Verification method of mass flow controller and chemical vapor deposition machine

Abstract

The invention provides a verification method of a mass flow controller and a chemical vapor deposition machine. The method comprises the following steps: in a gap between two adjacent process treatments, setting a first mass flow controller to be a preset flow, introducing first gas into a vacuum reaction chamber through a first gas pipeline, and measuring the gas pressure change of the reaction chamber to obtain a first pressure change rate; setting a second mass flow controller as a preset flow, introducing a second gas into the vacuum reaction chamber through a second gas pipeline, and measuring the gas pressure change of the reaction chamber to obtain a second pressure change rate; obtaining a detection relation coefficient based on the first pressure change rate and the second pressure change rate; and when the deviation ratio between the detection relation coefficient and a pre-obtained reference relation coefficient is greater than a preset threshold value, determining that the at least one mass flow controller has abnormal deviation. Through the method, the gas flow deviation of the machine can be detected, and the flow control condition of the mass flow controller is fed back, so that the use efficiency of the machine is improved, and the detection cost is reduced.

Description

Technical Field

[0001] The present application relates to the field of semiconductor manufacturing technology, and more specifically to a calibration method for a mass flow controller and a chemical vapor deposition machine. Background Art

[0002] Chemical Vapor Deposition (CVD) is a process in which two or more gaseous or vaporous substances react in the gas phase or at a gas-solid interface to form solid deposits. A CVD machine usually includes a reaction chamber and a gas supply system. The reaction chamber is the main area for chemical reactions and thin film deposition. The gas supply system is used to provide reactive gas or gas mixtures to the reaction chamber. It includes components such as a gas source, a mass flow controller (MFC), and a gas transmission pipeline.

[0003] During the CVD process, the gas flows through the pipeline to the mass flow controller, and then to the distribution plate to enter the reaction chamber to participate in the reaction and perform thin film deposition. Among them, the mass flow controller is an important part of the gas transmission equipment in the thin film deposition technology. It not only has the function of accurately measuring the gas flow, but also can control the gas flow according to the user's settings. During the process, MFC abnormalities will cause the MFC flow detection mechanism to be inaccurate, which will cause the MFC flow control to deviate, affecting the amount of reaction gas entering the reaction chamber. Abnormal gas flow will lead to abnormal film deposition thickness or even product scrapping. Therefore, it is necessary to detect gas flow abnormalities in a timely manner during machine operation.

[0004] In the related art, the machine needs to be shut down to execute the flow detection procedure inside the machine, the detection frequency is low, and the equipment utilization efficiency is reduced, resulting in high detection costs. Summary of the invention

[0005] The present application is proposed in view of the above problems. The present application provides a calibration method for a mass flow controller and a chemical vapor deposition machine, which can detect the gas flow deviation of the machine at any time and provide feedback on the flow control status of the mass flow controller, thereby improving the use efficiency of the machine and reducing the detection cost.

[0006] According to a first aspect of the present application, a calibration method for a mass flow controller is provided, wherein the plurality of mass flow controllers include a first mass flow controller and a second mass flow controller, which are respectively arranged on a first gas pipeline and a second gas pipeline connected to the same reaction chamber; the calibration method includes, in the interval between two adjacent process treatments:

[0007] Setting the first mass flow controller to a preset flow rate, introducing a first gas into the vacuum reaction chamber through the first gas pipeline, and measuring a pressure change in the reaction chamber to obtain a first pressure change rate;

[0008] Setting the second mass flow controller to a preset flow rate, introducing a second gas into the vacuum reaction chamber through the second gas pipeline, and measuring the gas pressure change in the reaction chamber to obtain a second pressure change rate;

[0009] Obtaining a detection relationship coefficient based on the first pressure change rate and the second pressure change rate;

[0010] When the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient is greater than a preset threshold, it is determined that at least one of the first mass flow controller and the second mass flow controller has an abnormal deviation.

[0011] In one embodiment of the present application, the preset flow rate is 40%-60% of the maximum range of the mass flow controller.

[0012] In one embodiment of the present application, the reaction chamber is further connected to a vacuum pump via a valve, and the vacuum pump is used to evacuate the reaction chamber;

[0013] The step of introducing the first gas into the vacuum reaction chamber through the first gas pipeline and measuring the change in the gas pressure of the reaction chamber to obtain the first pressure change rate comprises: opening the valve and the vacuum pump to evacuate the reaction chamber, opening the first gas pipeline to introduce the first gas into the reaction chamber for a preset time, closing the valve, and measuring the change in the gas pressure of the reaction chamber;

[0014] The step of introducing the second gas into the vacuum reaction chamber through the second gas pipeline and measuring the change in the gas pressure in the reaction chamber to obtain a second pressure change rate comprises: opening the valve and the vacuum pump to evacuate the reaction chamber, opening the second gas pipeline to introduce the second gas into the reaction chamber for a preset time, closing the valve, and measuring the change in the gas pressure in the reaction chamber.

[0015] In one embodiment of the present application, the preset time is 15s-30s.

[0016] In one embodiment of the present application, a pressure gauge is used to measure the first pressure change rate and the second pressure change rate, wherein:

[0017] When the pressure of the reaction chamber measured by the pressure gauge reaches the preset pressure, the first pressure change amount and the second pressure change amount of the reaction chamber within the preset time period are measured to obtain the first pressure change rate and the second pressure change rate.

[0018] In one embodiment of the present application, the preset duration is 3-10 seconds.

[0019] In one embodiment of the present application, the preset air pressure is set at 40%-60% of the maximum range of the pressure gauge.

[0020] In one embodiment of the present application, the preset threshold value ranges from 3% to 10%.

[0021] In one embodiment of the present application, at least one of the first gas and the second gas is an inert gas.

[0022] According to a second aspect of the present application, a chemical vapor deposition machine is provided, and a flow deviation test of a mass flow controller is performed by using the calibration method of a mass flow controller as described in any one of the first aspects above.

[0023] The calibration method of the mass flow controller of the present application checks the gas flow deviation based on the reference relationship coefficient and the detection relationship coefficient obtained in the gap of the process flow executed by the equipment, so that the gas flow deviation of the machine can be detected at any time, the flow control status of the mass flow controller can be fed back, the utilization efficiency of the machine can be improved, and the detection cost can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The above and other purposes, features and advantages of the present invention will become more apparent by describing the embodiments of the present invention in more detail in conjunction with the accompanying drawings. The accompanying drawings are used to provide a further understanding of the embodiments of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings, the same reference numerals generally represent the same components or steps.

[0025] Figure 1 is a schematic flow chart of a calibration method for a mass flow controller according to an embodiment of the present application;

[0026] Figure 2 is a schematic structural diagram of a chemical vapor deposition device according to an embodiment of the present application;

[0027] Figure 3 4 is a pressure-time relationship diagram according to an embodiment of the present application. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical scheme and advantages of the present invention more obvious, the exemplary embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments of the present invention, and it should be understood that the present invention is not limited to the exemplary embodiments described herein. Based on the embodiments of the present invention described in the present invention, all other embodiments obtained by those skilled in the art without creative work should fall within the protection scope of the present invention.

[0029] In view of the problem that the existing calibration method of mass flow controller requires the machine to be shut down to execute the flow detection procedure inside the machine, the detection frequency and equipment utilization efficiency are low, resulting in high detection costs, this application proposes a calibration method for a mass flow controller and a chemical vapor deposition machine, which are described in detail below.

[0030] First, refer to Figure 1 The calibration method of the mass flow controller according to the embodiment of the present application is described.

[0031] The present application provides a calibration method for a mass flow controller, wherein a plurality of mass flow controllers include a first mass flow controller and a second mass flow controller, which are respectively arranged on a first gas pipeline and a second gas pipeline connected to the same reaction chamber.

[0032] In the present application, the reaction chamber is a sealed space, and the reaction chamber has at least two gas inlets and one gas extraction port. One end of the first gas pipeline and the second gas pipeline are connected to the gas inlet, and the other end is connected to the gas supply system. The gas supply system includes components such as a gas source, a gas transmission pipeline, and a valve, and can provide different types of gases according to actual process requirements, such as SO 3 , Cl 2 , HCl, HF and other corrosive gases as well as nitrogen, hydrogen and inert gases, etc., and are not limited thereto. It is understood that the mass flow controller, the reaction chamber, and the gas pipeline can be components of semiconductor processing equipment, and the semiconductor processing equipment includes but is not limited to the above components, and the gas flow rate entering the reaction chamber can be controlled by the mass flow controller. A pressure gauge can be provided on the reaction chamber to collect the air pressure in the reaction chamber. For example, the pressure gauge can be a vacuum gauge.

[0033] It should be noted that the semiconductor processing equipment may be a chemical vapor deposition equipment (CVD), a physical vapor deposition (PVD) equipment or an etching equipment, etc., and the embodiments of the present application are not limited thereto.

[0034] This verification method can be performed in the interval between two adjacent process treatments, that is, it can be an online verification, but is not limited to this, and can also be a verification after shutdown. Figure 1 As shown, the process specifically includes the following steps S110 to S140.

[0035] In step S110, the first mass flow controller is set to a preset flow rate, a first gas is introduced into the vacuum reaction chamber through the first gas pipeline, and a pressure change in the reaction chamber is measured to obtain a first pressure change rate.

[0036] A first gas inlet valve is provided on a first gas pipeline connected to the reaction chamber. In a specific implementation, the first gas inlet valve is opened, a gas flow rate, i.e., a preset flow rate, is set in a mass flow controller, gas is introduced into the reaction chamber, and a pressure change in the reaction chamber is measured to obtain a first pressure change rate.

[0037] In step S120, the second mass flow controller is set to a preset flow rate, a second gas is introduced into the vacuum reaction chamber through the second gas pipeline, and a gas pressure change in the reaction chamber is measured to obtain a second pressure change rate.

[0038] A second gas inlet valve is provided on a second gas pipeline connected to the reaction chamber. In a specific implementation, the second gas inlet valve is opened, a gas flow rate, i.e., a preset flow rate, is set in a mass flow controller, gas is introduced into the reaction chamber, and the gas pressure change in the reaction chamber is measured to obtain a second pressure change rate.

[0039] In the present application, the first gas and the second gas are any gas supplied by the gas supply system.

[0040] It can be understood that the preset flow rates of steps S110 and S120 are the same.

[0041] Optionally, the value range of the preset flow rate is 40%-60% of the maximum range of the MFC, that is, the value range of the preset flow rate satisfies the following relationship:

[0042] 0.4Q <p<0.6Q

[0043] Where p is the preset flow rate and Q is the maximum range of the mass flow controller.

[0044] The MFC flow rate is more accurate when it is near the middle value of the range. Therefore, when the value range of the preset flow rate satisfies the above relationship, the detection accuracy of the flow deviation can be improved.

[0045] In step S130, a detection relationship coefficient is obtained based on the first pressure change rate and the second pressure change rate.

[0046] Specifically, the detection relationship coefficient can be calculated by the following formula:

[0047] F ′ =P 2 ′ / P 1 ′

[0048] Among them, F ′ is the detection relationship coefficient, P 1 ′ is the first pressure change rate, P 2 ′ is the second pressure change rate.

[0049] Since the first pressure change rate and the second pressure change rate are measured between the intervals of two adjacent process treatments, the measurement time of the two is relatively close and the measurement environment is almost the same. By obtaining the reference relationship coefficient and the detection relationship coefficient through the ratio of the two, the fluctuation of environmental factors such as the reaction chamber volume, the reaction chamber sealing degree, the membrane degassing and the gas supply system on the detection result F can be reduced. ′ The impact of accuracy.

[0050] In step S140, when the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient is greater than a preset threshold, it is determined that at least one of the first mass flow controller and the second mass flow controller has an abnormal deviation.

[0051] In the present application, the reference relationship coefficient is used to represent the pressure change relationship generated after the first gas and the second gas are respectively delivered to the vacuum reaction chamber under the control of the accurate first mass flow controller and the second mass flow controller. Usually, the accuracy of the mass flow controller decreases with the extension of the use time. Specifically, the reference relationship coefficient can be the detection relationship coefficient measured for the first mass flow controller and the second mass flow controller used for the first 1-5 times after calibration. However, it is not limited to this. In some embodiments, the reference relationship coefficient can be any value of the detection relationship coefficient of the historical detection, depending on the specific situation.

[0052] Specifically, the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient can be calculated by the following formula:

[0053] R=|1-F ′ / F|

[0054] Among them, R is the deviation rate, F ′ is the detection relationship coefficient, and F is the reference relationship coefficient.

[0055] Preferably, the preset threshold value ranges from 3% to 10%.

[0056] Setting the value range of the preset threshold to 3%-10% can effectively meet the calibration requirements of the mass flow controller and identify its abnormal state.

[0057] In the present application, when the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient is greater than a preset threshold, it indicates that at least one mass flow controller is working abnormally, so that there is a deviation between the actual gas supply volume and the gas supply control volume of the gas supply system, and the deviation of the gas pressure change rate in the reaction chamber exceeds the normal range.

[0058] When the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient is less than or equal to a preset threshold, it indicates that there is no deviation between the actual gas supply provided by the gas supply system to the reaction chamber and the gas supply control amount, or there is a deviation but the deviation is within a normal range, and the working conditions of the two mass flow controllers are normal.

[0059] The calibration method of the mass flow controller of the present application can check the gas flow deviation by using the reference relationship coefficient and the detection relationship coefficient obtained between two process flows executed by the equipment, so that the detection can be automatically performed without stopping the equipment, thereby realizing online monitoring of the gas flow deviation of the machine, and feeding back the flow control status of the mass flow controller, thereby improving the use efficiency of the machine and reducing the detection cost.

[0060] Optionally, the mass flow controller calibration method of the present application may be performed once before each process is performed in the reaction chamber.

[0061] The following combination Figure 2-Figure 3 A calibration method for a mass flow controller according to an embodiment of the present application is described below.

[0062] The calibration method of the mass flow controller of this embodiment is applied to CVD equipment. CVD can be divided into atmospheric pressure chemical vapor deposition (APCVD), sub atmospheric pressure chemical vapor deposition (SAPCVD) and low pressure chemical vapor deposition (LPCVD). The method of this embodiment can be applied to any type of CVD equipment.

[0063] See also Figure 2 , CVD equipment usually has the following main components:

[0064] Reaction chamber 10: It is the main area for chemical reaction and thin film deposition. Reaction chamber 10 is usually made of high temperature resistant materials to accommodate reaction gas and substrate material. In reaction chamber 10, by controlling parameters such as temperature, pressure and gas flow rate, the reaction gas undergoes chemical reaction on the substrate surface and deposits to form a thin film.

[0065] Gas supply system: a system for providing reaction gas or gas mixture to the reaction chamber 10. It includes components such as a gas source (not shown in the figure), a first gas pipeline 21a, a second gas pipeline 21b, a first gas inlet valve 22a, a second gas inlet valve 22b, a first mass flow controller 23a, and a second mass flow controller 23b. The design and control of the gas supply system is crucial to the control of film composition and uniformity.

[0066] Heating system (not shown): Semiconductor CVD equipment usually requires high temperature to promote reaction and film growth. The heating system uses resistance heating, induction heating or radiation heating to provide the required high temperature conditions.

[0067] Pump system 40: a system for creating and maintaining a vacuum environment in the reaction chamber 10 and controlling the gas pressure level in the reaction chamber 10. The pump system 40 controls the pressure in the reaction chamber 10 by extracting gas to ensure that the reaction gas reacts within a suitable pressure range. The pump system 40 specifically includes an isolation valve 41 and a vacuum pump 42. The reaction chamber 10 is connected to the vacuum pump 42 via the isolation valve 41. The vacuum pump 42 can evacuate the reaction chamber 10.

[0068] Control system (not shown): used to monitor and adjust temperature, pressure, gas flow and other key parameters. The control system usually includes a processing unit and automatic control software, etc., and connects and controls the gas supply system, heating system and pump system 40 to implement the process.

[0069] In this embodiment, the first gas is argon, and the second gas can be a reaction gas or a purge gas, etc. A pressure gauge 30, such as a vacuum gauge, is provided on the reaction chamber 10, which is usually used to collect the gas pressure value in the reaction chamber 10 during the process. In this embodiment, the pressure gauge 30 can be used to measure the first pressure change rate and the second pressure change rate.

[0070] The following specifically describes the method for measuring the first pressure change rate and the second pressure change rate and the method for determining the detection relationship coefficient.

[0071] It should be noted that the measurement of the first pressure change rate and the second pressure change rate can be performed during the intervals of the machine process, and can be automatically executed using the machine program, thereby ensuring seamless operation of the machine.

[0072] In this embodiment, the measurement of the first pressure change rate and the second pressure change rate includes the following steps.

[0073] Step 1: Open the isolation valve 41 and the vacuum pump 42 to evacuate the reaction chamber 10.

[0074] Step 2: Open the first air inlet valve 22a, and introduce the first gas, i.e., argon, into the reaction chamber 10 at a preset flow rate through the first gas pipeline 21a and the first mass flow controller 23a for a preset time, then close the isolation valve 41 and use the pressure gauge 30 to measure the pressure change in the reaction chamber 10.

[0075] Step 3: stop supplying argon, open the isolation valve 41 , and evacuate the reaction chamber 10 to a vacuum state through the vacuum pump 42 .

[0076] Step 4: Open the second air inlet valve 22b, introduce the second gas into the reaction chamber 10 at a preset flow rate through the second gas pipeline 21b and the second mass flow controller 23b for a preset time, close the isolation valve 41, and use the pressure gauge 30 to measure the pressure change of the reaction chamber 10. Here, the second gas is the reaction gas.

[0077] Optionally, the preset time ranges from 15s to 30s. Before closing the isolation valve 41, the gas is introduced for a preset time and then the pressure change is measured, so that the gas flow distribution in the reaction chamber 10 is stabilized before measurement, thereby improving the measurement accuracy.

[0078] See also Figure 3 , Figure 3 The horizontal axis is time, t 1 and t 2 are the two sampling moments of the first gas, p 1 、p 2 The first gas at t 1 With t 2 The pressure value at time t 3 and t 4 are the two sampling moments of the second gas, p 3 、p 4 The second gas at t 3 With t 4 The pressure value at the moment.

[0079] It should be noted that here t 1 With t 2 The difference between 3 and t 4 The differences can be equal or unequal.

[0080] Preferably, t 1 With t 2 The difference between 3 and t 4 The difference is equal, that is, the pressure changes in the same length of time are measured, which makes it easy to calculate the pressure change rate.

[0081] Preferably, the duration of measuring the pressure change is 3-10 seconds.

[0082] Measuring pressure changes within 3-10 seconds can not only obtain accurate pressure change rate, but also avoid the impact of long-term measurement on the normal operation of the machine.

[0083] Exemplarily, using the pressure gauge 30 to measure the pressure change of the reaction chamber 10 includes: when the pressure of the reaction chamber 10 reaches a preset pressure, starting to use the pressure gauge 30 to measure the first pressure change amount and the second pressure change amount of the reaction chamber 10 within the aforementioned time period to obtain the first pressure change rate and the second pressure change rate. That is, the pressure p of the reaction chamber 10 measured by the vacuum gauge is 1 、p 3 When the pressure is set to the preset value, confirm that t 1 and t 3 time; after the aforementioned time, it reaches t 2 and t 4 At this moment, the pressure p in the reaction chamber 10 is measured. 2 、p 4 .

[0084] The calculation formula of the first pressure change is as follows:

[0085] Δp 1 =p 2 -p 1

[0086] Among them, Δp 1 is the first pressure change.

[0087] The calculation formula of the second pressure change is as follows:

[0088] Δp 2 =p 4 -p 3

[0089] Among them, Δp 2 is the second pressure change.

[0090] Preferably, the preset pressure is in the range of 40%-60% of the maximum range of the pressure gauge 30. When the pressure value measured by the pressure gauge 30 is close to the maximum range value, the measurement result is more accurate and the measurement error is smaller; therefore, the preset pressure is set to be near the middle value of the pressure sensor measurement range, and the measurement time is set so that the pressure p in the reaction chamber 10 is 2 、p 4 is closer to the maximum range of the pressure gauge 30, so that the two pressure values ​​p used to determine the first pressure change and the second pressure change are 2 、p 4The measurement error is smaller, thereby improving the detection accuracy. It can be understood that the specific measurement time can be determined according to the range of the pressure gauge 30, the first mass flow controller 23a, the second mass flow controller 23b, etc., so as to obtain a more accurate measurement result.

[0091] Step 5: Determine a detection relationship coefficient based on the first pressure change amount and the second pressure change amount.

[0092] Specifically, since the two measurements are performed at the same time, the detection relationship coefficient can be obtained by the following formula:

[0093] F ′ =Δp 2 / Δp 1

[0094] Among them, F ′ is the detection relationship coefficient.

[0095] Preferably, each time the relationship coefficient is measured, the same preset time, preset flow rate, pressure gauge 30, preset pressure and measurement duration are used, including the measurement of obtaining the reference relationship coefficient, thereby improving the accuracy of identifying the offset of the first mass flow controller 23a and the second mass flow controller 23b.

[0096] This embodiment provides a method for self-checking gas flow deviation without stopping the operation of the device, periodically obtaining the detection relationship coefficient under the same conditions, and comparing it with the reference relationship coefficient to obtain the deviation ratio. This replaces the existing device that needs to stop operation before performing gas flow correction, and improves the detection rate of equipment failure.

[0097] According to an embodiment of the present application, at least one of the first gas and the second gas is an inert gas, such as helium (He), neon (Ne), argon (Ar), etc.

[0098] Since a small amount of gas may remain in the reaction chamber, introducing inert gas can avoid reaction with the residual gas, thereby reducing measurement errors and improving calibration accuracy.

[0099] The software architecture of process control of semiconductor processing equipment includes two parts: lower computer control software and upper computer control software. The lower computer control software directly faces the process equipment and interacts with the equipment directly through the industrial computer. It is responsible for controlling the process and recording the data parameters in the process. The upper computer control software interacts with the lower computer control software and controls the automatic production of the equipment by sending control instructions to the lower computer control software, as well as realizing functions such as collecting production data, alarm processing, and equipment maintenance operations, and integrates data monitoring functions.

[0100] The upper computer control software can run on an ordinary computer, and the lower computer control software can run on an industrial computer. The two are connected via Ethernet or a data cable, and communication is achieved using an Internet Communications Engine (ICE).

[0101] In this embodiment, the host computer control software can be used to control the semiconductor processing equipment to periodically obtain the detection relationship coefficient under the same conditions, and obtain the deviation rate with the reference relationship coefficient. When the deviation rate is stable for a long time and within the normal range, it means that the flow rate of the mass flow controller is accurate.

[0102] This embodiment provides a method for verifying gas flow deviation without stopping the operation of the device, thereby replacing the existing device that needs to stop operating before performing gas flow verification, thereby improving the detection efficiency and detection rate of mass flow controller failures.

[0103] The embodiment of the present application further provides a chemical vapor deposition machine, which performs flow deviation inspection of a mass flow controller by using the mass flow controller calibration method of any of the above embodiments.

[0104] Although example embodiments have been described herein with reference to the accompanying drawings, it should be understood that the above example embodiments are merely exemplary and are not intended to limit the scope of the present invention thereto. Various changes and modifications may be made therein by one of ordinary skill in the art without departing from the scope and spirit of the present invention. All such changes and modifications are intended to be included within the scope of the present invention as required by the appended claims.

[0105] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0106] In the several embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed.

[0107] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0108] Similarly, it should be understood that in order to streamline the present invention and help understand one or more of the various inventive aspects, in the description of the exemplary embodiments of the present invention, the various features of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. However, the method of the present invention should not be interpreted as reflecting the following intention: the claimed invention requires more features than the features explicitly stated in each claim. More specifically, as reflected in the corresponding claims, the inventive point is that the corresponding technical problem can be solved with less than all the features of a single disclosed embodiment. Therefore, the claims following the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present invention.

[0109] It will be understood by those skilled in the art that, except for mutually exclusive features, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this specification may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature that provides the same, equivalent or similar purpose.

[0110] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present invention and form different embodiments. For example, in the claims, any one of the claimed embodiments may be used in any combination.

[0111] The various component embodiments of the present invention may be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or a digital signal processor may be used in practice to implement some or all of the functions of some modules in the article analysis device according to an embodiment of the present invention. The present invention may also be implemented as a device program (e.g., a computer program and a computer program product) for executing part or all of the methods described herein. Such a program implementing the present invention may be stored on a computer-readable medium, or may be in the form of one or more signals. Such a signal may be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0112] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may devise alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of a plurality of such elements. The present invention may be implemented by means of hardware comprising a number of different elements and by means of a suitably programmed computer. In a unit claim enumerating a number of devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0113] The above is only a specific embodiment of the present invention or an explanation of a specific embodiment. The protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A method for calibrating a mass flow controller, characterized in that: The plurality of mass flow controllers include a first mass flow controller and a second mass flow controller, which are respectively arranged on a first gas pipeline and a second gas pipeline connected to the same reaction chamber; the verification method includes, in the interval between two adjacent process treatments: Setting the first mass flow controller to a preset flow rate, introducing a first gas into the vacuum reaction chamber through the first gas pipeline, and measuring a pressure change in the reaction chamber to obtain a first pressure change rate; Setting the second mass flow controller to a preset flow rate, introducing a second gas into the vacuum reaction chamber through the second gas pipeline, and measuring the gas pressure change in the reaction chamber to obtain a second pressure change rate; Obtaining a detection relationship coefficient based on the first pressure change rate and the second pressure change rate; When the deviation rate between the detection relationship coefficient and the pre-obtained reference relationship coefficient is greater than a preset threshold, it is determined that at least one of the first mass flow controller and the second mass flow controller has an abnormal deviation.

2. The calibration method of a mass flow controller as claimed in claim 1, characterized in that: The preset flow rate is set at 40%-60% of the maximum range of the mass flow controller.

3. The calibration method of a mass flow controller as claimed in claim 1, characterized in that: The reaction chamber is also connected to a vacuum pump via a valve, and the vacuum pump is used to evacuate the reaction chamber; The step of introducing the first gas into the vacuum reaction chamber through the first gas pipeline and measuring the change in the gas pressure of the reaction chamber to obtain the first pressure change rate comprises: opening the valve and the vacuum pump to evacuate the reaction chamber, opening the first gas pipeline to introduce the first gas into the reaction chamber for a preset time, closing the valve, and measuring the change in the gas pressure of the reaction chamber; The step of introducing the second gas into the vacuum reaction chamber through the second gas pipeline and measuring the change in the gas pressure in the reaction chamber to obtain a second pressure change rate comprises: opening the valve and the vacuum pump to evacuate the reaction chamber, opening the second gas pipeline to introduce the second gas into the reaction chamber for a preset time, closing the valve, and measuring the change in the gas pressure in the reaction chamber.

4. The calibration method of a mass flow controller as claimed in claim 3, characterized in that: The preset time is 15s-30s.

5. The calibration method of a mass flow controller according to claim 1, characterized in that: The first pressure change rate and the second pressure change rate are measured using a pressure gauge, wherein: When the pressure of the reaction chamber measured by the pressure gauge reaches the preset pressure, the first pressure change amount and the second pressure change amount of the reaction chamber within the preset time period are measured to obtain the first pressure change rate and the second pressure change rate.

6. The calibration method of a mass flow controller according to claim 5, characterized in that: The preset duration is 3-10 seconds.

7. The calibration method for a mass flow controller according to claim 5, characterized in that: The preset air pressure is set at 40%-60% of the maximum range of the pressure gauge.

8. The calibration method of a mass flow controller according to claim 1, characterized in that: The preset threshold value ranges from 3% to 10%.

9. The calibration method of a mass flow controller according to claim 1, characterized in that: At least one of the first gas and the second gas is an inert gas.

10. A chemical vapor deposition machine, characterized in that: The flow deviation inspection of the mass flow controller is carried out by the calibration method of the mass flow controller according to any one of claims 1 to 9.

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