum valves (coarse and fine), and a one-way valve to prevent gas backflow.

[0043] The detection unit includes a cleanliness detection component (Keyence LK-G80 laser reflectometer) and a gas composition detection component (Agilent 7890B gas chromatograph). The laser reflectometer is installed outside the observation window on the side wall of the chamber (50mm away from the wall), and the reflectivity data is obtained by scanning the chamber wall (scanning angle 120°). The gas chromatograph is connected to the outlet of the vacuum pumping unit through a sampling tube to detect the concentration of silicon fluoride gas in real time.

[0044] The multi-point pressure detection unit includes twelve Kistler 4085A piezoresistive pressure sensors. The twelve sensors are arranged in the chamber according to the layout of "two at the top of the chamber (corresponding to the lower part of the dual-plasma source outlet), four on the side wall (uniformly distributed along the circumference), three at the bottom (including the center and edge of the workpiece table), and three at the exhaust port" to capture the pressure distribution inside the chamber comprehensively.

[0045] The control principle of the PECVD equipment cleaning system is as follows:

[0046] The control device receives the film layer information input by the operator through the touch screen, calculates the total amount of free radicals (total amount of free radicals = film thickness x cavity surface area x reaction coefficient) in combination with the film thickness, generates free radical regulation parameters and pressure regulation parameters;

[0047] The control device issues a ratio instruction to the gas supply unit, and the flow controller adjusts the flow of NF3 gas and Ar gas in proportion, and then the mixed gas is input into the double plasma source; the radio frequency power supply is started at a preset power, and the ionized gas generates fluorine free radicals;

[0048] The control device starts the vacuum pump, first opens the rough pumping valve to reduce the cavity pressure to the first stage rough pumping target pressure, and then switches the fine pumping valve to the second stage fine pumping target pressure; the pressure sensor collects data, and if there is a pressure deviation, the control device increases the opening degree of the corresponding area exhaust branch valve until the pressure deviation of all points is less than the pressure uniformity threshold;

[0049] After the control device confirms that the two initialization processes are completed, the power of the double plasma source and the input flow of the mixed gas are maintained, and the fine pumping valve of the vacuum pump is kept open; the fluorine free radicals react with the amorphous silicon film in the cavity to generate silicon fluoride gas, which is pumped out by the vacuum pump in real time;

[0050] After the preset cleaning time ends, the control device closes the plasma source and the mixed gas supply, and inputs inert gas into the cavity; the laser reflectometer detects the reflectivity of the wall surface, and the gas chromatograph detects the concentration of silicon fluoride gas to determine whether the cleaning is qualified; if both are qualified, the control device opens the pressure relief valve to reduce the cavity pressure to atmospheric pressure, and generates a cleaning completion signal; if not, return to the original cleaning stage until the standard is met.

[0051] The PECVD equipment cleaning method comprises the following steps:

[0052] 101, obtaining the film layer information of the PECVD cavity to be cleaned, and generating free radical regulation parameters and pressure regulation parameters based on the film layer information;

[0053] In this embodiment, the detection unit collects information such as film layer type and film thickness, and calculates the total amount of free radicals required for cleaning and the adaptive pressure range in combination with the preset process database, generates free radical regulation parameters including gas ratio and plasma power, and pressure regulation parameters including staged vacuum target pressure.

[0054] 102, adjusting the gas ratio of the gas supply unit and the plasma source power of the double remote plasma source unit based on the free radical regulation parameters to initialize the free radical concentration distribution inside the cavity;

[0055] In this embodiment, the flow ratio of NF3 gas and Ar gas of the gas supply unit and the power of the dual plasma source are adjusted according to the radical regulation parameters, and the radical concentration monitoring is performed, so that the radical concentration difference in each region in the cavity meets the uniformity requirement, to complete the initialization of the radical concentration distribution.

[0056] 103. Control the vacuum exhaust unit to perform staged vacuumizing on the cavity based on the pressure regulation parameters, to initialize the pressure field inside the cavity;

[0057] In this embodiment, the coarse exhaust valve is opened to vacuumize to the first stage target pressure, and then the fine exhaust valve is switched to vacuumize to the second stage target pressure, while the pressure deviation is corrected through multi-point pressure detection, to ensure that the pressure of each point in the cavity meets the uniformity threshold, to complete the initialization of the pressure field inside the cavity.

[0058] 104. After the initialization of the radical concentration distribution and the pressure field is completed, control the dual remote plasma source unit to perform in-situ cleaning on the inside of the cavity;

[0059] In this embodiment, the dual plasma source is maintained to stably output fluorine radicals into the cavity within a preset cleaning duration, and the vacuum exhaust unit is simultaneously opened to exhaust the fluorosilicon gas generated by the reaction, to complete the in-situ cleaning of the cavity.

[0060] 105. After the in-situ cleaning is completed, obtain the cleaning effect index of the inside of the cavity through the detection unit;

[0061] In this embodiment, the reflectivity of the inner wall of the cavity is detected by the cleanliness detection assembly, and the fluorosilicon gas concentration at the gas outlet of the vacuum pump is detected by the gas component detection assembly, and the cleaning effect index is generated according to the inner wall reflectivity and the fluorosilicon gas concentration.

[0062] 106. If the cleaning effect index shows that the cleaning is up to standard, reset the internal environment of the cavity and generate a cleaning completion signal;

[0063] In this embodiment, if the cleaning effect index shows that the cleaning effect index is up to standard, the dual remote plasma source unit is closed, inert gas is introduced into the inside of the cavity through the vacuum exhaust unit, to purify the cavity and complete the pressure relief, reset the internal links of the cavity, and finally generate a cleaning completion signal to represent that the cleaning process is completed.

[0064] In the embodiment of the present application, the specific information of the film layer to be cleaned is first acquired to customize the cleaning parameters, ensuring that the subsequent free radical generation amount and pressure field parameters are accurately matched with the reaction requirements of the film layer; secondly, a uniform free radical concentration environment and a stable pressure field are respectively constructed through targeted parameter adjustment, ensuring that each area of the cavity has sufficient reaction conditions; then, in-situ cleaning is carried out, allowing the uniform free radicals to fully react with the film layer in the stable pressure field; then, the cleaning effect index is acquired through the detection unit to realize the visual verification of the cleaning effect; after ensuring that the cleaning meets the standard, the cavity is restored to a state that meets the subsequent deposition requirements; through the logic of customizing parameters, optimizing the environment, accurate cleaning, and verification resetting, the present application solves the problems of mismatching and incompleteness in the prior art, and significantly improves the cleaning quality of the PECVD equipment.

[0065] Please refer to Figure 2 The two embodiments of the PECVD equipment cleaning method in the embodiment of the present application include:

[0066] 201. Acquire the cavity volume and film layer information of the PECVD cavity to be cleaned; the film layer information includes film layer type and film thickness data;

[0067] In this embodiment, the cavity volume of the PECVD cavity to be cleaned (referring to the effective space volume inside the cavity that can contact with free radicals, excluding the volume occupied by structures such as workpiece table and sensor) is determined through cavity design drawings, equipment technical manual or cavity volume calibration tool (such as vacuum method calibration);

[0068] The film layer type is confirmed by the previous deposition process record of the PECVD equipment, film layer composition detection tool or operator input according to production requirements;

[0069] The film thickness data is acquired by the cleanliness detection assembly in the detection unit: first, select at least three characteristic areas (such as top center, middle of side wall and bottom edge) on the cavity wall for multi-point scanning, calculate the film thickness of each area based on the calibration relationship of "film layer reflectivity / polarization characteristics-film thickness", and take the average value as the final film thickness data, ensuring that the film thickness data covers the key areas of the cavity and fits the actual deposition situation.

[0070] 202. Calculate the total amount of free radicals required for cleaning based on the film thickness data to obtain the free radical regulation parameters;

[0071] In this embodiment, the total amount of free radicals required for cleaning is calculated through "film layer reaction relationship + free radical utilization rate correction", specifically as follows:

[0072] 1. First, determine the reaction equation and stoichiometric ratio of the film layer and the target free radical, according to the type of the film layer to be cleaned, determine the reaction equation of the film layer and fluorine free radical, and based on the stoichiometric relationship, determine the number of moles required for 1 mol of film layer to completely react ;

[0073] 2. Calculate the total amount of matter of the film layer to be cleaned on the wall of the cavity, first obtain the total surface area S of the cavity inner wall covered by the film layer, the thickness h of the film layer (film thickness data), determine the density p of the film layer (determined by the type of film layer and deposition process), and the molar mass M (calculated according to the chemical composition and stoichiometric ratio of the film layer); based on the formula: total amount of matter n = (S x h x p) / M, the total amount of matter n1 of the film layer can be calculated;

[0074] 3. Calculate the total amount of matter required for cleaning the film layer: n2 = n1 x , m is the theoretical total amount of moles required for complete cleaning of the film layer;

[0075] 4. Introduce free radical utilization rate correction: considering the loss of fluorine free radicals generated by the double remote plasma source, such as combination and non-participation in reaction; therefore, the total amount of fluorine free radicals required n3 = n2 x fluorine free radical utilization rate ;

[0076] 5. Derive the free radical regulation parameter, which includes the mixing ratio of NF3 gas and Ar gas, and the power of the double remote plasma source, and the derivation logic is as follows:

[0077] NF3 gas is the source of fluorine free radicals, based on the NF3 gas ionization efficiency β of the plasma source (determined by the performance parameters provided by the plasma source manufacturer or experimental calibration), and the preset cleaning time t, the NF3 gas flow Q = n3 / (β x t) can be obtained;

[0078] Ar gas is a carrier for dilution and stabilization of gas flow, and the mixing ratio of NF3 gas and Ar gas needs to be set according to the reactivity of the film layer and the stable operation demand of the plasma source, generally 1:1;

[0079] The power P of the double remote plasma source: based on the fitting curve of the power of the plasma source and the generation amount of fluorine free radicals, combined with the total amount of fluorine free radicals n3 and the preset cleaning time t, the total power of the double remote plasma source can be determined, and then the power of a single plasma source can be obtained according to the uniform distribution of the double source.

[0080] 203, generate pressure regulation parameters based on the type of film layer and the volume of the cavity;

[0081] In this embodiment, the pressure regulation parameters include the first stage rough pumping target pressure P1, the second stage fine pumping target pressure P2, and the pressure uniformity threshold AP:

[0082] Determine the second stage fine pumping target pressure P2 (core working pressure): in the main reaction stage of cleaning, the reaction rate increases with the increase of pressure, but too high pressure will cause the product to be blocked, and too low pressure will reduce the probability of free radical collision reaction; therefore, based on the reaction activity corresponding to the second stage fine pumping target pressure P2 membrane layer type and the cavity volume; the optimal pressure range can be determined by testing the cleaning rate and residual rate of the membrane layer under different pressures, and the middle value of the optimal range is taken as the second stage fine pumping target pressure P2;

[0083] Determine the first stage rough pumping target pressure P1: the target of the rough pumping stage is to quickly reduce the cavity pressure to the range close to the second stage fine pumping target pressure P2, to lay the foundation for the fine pumping stage, and at the same time avoid the film layer from falling off due to sudden pressure drop; therefore, the upper limit of the pressure interval with stable and high pumping speed is selected as the first stage rough pumping target pressure P1 (which can be obtained through the vacuum pump design file), to ensure that the rough pumping stage is completed quickly with high pumping speed, and the vacuum pumping time is shortened;

[0084] Determine the pressure uniformity threshold ΔP: the calibration of the pressure uniformity threshold ΔP ensures that the pressure deviation of each region of the cavity at the second stage fine pumping target pressure P2 (cleaning core working pressure) does not affect the uniformity of free radical diffusion; after the cavity pressure is stabilized at the second stage fine pumping target pressure P2, the gas supply unit is controlled to introduce mixed gas according to the free radical control parameters, and the emission spectrometer is used to detect the free radical concentration in real time; at this time, the dynamic balance of gas inlet and exhaust is maintained by the vacuum exhaust unit (the cavity pressure is stabilized at the second stage fine pumping target pressure P2), until the difference between the fluorine free radical concentrations in each region is ≤2%, which is considered to be stable; after the free radical concentration is stable, the initial pressure values of the twelve pressure sensors are recorded; the fine pumping valve opening is adjusted to produce different pressure deviations, and the fluorine free radical concentration difference in each region is detected by the emission spectrometer at the same time: when the pressure deviation of each point from the second stage fine pumping target pressure P2 is ≤ΔP, if the free radical concentration difference in each region is ≤the preset allowable value (5%), and the corresponding relationship is consistent for three times, then ΔP at this time is determined as the pressure uniformity threshold.

[0085] Please refer to Figure 3 The three embodiments of the PECVD equipment cleaning method in the embodiment of the application include:

[0086] 301, adjust the gas ratio of the gas supply unit and the plasma source power of the double-remote plasma source unit based on the free radical control parameters;

[0087] In this embodiment, the control device first calls the generated free radical regulation parameter, and disassembles the parameter into executable instructions of the gas supply unit and the double-remote plasma source unit; for the gas supply unit, the control device issues a flow adjustment instruction to the built-in gas mass flow controller, sets the flow threshold values of NF3 gas and Ar gas according to the mixing ratio in the free radical regulation parameter, adjusts the valve opening degree of the corresponding gas passage, and ensures that the actual flow ratio of the two gases is consistent with the ratio in the free radical regulation parameter; for the double-remote plasma source unit, the control device issues a power adjustment instruction to the radio frequency power supply, sets the output power threshold of the radio frequency power supply according to the single-source target power in the free radical regulation parameter, and ensures that the actual output power of each plasma source in the double-remote plasma source unit is stable within the target power range, thereby providing accurate initial conditions for subsequent mixed gas ionization and fluorine radical generation.

[0088] 302、control the gas supply unit to supply mixed gas to the inside of the cavity, and start the double-remote plasma source unit to ionize the mixed gas to generate fluorine radicals;

[0089] In this embodiment, the control device first confirms that the flow adjustment of the gas supply unit and the power adjustment of the double-remote plasma source unit have reached the requirements of the free radical regulation parameter, and then issues a gas delivery instruction to the gas supply unit to control the opening of the gas passage valves of NF3 gas and Ar gas, so that the two gases enter the gas mixer at the set flow rate; the mixer fully stirs the two gases to ensure uniform mixing, and then delivers them to the gas inlet of the double-remote plasma source unit through the connecting pipeline; at the same time, the control device issues an ionization start instruction to the double-remote plasma source unit, and the radio frequency power supply outputs a high-frequency electric field at the set power to ionize the mixed gas entering the plasma source cavity to generate fluorine radicals with high reactivity;

[0090] During the mixed gas delivery and ionization process, the control device receives the flow feedback signal of the gas supply unit and the ionization state feedback signal (such as whether there is ionization interruption or abnormal discharge) of the double-remote plasma source unit in real time, and if there is flow fluctuation or ionization abnormality, the operation is immediately suspended and an alarm is triggered, and after the fault is eliminated, the above steps are re-executed to ensure stable generation of fluorine radicals.

[0091] 303、obtain the fluorine radical concentration inside the cavity, and adjust the gas ratio of the gas supply unit or the plasma source power of the double-remote plasma source unit according to the fluorine radical concentration until the fluorine radical concentration meets the preset uniformity requirement, to complete the initialization of the free radical concentration distribution inside the cavity;

[0092] In this embodiment, the control device activates the component (emission spectrometer) in the detection unit used to monitor the concentration of fluorine free radicals. This component collects fluorine free radical concentration data from at least three characteristic regions inside the cavity (such as the cavity center and the two edges near the dual plasma sources) through a detection window reserved in the cavity, and calculates the actual value of the fluorine free radical concentration in each region. The control device compares the actual concentration value of each region with a preset uniformity requirement (concentration difference between regions ≤ 5%). If the concentration difference in all regions meets the requirement, it is determined that the initialization of the free radical concentration distribution inside the cavity is complete; if the concentration difference in any region exceeds the requirement, ... The reasons for the concentration deviation are analyzed as follows: If the plasma source on the corresponding side of the region does not generate enough free radicals, the control device sends a power fine-tuning command to the dual remote plasma source unit to appropriately increase the output power of the plasma source on that side; if the overall free radical generation is too low due to insufficient NF3 gas content in the mixed gas, the control device sends a ratio fine-tuning command to the gas supply unit to appropriately increase the flow rate ratio of NF3 gas; after each adjustment, the fluorine free radical concentration in each region is re-collected and compared until the fluorine free radical concentration in all regions inside the cavity meets the preset uniformity requirements, and finally the initialization of the free radical concentration distribution inside the cavity is completed.

[0093] Please see Figure 4 The four embodiments of the PECVD equipment cleaning method in this invention include:

[0094] 401. The pressure control parameters include the target pressure for the first stage coarse extraction, the target pressure for the second stage fine extraction, and the pressure uniformity threshold.

[0095] In this embodiment, the setting of pressure control parameters needs to be combined with the volume characteristics of the PECVD cavity to be cleaned, the pressure requirements of the film reaction, and the pumping speed capability of the vacuum pumping unit. The target pressure for the first stage of coarse pumping is the transition pressure value that rapidly reduces the initial atmospheric pressure of the cavity to near the core working pressure. The setting logic is to match the high pumping speed range of the coarse pumping valve in the vacuum pumping unit (to ensure that the vacuuming time is shortened with high efficiency during the coarse pumping stage). The target pressure for the second stage of fine pumping is the core working pressure during in-situ cleaning. It needs to be determined based on the reaction rate characteristics of the film and fluorine free radicals (too high pressure will easily lead to poor discharge of reaction products, and too low pressure will reduce the probability of free radical collision reaction) and the pumping stability corresponding to the cavity volume. The pressure uniformity threshold is the standard for measuring the pressure consistency of each area of ​​the cavity. The setting basis is to ensure that the pressure deviation will not affect the uniform diffusion of fluorine free radicals in the cavity (that is, when the pressure deviation at each point is less than the threshold, the free radical distribution uniformity can meet the cleaning requirements). The three together constitute the control benchmark for the initialization of the pressure field.

[0096] 402. Open the coarse evacuation valve of the vacuum pumping unit to perform coarse evacuation of the cavity until the average pressure of the cavity drops to the target pressure of the first stage coarse evacuation.

[0097] In this embodiment, the control device first issues a rough pumping start instruction to the vacuum pumping unit, opens the vacuum pump and the matched rough pumping valve (the rough pumping valve has a large diameter and is suitable for high flow pumping), and performs rough pumping on the PECVD chamber. During the process, the control device collects chamber pressure data in real time through the pressure monitoring module built in the vacuum pumping unit (or the main pressure sensor connected to the chamber), calculates the average chamber pressure every 10 seconds, compares the average pressure calculated in real time with the first-stage rough pumping target pressure, and keeps the rough pumping valve open if the average pressure is higher than the target pressure. If the average pressure drops to the first-stage rough pumping target pressure and remains stable for 30 seconds, the control device determines that the rough pumping stage is completed and prepares for switching to the fine pumping stage.

[0098] 403、Close the rough pumping valve of the vacuum pumping unit and open the fine pumping valve to perform fine pumping on the chamber until the average pressure of the chamber drops to the second-stage fine pumping target pressure.

[0099] In this embodiment, after confirming that the rough pumping stage is completed, the control device first issues a rough pumping valve closing instruction to the vacuum pumping unit, and then issues a fine pumping valve opening instruction after the rough pumping valve is completely closed (the fine pumping valve has a small diameter and is suitable for fine pumping under low pressure). During the fine pumping process, the control device tracks the average pressure change of the chamber in real time through the multi-point pressure detection unit. When the average pressure in the chamber drops to the second-stage fine pumping target pressure and remains stable for 60 seconds, the control device determines that the fine pumping stage is completed, and the overall pressure of the chamber has reached the core working pressure range of the in-situ cleaning.

[0100] 404、Obtain the real-time pressure of each point of the chamber through the multi-point pressure detection unit, and calculate the pressure deviation value between the real-time pressure and the second-stage fine pumping target pressure.

[0101] In this embodiment, after the fine pumping stage is completed, the multi-point pressure detection unit is started to synchronously collect real-time pressure data of all points. After the collection is completed, the pressure deviation value of each sensor point is calculated one by one based on the calculation formula “single-point pressure deviation value = real-time pressure of the point - second-stage fine pumping target pressure”, so as to comprehensively grasp the pressure distribution of each region of the chamber.

[0102] 405、Determine whether the pressure deviation value is less than the pressure uniformity threshold value. If there is a point pressure deviation value greater than the pressure uniformity threshold value, adjust the opening degree of the fine pumping valve to perform fine pumping on the chamber until the pressure deviation value of all points is less than the pressure uniformity threshold value, so as to complete the initialization of the internal pressure field of the chamber.

[0103] In this embodiment, the pressure deviation values of each point calculated in step 404 are compared with the preset pressure uniformity threshold one by one: if the deviation values of all points are less than the pressure uniformity threshold, it indicates that the pressure distribution of each region of the cavity is uniform, which meets the requirements of in-situ cleaning on the pressure field, and the control device determines that the initialization of the pressure field inside the cavity is completed; if there is at least one point whose deviation value is greater than the pressure uniformity threshold, the control device issues a fine valve opening adjustment instruction to the vacuum pumping unit, and adjusts the fine valve opening according to the amplitude of the deviation value; after each adjustment, the control device restarts the multi-point pressure detection unit to collect pressure data of each point until the pressure deviation values of all points are less than the pressure uniformity threshold, and finally completes the initialization of the pressure field inside the cavity.

[0104] Referring to Figure 5 The five embodiments of the PECVD equipment cleaning method in the embodiment of the application include:

[0105] 501、After the initialization of the free radical concentration distribution and the pressure field is completed, the control device controls the double-remote plasma source unit to transport fluorine free radicals into the cavity within a preset cleaning time, and controls the vacuum pumping unit to pump out the fluorosilicon gas generated by the reaction of the fluorine free radicals with the film layer from the cavity, so as to complete the in-situ cleaning inside the cavity;

[0106] In this embodiment, the control device first confirms that the two initializations meet the preset conditions (the concentration difference of free radicals in each region is less than or equal to the uniformity requirement, and the pressure deviation of each point is less than or equal to the pressure uniformity threshold), and then starts the in-situ cleaning process; for the double-remote plasma source unit, the control device issues a continuous operation instruction according to the preset cleaning time, maintains the power output set according to the free radical control parameter, continuously ionizes the mixed gas supplied by the gas supply unit into fluorine free radicals, and stably transports the fluorine free radicals into the cavity through the quartz pipe; the symmetrical layout of the double sources enables the fluorine free radicals to cover the entire cavity, avoiding the problem of insufficient edge free radicals caused by a single source; at the same time, the control device controls the vacuum pumping unit to keep the fine valve open, maintains the pumping speed according to the target pressure set by the pressure control parameter, and ensures that the fluorosilicon gas generated by the reaction of the fluorine free radicals with the film layer in the cavity can be pumped out in real time: on the one hand, it avoids the accumulation of fluorosilicon gas in the cavity, which affects the reactivity of the free radicals, and on the other hand, it prevents the re-deposition of the reaction products on the cavity wall, causing secondary pollution; when the running time reaches the preset cleaning time, the control device determines that the in-situ cleaning inside the cavity is completed.

[0107] Referring to Figure 6 The six embodiments of the PECVD equipment cleaning method in the embodiment of the application include:

[0108] 601、Obtain reflectivity data of the inner wall of the cavity through the cleanliness detection assembly;

[0109] In this embodiment, a laser reflectometer is selected as the cleanliness detection component. Its installation position covers the key areas of the PECVD cavity inner wall (top center, side wall middle, bottom workpiece stage perimeter, and corresponding areas of cavity dead corners, ensuring that the detection data can reflect the cleanliness of the entire area). After the in-situ cleaning is completed, the control device sends a data acquisition command to the cleanliness detection component. The component emits a detection beam of a specific wavelength (650nm red light, chosen because the reflectivity of the residual film layer and the clean wall surface is significantly different, facilitating accurate differentiation). After the detection beam illuminates the target area on the inner wall of the cavity, part of the light is reflected back to the receiving module of the component. The receiving module converts the reflected light signal into an electrical signal and transmits it to the control device. The control device calculates the reflectivity data of each detection area based on the reflected light signal.

[0110] 602. Obtain the concentration data of silicon fluoride gas at the exhaust outlet of the vacuum pumping unit through the gas composition detection component;

[0111] In this embodiment, a gas chromatograph is used as the gas component detection component. Its sampling port is connected to the exhaust outlet of the vacuum pumping unit through a corrosion-resistant pipe (this location is chosen because silicon fluoride is the only gaseous product of the reaction between the film layer and fluorine free radicals, and the concentration at the exhaust outlet can directly reflect whether the reaction is complete). After the in-situ cleaning is completed, the control device first controls the vacuum pumping unit to maintain a fine pumping state for 3-5 minutes (to ensure that the residual silicon fluoride gas in the chamber is fully discharged to the sampling port), and then issues a concentration detection command to the gas component detection component. The sampling pump of the gas component detection component draws the gas sample from the exhaust outlet, and uses the characteristic absorption characteristics of silicon fluoride gas in the 10.5μm infrared band to convert the gas concentration into the corresponding electrical signal intensity. The control device then calculates the real-time concentration data of silicon fluoride gas at the exhaust outlet based on the electrical signal intensity.

[0112] 603. Generate cleaning effect indicators based on reflectivity data and silicon fluoride gas concentration data.

[0113] Please see Figure 7 The seven embodiments of the PECVD equipment cleaning method in this invention include:

[0114] 701. Compare the cleaning effect indicators with the preset compliance thresholds to obtain the comparison results;

[0115] In this embodiment, the preset cleaning standards are as follows: when the reflectivity of each area of ​​the inner wall of the cavity is ≥ the preset reflectivity threshold (85%) and the concentration of silicon fluoride gas is ≤ the preset concentration threshold (1ppm), the cleaning is deemed to be qualified; when both data meet the standards, the cleaning is deemed to be qualified; if any one of them fails to meet the standards, the cleaning is deemed to be unqualified.

[0116] 702、If the comparison result shows that the cleaning is up to standard, stop the operation of the dual remote plasma source unit, and control the vacuum exhaust unit to perform gas purification treatment and pressure relief treatment on the cavity to reset the internal environment of the cavity;

[0117] In this embodiment, after confirming that the comparison result is up to standard, first, a stop command is issued to the dual remote plasma source unit, the radio frequency power supply is turned off, and the generation of fluorine radicals is stopped to avoid unnecessary corrosion of the cavity wall by excess radicals;

[0118] Subsequently, the internal environment reset process of the cavity is started:

[0119] The first step is gas purification treatment. The control device issues an instruction to the gas supply unit to stop NF3 gas delivery and only input inert gas Ar gas. At the same time, the vacuum exhaust unit is controlled to keep the fine exhaust valve open, and the inert gas is used to displace and exhaust the fluorine radicals and silicon fluoride gas remaining in the cavity (i.e., Purge treatment). The Purge duration is set to 5-8 min to ensure that the concentration of harmful gases in the cavity is reduced to a safe range (fluorine radical concentration ≤0.1 ppm).

[0120] The second step is pressure relief treatment. After the gas purification treatment is completed, the control device issues a pressure relief instruction to the vacuum exhaust unit to close the fine exhaust valve and open the pressure relief valve of the cavity, so that the internal pressure of the cavity slowly rises from vacuum to atmospheric pressure. During the pressure relief process, the control device monitors the cavity pressure in real time through the multi-point pressure detection unit. When the pressure rises to the same as the external atmospheric pressure, the pressure relief valve and the inert gas supply are closed, the internal environment reset of the cavity is completed, and the reset cavity environment meets the initial conditions (clean, no harmful residues, pressure balanced with the outside) for subsequent PECVD film deposition.

[0121] 703、After the internal environment of the cavity is reset, a cleaning completion signal is generated;

[0122] In this embodiment, the control device confirms that the internal environment of the cavity is reset by the following methods: first, through the flow feedback signal of the gas supply unit, it is confirmed that the inert gas has stopped being delivered; second, through the pressure data of the multi-point pressure detection unit, it is confirmed that the cavity pressure has stabilized at atmospheric pressure; third, through the gas component detection assembly of the detection unit, the cavity internal gas sample is collected again to confirm the fluorine radical concentration; when the above conditions are all met, the control device determines that the internal environment of the cavity is reset, integrates the key data of this cleaning (such as film layer information, cleaning duration, control parameters, cleaning effect index, reset duration) to generate a cleaning completion signal, which can be displayed through the human-machine interface (touch screen) of the control device to allow the operator to intuitively confirm the cleaning result.

[0123] The PECVD equipment cleaning method in the embodiments of the present application is described above, and the PECVD equipment cleaning system in the embodiments of the present application is described below. Please refer to Figure 8 An embodiment of the PECVD equipment cleaning system in the embodiments of the present application comprises:

[0124] The PECVD equipment cleaning system comprises a control device 801, and a gas supply unit 802, a double-remote plasma source unit 803, a vacuum exhaust unit 804 and a detection unit 805 electrically connected with the control device 801.

[0125] The PECVD equipment cleaning system further comprises a multi-point pressure detection unit 806 electrically connected with the control device 801.

[0126] The detection unit comprises a cleanliness detection assembly 8051 and a gas composition detection assembly 8052.

[0127] Figure 9 The PECVD equipment cleaning device 900 provided in the embodiments of the present application can have great differences due to different configurations or performances, and can comprise one or more than one central processing unit (CPU) 910 (for example, one or more than one processor) and a memory 920, and one or more than one storage medium 930 (for example, one or more than one mass storage device) storing an application program 933 or data 932. The memory 920 and the storage medium 930 can be temporary storage or persistent storage. The program stored in the storage medium 930 can comprise one or more than one module (not shown in the figure), and each module can comprise a series of instruction operations in the PECVD equipment cleaning device 900. Further, the processor 910 can be configured to communicate with the storage medium 930, execute the series of instruction operations in the storage medium 930 on the PECVD equipment cleaning device 900, so as to realize the steps of the PECVD equipment cleaning method provided by the above-mentioned method embodiments.

[0128] The PECVD equipment cleaning device 900 can further comprise one or more than one power supply 940, one or more than one wired or wireless network interface 950, one or more than one input and output interface 960, and / or one or more than one operating system 931, such as Windows Serve, Mac OS X, Unix, Linux, FreeBSD, etc. Those skilled in the art can understand that, Figure 9 The structure of the PECVD equipment cleaning device shown in the figure does not constitute a limitation on the PECVD equipment cleaning device, and can comprise more or fewer components than shown in the figure, or combine certain components, or different component arrangements.

[0129] The application also provides a computer readable storage medium, which can be a non-volatile computer readable storage medium or a volatile computer readable storage medium, and the computer readable storage medium stores instructions, and the instructions make a computer execute the steps of the PECVD device cleaning method when the instructions are run on the computer.

[0130] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the above-described system or device, unit can refer to the corresponding process in the foregoing method embodiments, which will not be described here.

[0131] The integrated unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer readable storage medium. Based on such understanding, the technical solutions of the application essentially or the part of the prior art that makes a contribution or the whole or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a plurality of instructions for making a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the method described in each embodiment of the application. The foregoing storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0132] Finally, it should be noted that: the above only for the preferred examples of the application, and not for limiting the application, although the application is described in detail with reference to the foregoing embodiments, for those skilled in the art, it still can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for some technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the application shall be included in the protection scope of the application.

Claims

1. A method of cleaning a PECVD apparatus, characterized in that, The application is applied to a PECVD equipment cleaning system, which comprises a control device and a gas supply unit, a double-remote plasma source unit, a vacuum exhaust unit and a detection unit electrically connected with the control device; the PECVD equipment cleaning method comprises the following steps: obtaining film layer information of a PECVD cavity to be cleaned, and generating radical regulation parameters and pressure regulation parameters based on the film layer information; the obtaining film layer information of a PECVD cavity to be cleaned, and generating radical regulation parameters and pressure regulation parameters based on the film layer information comprises: obtaining cavity volume and film layer information of a PECVD cavity to be cleaned; the film layer information comprises film layer type and film thickness data; calculating total amount of radicals required for cleaning based on the film thickness data to obtain radical regulation parameters; generating pressure regulation parameters based on the film layer type and the cavity volume; the calculating total amount of radicals required for cleaning based on the film thickness data to obtain radical regulation parameters comprises: determining moles required for complete reaction of the film layer; calculating total amount of substance of the film layer based on total surface area of the cavity inner wall covered by the film layer, density of the film layer, molar mass and film thickness data; calculating theoretical total moles based on the moles required for complete reaction of the film layer and the total amount of substance of the film layer; calculating actual total amount of fluorine radicals required based on the theoretical total moles and fluorine radical utilization rate; deriving radical regulation parameters based on the actual total amount of fluorine radicals required, the radical regulation parameters comprising mixed ratio of NF3 gas and Ar gas and double-remote plasma source power; adjusting gas ratio of the gas supply unit and plasma source power of the double-remote plasma source unit based on the radical regulation parameters to initialize radical concentration distribution inside the cavity; controlling the vacuum exhaust unit to perform staged vacuumization on the cavity based on the pressure regulation parameters to initialize pressure field inside the cavity; after the radical concentration distribution and the pressure field are initialized, controlling the double-remote plasma source unit to perform in-situ cleaning on the cavity; after the in-situ cleaning is completed, obtaining cleaning effect index inside the cavity through the detection unit; if the cleaning effect index shows that the cleaning is up to standard, resetting the cavity internal environment and generating a cleaning completion signal.

2. The PECVD apparatus cleaning method of claim 1, wherein, the adjusting gas ratio of the gas supply unit and plasma source power of the double-remote plasma source unit based on the radical regulation parameters to initialize radical concentration distribution inside the cavity comprises: adjusting gas ratio of the gas supply unit and plasma source power of the double-remote plasma source unit based on the radical regulation parameters; controlling the gas supply unit to supply mixed gas to the cavity, and starting the double-remote plasma source unit to ionize the mixed gas to generate fluorine radicals; obtaining fluorine radical concentration inside the cavity, and adjusting gas ratio of the gas supply unit or plasma source power of the double-remote plasma source unit according to the fluorine radical concentration until the fluorine radical concentration meets preset uniformity requirements, so as to complete initialization of the radical concentration distribution inside the cavity.

3. The PECVD apparatus cleaning method of claim 1, wherein, The PECVD equipment cleaning system further comprises a multi-point pressure detection unit electrically connected with the control device; the vacuum pumping unit is controlled based on pressure regulation parameters to perform staged vacuum pumping on the cavity to initialize the pressure field inside the cavity, including: The pressure regulation parameters include a first-stage rough pumping target pressure, a second-stage fine pumping target pressure, and a pressure uniformity threshold value; A rough pumping valve of the vacuum pumping unit is opened to perform rough vacuum pumping on the cavity until the average pressure of the cavity decreases to the first-stage rough pumping target pressure; The rough pumping valve of the vacuum pumping unit is closed and a fine pumping valve is opened to perform fine vacuum pumping on the cavity until the average pressure of the cavity decreases to the second-stage fine pumping target pressure; Real-time pressures of each point of the cavity are obtained by the multi-point pressure detection unit, and a pressure deviation value of the real-time pressure and the second-stage fine pumping target pressure is calculated; It is judged whether the pressure deviation value is less than the pressure uniformity threshold value, and if there is a point whose pressure deviation value is greater than the pressure uniformity threshold value, the opening degree of the fine pumping valve is adjusted to perform fine vacuum pumping on the cavity until the pressure deviation values of all points are less than the pressure uniformity threshold value, so as to complete the initialization of the pressure field inside the cavity.

4. The PECVD apparatus cleaning method of claim 1, wherein, After the initialization of the radical concentration distribution and the pressure field is completed, the double-remote plasma source unit is controlled to perform in-situ cleaning inside the cavity, including: After the initialization of the radical concentration distribution and the pressure field is completed, the double-remote plasma source unit is controlled to deliver fluorine radicals into the cavity within a preset cleaning time, and the vacuum pumping unit is controlled to discharge fluorosilicon gas generated by the reaction between the fluorine radicals and the film layer from the cavity, so as to complete the in-situ cleaning inside the cavity.

5. The PECVD apparatus cleaning method of claim 1, wherein, After the in-situ cleaning is completed, the cleaning effect index inside the cavity is obtained by the detection unit, including: The detection unit includes a cleanliness detection assembly and a gas component detection assembly; Reflectivity data of the inner wall of the cavity are obtained by the cleanliness detection assembly; Fluorosilicon gas concentration data of the exhaust outlet of the vacuum pumping unit are obtained by the gas component detection assembly; The cleaning effect index is generated based on the reflectivity data and the fluorosilicon gas concentration data.

6. The PECVD apparatus cleaning method of claim 1, wherein, If the cleaning effect index shows that the cleaning is up to standard, the internal environment of the cavity is reset and a cleaning completion signal is generated, including: The cleaning effect index is compared with a preset standard threshold value to obtain a comparison result; If the comparison result shows that the cleaning is up to standard, the double-remote plasma source unit is stopped, and the vacuum pumping unit is controlled to perform gas purification treatment and pressure relief treatment on the cavity to reset the internal environment of the cavity; After the internal environment of the cavity is reset, the cleaning completion signal is generated.

7. A PECVD apparatus cleaning system, characterized by, The PECVD equipment cleaning system comprises a control device and a gas supply unit, a double-remote plasma source unit, a vacuum pumping unit, and a detection unit electrically connected with the control device; the control device is used to execute the PECVD equipment cleaning method according to any one of claims 1-6.

8. A PECVD apparatus cleaning apparatus characterized by, The PECVD equipment cleaning system comprises a memory and at least one processor, and the memory stores instructions; The at least one processor invokes the instructions in the memory to cause the PECVD apparatus cleaning apparatus to perform the steps of the PECVD apparatus cleaning method of any of claims 1-6.

9. A computer-readable storage medium having stored thereon instructions, the computer-readable storage medium comprising: The instructions, when executed by a processor, implement the steps of the PECVD apparatus cleaning method of any of claims 1-6.

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