An adaptive preheating and conveying container automatic switching control method and system

Abstract

The application discloses an automatic switching control method and system for self-adaptive preheating and conveying containers and relates to the technical field of semiconductor integrated circuit manufacturing equipment. The method comprises the following steps: when the material consumption of a main conveying container reaches a preset threshold, the temperature of the main conveying container is self-adaptively increased based on a sublimation kinetics coupling model and a saturated vapor pressure characteristic constant to compensate for the attenuation of the sublimation rate, and the preheating target temperature of a standby conveying container is reversely determined; before switching, the excess saturated vapor pressure in the standby conveying container is smoothly released through feedback and discharge control, so that the pressure of the standby conveying container is accurately and actively aligned with the pressure of the main buffer container; during the switching process, the output adjustment components of the two conveying containers are overlapped and cross-started and stopped according to opposite complementary functions, so that the total mass flow fluctuation rate of the system is kept within a preset threshold. The application effectively eliminates the switching transient pressure peak and flow depression, realizes high-quality, uninterrupted and high-precision continuous conveying of solid-state precursors, and is suitable for semiconductor ALD / CVD thin film deposition processes.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor integrated circuit manufacturing equipment technology, and specifically relates to an adaptive preheating and automatic switching control method and system for a solid precursor delivery system. Background Technology

[0002] As semiconductor integrated circuit process nodes continue to shrink, advanced logic chip manufacturing has entered the 3-nanometer and below node, dynamic random access memory (DRAM) is evolving towards the 10-nanometer level and below, and 3D NAND flash memory is developing towards 300-layer or even 400-layer stacked technology. The manufacturing of these advanced devices places extremely stringent requirements on the material purity, deposition uniformity, and step coverage of key thin films such as metal barrier layers, word lines, via plugs, and capacitor electrodes. Molybdenum (Mo), molybdenum nitride (MoN), and molybdenum oxide (MoO) are commonly used materials in this process. x Thin films such as tungsten (W), titanium nitride (TiN), and cobalt (Co) are gradually replacing traditional tungsten (W), titanium nitride (TiN), and cobalt (Co) films due to their extremely low resistivity, excellent thermal stability, and resistance to electromigration, becoming the preferred solution for advanced interconnect and electrode materials.

[0003] In the aforementioned ALD / CVD growth process for molybdenum-containing thin films, the widely used solid precursors mainly include high-purity solid molybdenum dichlorodioxide (MoO2Cl2) and molybdenum pentachloride (MoCl5), among other transition metal halides. These solid precursors typically share the following characteristics: their saturated vapor pressure varies exponentially with temperature, they have low sublimation rates, and they are highly susceptible to the residual charge (residual charge effect) within the transport container.

[0004] However, existing solid precursor delivery systems have the following significant drawbacks in practical applications: (1) Decrease in sublimation capacity due to residual material effect: As the solid precursor material in the conveying container is consumed, the accumulation morphology of the precursor changes, and the effective sublimation surface area shrinks sharply, resulting in a significant decrease in the sublimation rate and outlet vapor pressure at the same heating temperature, which cannot meet the high-frequency, constant-pressure pulse feeding requirements of the reaction chamber. In the prior art, although there are methods to improve the conveying stability by gradually increasing the temperature (such as the scheme disclosed in Chinese patent application CN121519031A), this scheme does not establish a quantitative physical coupling relationship between the amount of solid material remaining and the decrease in sublimation rate. Therefore, it is impossible to achieve accurate adaptive compensation of heating temperature based on material consumption, and it is even more impossible to provide a scientific preheating target temperature for the standby container in the scenario of switching between two conveying containers.

[0005] (2) Pressure shock during switching: When the standby transport container is directly switched into the transport system, the saturated vapor pressure accumulated inside the standby transport container during the long-term static heating process is significantly higher than the dynamic process pressure of the main buffer container of the system. A huge pressure spike will be generated at the moment of switching, which will destroy the airflow stability and cause wafer process abnormalities or even scrap. Existing technologies have disclosed precursor supply systems with buffer containers (such as Korean Patent KR102885175B1), but they only involve using buffer containers for pressure buffering and flow control, and do not involve active pressure alignment control between the standby container and the main buffer container before switching.

[0006] (3) Sudden changes in flow resistance caused by switching valve opening and closing: In traditional switching methods of closing first and then opening or opening and closing one at a time, the total flow resistance of the pipeline will increase instantaneously during the transition time of valve opening and closing, causing a sudden drop in the flow rate of carrier gas and precursor, resulting in insufficient deposition reaction and affecting the atomic-level uniformity of film composition. Although there are online switching schemes for redundant gas supply pipelines in the prior art (such as Chinese patent application CN121496368A), they are mainly aimed at the redundant switching of liquid precursor ALD valve groups and do not involve the flow resistance matching and constant flow control during the switching process of solid precursor delivery containers.

[0007] (4) Uncontrolled transmembrane pressure difference in carrier gas removal system: In scenarios where light carrier gases (such as helium) are used as transport media to assist in the transport of materials that are difficult to sublimate, small molecules in the carrier gas may affect the quality of subsequent thin film deposition. Although a carrier gas removal system with a gas separation membrane added before entering the main buffer container can remove the carrier gas, frequent switching of transport containers and system pressure fluctuations can easily lead to uncontrolled transmembrane pressure difference across the gas separation membrane, which in turn can cause reverse permeation of precursor vapor or rupture and damage to the separation membrane. Existing liquid precursor degassing schemes mainly focus on the removal of dissolved gases in liquid precursors and do not involve the dynamic safety control of the transmembrane pressure difference of the carrier gas removal membrane during solid precursor vapor transport.

[0008] Therefore, there is an urgent need for a solid precursor delivery control method and system that can achieve adaptive temperature compensation, active pressure alignment before switching, constant flow rate during switching, and dynamic safety balance of transmembrane pressure difference in the carrier gas removal system, so as to ensure the continuous and high-quality operation of semiconductor manufacturing processes. Summary of the Invention

[0009] To address the problems in related technologies, this invention proposes an adaptive preheating and automatic switching control method and system for solid precursor delivery systems, in order to overcome the aforementioned technical problems existing in the prior art.

[0010] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: An adaptive preheating and automatic switching control method for conveying containers is provided for controlling a solid precursor conveying system. The conveying system includes a first conveying container and a second conveying container connected in parallel, and a main buffer container connected to the first and second conveying containers. The control method includes the following steps: Step S1, Adaptive Sublimation Compensation and Backup Container Preheating: Obtain the remaining amount of solid precursor material in the first conveying container currently in conveying operation; when the remaining amount of material decreases to a preset switching threshold, determine the adaptive compensation operating temperature of the first conveying container based on the sublimation kinetic model of the solid precursor; and determine the preheating target temperature of the second conveying container according to the sublimation kinetic model and the correspondence between the saturated vapor pressure and temperature of the solid precursor, and perform adaptive preheating on the second conveying container; Step S2, Dynamic Pressure Active Alignment: After the second delivery container is heated to the preheating target temperature, the internal pressure of the main buffer container and the internal pressure of the second delivery container are obtained; based on the pressure deviation between the internal pressure of the main buffer container and the internal pressure of the second delivery container, pressure relief is performed on the second delivery container through feedback control to smoothly release the gas in the second delivery container that exceeds the internal pressure of the main buffer container until the difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed the preset pressure alignment threshold. Step S3, Disturbance-free overlapping switching: After completing the pressure alignment in step S2, the output adjustment component of the first conveying container is controlled to gradually close according to the decay opening curve, while the output adjustment component of the second conveying container is controlled to gradually open according to the growth opening curve, so that there is a time overlap area between the two output adjustment components during the switching process; wherein, within the time overlap area, the fluctuation rate of the total mass flow rate of the conveying system from the first conveying container and the second conveying container into the main buffer container does not exceed a preset fluctuation rate threshold.

[0011] As a preferred technical solution, in step S1, the sublimation kinetic model is used to characterize the quantitative relationship between the sublimation rate, dynamic effective sublimation surface area, and gas phase pressure in the first delivery container of the solid precursor. The dynamic effective sublimation surface area is determined by the remaining mass, solid density, and particle geometric packing shape factor of the solid precursor, and the dynamic effective sublimation surface area decreases as the solid precursor is consumed.

[0012] As a preferred technical solution, in step S1, the degree of sublimation capacity decay caused by the consumption of solid precursor is characterized by defining a sublimation capacity decay coefficient α. The sublimation capacity decay coefficient α is positively correlated with the ratio of the current remaining material amount in the first conveying container to the full load material amount. The adaptive compensation operating temperature of the first delivery container is determined by combining the characteristic constant of the saturated vapor pressure of the solid precursor, the real-time gas phase pressure inside the first delivery container, and the current sublimation capacity decay coefficient of the first delivery container.

[0013] As a preferred technical solution, in step S1, the preheating target temperature of the second conveying container is determined jointly by the saturated vapor pressure characteristic constant of the solid precursor, the real-time gas phase pressure inside the second conveying container, and the standard sublimation pressure difference driving force when the first conveying container is fully loaded.

[0014] As a preferred technical solution, in step S2, the feedback control is proportional-integral-derivative control, and the pressure relief is performed by a relief control component installed on the relief path of the second delivery container. Once the pressure difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed a preset pressure alignment threshold, and this pressure difference condition continues for more than a preset stabilization time, the pressure alignment is determined to be complete, and the venting passage is closed.

[0015] As a preferred technical solution, in step S3, the attenuation opening curve and the growth opening curve are nonlinear functions that are opposite to each other, so that the opening of the output adjustment component of the first conveying container decreases from the initial working opening to zero, while the opening of the output adjustment component of the second conveying container increases from zero to the preset design opening.

[0016] As a preferred technical solution, the nonlinear function is an exponential function, wherein the opening degree of the output adjustment component of the first conveying container decreases with time according to a negative exponential law, and the opening degree of the output adjustment component of the second conveying container increases with time according to a complementary positive exponential law.

[0017] As a preferred technical solution, when the conveying system uses carrier gas to assist in conveying solid precursor vapor, and a carrier gas removal system for removing carrier gas is provided upstream of the main buffer container, the control method further includes: Step S4, Dynamic control of transmembrane pressure difference: Obtain the inlet side pressure and back pressure side pressure of the gas separation membrane in the carrier gas removal system, and determine the real-time transmembrane pressure difference; with the preset safe transmembrane pressure difference as the control target, adjust the pumping rate of the back pressure side of the carrier gas removal system through feedback control, and maintain the transmembrane pressure difference within a range not greater than the safe transmembrane pressure difference in real time.

[0018] As a preferred technical solution, in step S4, the intake mass flow rate of the carrier gas system is simultaneously subjected to linked feedforward control, and the intake mass flow rate of the carrier gas system is adjusted by feedforward compensation according to the rate of change of the intake side pressure.

[0019] The present invention also provides a solid precursor delivery system for performing the control method described above, comprising: The first and second conveying containers, arranged in parallel, are used to contain solid precursors, respectively. A material quantity detection unit is used to obtain the remaining material quantity of the solid precursor in the first conveying container and / or the second conveying container; A temperature control unit, thermally coupled to the first and second conveying containers, is used to control the heating temperature of each conveying container respectively. The main buffer container is connected to the first and second conveying containers respectively via conveying pipelines; The pressure detection unit is used to acquire the internal pressure of the main buffer container and the internal pressure of the second delivery container; A venting control component, connected to the gas phase space of the second delivery container, is used to controllably release the gas in the second delivery container to the venting line; A first output adjustment component is disposed on the conveying pipeline between the first conveying container and the main buffer container; The second output adjustment component is disposed on the conveying pipeline between the second conveying container and the main buffer container; The controller is communicatively connected to the material quantity detection unit, the temperature control unit, the pressure detection unit, the venting control component, the first output adjustment component, and the second output adjustment component, and the controller is configured to execute the control method as described above.

[0020] As a preferred technical solution, a carrier gas removal subsystem is also included, the carrier gas removal subsystem comprising: A gas separation membrane is disposed upstream of the main buffer container. The gas separation membrane has an inlet side and a back pressure side and is used to remove the carrier gas before the mixed gas enters the main buffer container. The pressure detection unit is also used to acquire the inlet side pressure and back pressure side pressure of the gas separation membrane; A back-pressure side air extraction regulating component is installed on the back-pressure side pipeline of the gas separation membrane and is used to regulate the back-pressure side air extraction rate. The controller is also communicatively connected to the back pressure side air extraction regulating component and configured to perform the transmembrane pressure difference dynamic control steps as described above.

[0021] Compared with the prior art, the present invention has the following beneficial effects: (1) Precise adaptive compensation for residual material effect: By establishing a dynamic physical coupling model between sublimation rate and residual material amount, and combining the characteristic constant of saturated vapor pressure of solid precursor for nonlinear calculation, this method can accurately and smoothly increase the adaptive heating temperature of working conveying container as material is consumed, and scientifically predict the optimal preheating temperature of standby conveying container in reverse, fundamentally solving the problem of the drop in conveying steam amount caused by the reduction of residual amount of solid material.

[0022] (2) Completely eliminate transient pressure shock during switching: Before the online switching of the two delivery containers, the dynamic pressure active alignment control program is used to smoothly discharge the excessively high saturated vapor pressure accumulated in the standby delivery container to the extraction pipeline through a high-precision feedback venting algorithm, ensuring that the pressure of the standby delivery container is precisely aligned with the pressure of the main buffer container of the system, effectively eliminating the pressure spike impact on the main system and wafer process caused by the traditional hard switching instant.

[0023] (3) Maintain constant flow rate during switching: During the switching process, a non-disturbance overlapping switching control based on opposite nonlinear functions is adopted. During the switching transition period, the opening degree of the output adjustment components of the two delivery containers changes complementaryly. Through flow resistance linearization correction, the fluctuation rate of the total mass flow rate of the system is controlled within the preset threshold, effectively avoiding flow dip and ensuring film thickness and deposition uniformity.

[0024] (4) Effectively protect the gas separation membrane and ensure the removal efficiency of the carrier gas: By introducing dynamic tracking control of the transmembrane pressure difference, the pressure difference on both sides of the gas separation membrane is maintained in real time within the range of no more than the safety setting value, which not only ensures the efficient removal of the carrier gas and prevents the contamination of the deposition chamber by light small molecules, but also eliminates the risk of destructive rupture of the gas separation membrane caused by the transient large pressure difference during switching or pressurization.

[0025] (5) Significantly improve the continuous operation capability of semiconductor manufacturing: The four-stage collaborative control of the present invention—adaptive preheating, dynamic pressure active alignment, disturbance-free overlapping switching, and transmembrane pressure difference dynamic control—forms a complete closed-loop control chain, enabling the solid precursor delivery system to achieve "zero disturbance" during the switching process of dual delivery containers, ensuring uninterrupted high-quality operation of the semiconductor production line. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a flowchart illustrating an adaptive preheating and automatic switching control method for conveying containers according to the present invention. Figure 2 This is a schematic diagram of the structure of a solid precursor delivery system according to the present invention; Figure 3 This is a time-varying characteristic diagram of an adaptive preheating and automatic switching control method for conveying containers according to the present invention.

[0028] Wherein: 10-first conveying container, 20-second conveying container, 30-material quantity detection unit, 40-temperature control unit, 50-main buffer container, 60-pressure detection unit, 70-first output adjustment component, 80-second output adjustment component, 90-release control component, 100-controller, 110-gas separation membrane. Detailed Implementation

[0029] The technical solutions of the embodiments of the invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the invention, and not all embodiments. Based on the embodiments of the invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the invention.

[0030] In the description of this invention, it should be understood that the terms "opening", "upper", "lower", "top", "middle", "inner", etc., which indicate orientation or positional relationship, are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the invention.

[0031] refer to Figure 1 As shown, an adaptive preheating and automatic switching control method for conveying containers is disclosed. The conveying system includes a first conveying container and a second conveying container arranged in parallel, and a main buffer container connected to the first conveying container and the second conveying container. The control method includes the following steps: Step S1, Adaptive Sublimation Compensation and Backup Container Preheating: Obtain the remaining amount of solid precursor material in the first conveying container currently in conveying operation; when the remaining amount of material decreases to a preset switching threshold, determine the adaptive compensation operating temperature of the first conveying container based on the sublimation kinetic model of the solid precursor; and determine the preheating target temperature of the second conveying container according to the sublimation kinetic model and the correspondence between the saturated vapor pressure and temperature of the solid precursor, and perform adaptive preheating on the second conveying container; Step S2, Dynamic Pressure Active Alignment: After the second delivery container is heated to the preheating target temperature, the internal pressure of the main buffer container and the internal pressure of the second delivery container are obtained; based on the pressure deviation between the internal pressure of the main buffer container and the internal pressure of the second delivery container, pressure relief is performed on the second delivery container through feedback control to smoothly release the gas in the second delivery container that exceeds the internal pressure of the main buffer container until the difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed the preset pressure alignment threshold. Step S3, Disturbance-free overlapping switching: After completing the pressure alignment in step S2, the output adjustment component of the first conveying container is controlled to gradually close according to the decay opening curve, while the output adjustment component of the second conveying container is controlled to gradually open according to the growth opening curve, so that there is a time overlap area between the two output adjustment components during the switching process; wherein, within the time overlap area, the fluctuation rate of the total mass flow rate of the conveying system from the first conveying container and the second conveying container into the main buffer container does not exceed a preset fluctuation rate threshold.

[0032] As a preferred technical solution, in step S1, the sublimation kinetic model is used to characterize the quantitative relationship between the sublimation rate, dynamic effective sublimation surface area, and gas phase pressure in the first delivery container of the solid precursor. The dynamic effective sublimation surface area is determined by the remaining mass, solid density, and particle geometric packing shape factor of the solid precursor, and the dynamic effective sublimation surface area decreases as the solid precursor is consumed.

[0033] As a preferred technical solution, in step S1, the degree of sublimation capacity decay caused by the consumption of solid precursor is characterized by defining a sublimation capacity decay coefficient α. The sublimation capacity decay coefficient α is positively correlated with the ratio of the current remaining material amount in the first conveying container to the full load material amount. The adaptive compensation operating temperature of the first delivery container is determined by combining the characteristic constant of the saturated vapor pressure of the solid precursor, the real-time gas phase pressure inside the first delivery container, and the current sublimation capacity decay coefficient of the first delivery container.

[0034] As a preferred technical solution, in step S1, the preheating target temperature of the second conveying container is determined jointly by the saturated vapor pressure characteristic constant of the solid precursor, the real-time gas phase pressure inside the second conveying container, and the standard sublimation pressure difference driving force when the first conveying container is fully loaded.

[0035] As a preferred technical solution, in step S2, the feedback control is proportional-integral-derivative control, and the pressure relief is performed by a relief control component installed on the relief path of the second delivery container. Once the pressure difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed a preset pressure alignment threshold, and this pressure difference condition continues for more than a preset stabilization time, the pressure alignment is determined to be complete, and the venting passage is closed.

[0036] As a preferred technical solution, in step S3, the attenuation opening curve and the growth opening curve are nonlinear functions that are opposite to each other, so that the opening of the output adjustment component of the first conveying container decreases from the initial working opening to zero, while the opening of the output adjustment component of the second conveying container increases from zero to the preset design opening.

[0037] As a preferred technical solution, the nonlinear function is an exponential function, wherein the opening degree of the output adjustment component of the first conveying container decreases with time according to a negative exponential law, and the opening degree of the output adjustment component of the second conveying container increases with time according to a complementary positive exponential law.

[0038] As a preferred technical solution, when the conveying system uses carrier gas to assist in conveying solid precursor vapor, and a carrier gas removal system for removing carrier gas is provided upstream of the main buffer container, the control method further includes: Step S4, Dynamic control of transmembrane pressure difference: Obtain the inlet side pressure and back pressure side pressure of the gas separation membrane in the carrier gas removal system, and determine the real-time transmembrane pressure difference; with the preset safe transmembrane pressure difference as the control target, adjust the pumping rate of the back pressure side of the carrier gas removal system through feedback control, and maintain the transmembrane pressure difference within a range not greater than the safe transmembrane pressure difference in real time.

[0039] As a preferred technical solution, in step S4, the intake mass flow rate of the carrier gas system is simultaneously subjected to linked feedforward control, and the intake mass flow rate of the carrier gas system is adjusted by feedforward compensation according to the rate of change of the intake side pressure.

[0040] refer to Figure 2 As shown, the present invention also provides a solid precursor delivery system for executing the control method described above, comprising: The first conveying container 10 and the second conveying container 20, which are arranged in parallel, are respectively used to contain solid precursors; Material quantity detection unit 30 is used to obtain the remaining material quantity of solid precursor in the first conveying container 10 and / or the second conveying container 20; Temperature control unit 40 is thermally coupled to the first conveying container 10 and the second conveying container 20, and is used to control the heating temperature of each conveying container respectively; The main buffer container 50 is connected to the first conveying container 10 and the second conveying container 20 respectively through conveying pipelines; Pressure detection unit 60 is used to acquire the internal pressure of the main buffer container 50 and the internal pressure of the second delivery container 20; The venting control component 90 is connected to the gas phase space of the second delivery container 20 and is used to controllably release the gas in the second delivery container 20 to the venting pipeline. The first output adjustment component 70 is disposed on the conveying pipeline between the first conveying container 10 and the main buffer container 50; The second output adjustment component 80 is disposed on the conveying pipeline between the second conveying container 20 and the main buffer container 50; The controller 100 is communicatively connected to the material quantity detection unit 30, the temperature control unit 40, the pressure detection unit 60, the venting control component 90, the first output adjustment component 70, and the second output adjustment component 80. The controller 100 is configured to execute the control method described above.

[0041] The present invention also includes a carrier gas removal subsystem, the carrier gas removal subsystem comprising: A gas separation membrane 110 is disposed upstream of the main buffer container 50. The gas separation membrane 110 has an inlet side and a back pressure side and is used to remove the carrier gas before the mixed gas enters the main buffer container 50. The pressure detection unit 60 is also used to acquire the inlet side pressure and back pressure side pressure of the gas separation membrane 110; A back-pressure side air extraction regulating component is installed on the back-pressure side pipeline of the gas separation membrane 110 and is used to regulate the back-pressure side air extraction rate. The controller 100 is also communicatively connected to the back pressure side air extraction regulating component and configured to perform the transmembrane pressure difference dynamic control steps as described above.

[0042] refer to Figure 1-3 As shown, the method steps, formula applications, and key parameter values ​​of the present invention will be described in detail below with reference to specific embodiments.

[0043] Example 1: Solid precursor delivery switching without carrier gas assistance (taking molybdenum dioxide (MoO2Cl2) as an example) In this embodiment, molybdenum dioxide (MoO2Cl2) is used as a solid precursor, which has a high saturated vapor pressure and can be directly sublimated and transported without the assistance of a carrier gas. The carrier gas removal system in the system is in bypass mode and does not participate in the operation of this embodiment.

[0044] 1. Calibration of physical parameters and Antoine characteristic constants The basic physical parameters of the solid precursor MoO2Cl2 are as follows: ; The Antoine characteristic constants (pressure unit Pa, temperature unit K) were obtained by fitting the saturated vapor pressure experimental data of MoO2Cl2 using the nonlinear least squares method. A=11.235; B=3014.2K; C=-15.15K.

[0045] 2. Adaptive preheating calculation and execution process The material quantity detection unit (a high-precision electronic scale in this embodiment) of the first conveying container (hereinafter referred to as "main container A") transmits the current remaining precursor mass in real time. When the material is consumed down to the remaining mass m rem When (t) = 6000.0g (i.e., the remaining percentage is 15%), the switching procedure is triggered.

[0046] (a) Calculate the sublimation capacity decay coefficient of the main container A: ; The physical meaning of this decay coefficient is: when 15% of the material remains, the effective sublimation surface area has shrunk to about 28.2% of that at full load, meaning that the sublimation capacity has decreased to less than one-third.

[0047] (b) Calculate the real-time compensation pressure difference required by the main container A to maintain the design flow rate: ; (c) Calculate the required compensated saturated vapor pressure for main vessel A: ; (d) Substitute into the Antoine equation to calculate the adaptive operating temperature of the main container A: ; Converted to Celsius: 377.74 - 273.15 ≈ 104.6℃. (Note: The initial full-load operating temperature was designed to be 337.85K, or 64.7℃. Since only 15% of the material remained, the temperature automatically compensated and increased by approximately 39.9℃, successfully maintaining the sublimation pressure and mass flow rate without decrease.)

[0048] (e) Simultaneously calculate the preheating target temperature of standby container B: standby container B is in a fully loaded state (α) decay,B =1.0), and its opening instant must perfectly match the current dynamic sublimation rate of the main container A. The fully loaded container only needs to generate the designed standard sublimation pressure differential driving force ΔP upon initial opening. design =200.0Pa: ; ; Converted to Celsius: 361.02 - 273.15 ≈ 87.9℃. Based on this, the system controls the temperature control unit of container B, smoothly preheating and stabilizing it at 87.9℃. This temperature is far lower than the current 104.6℃ of the main container A, but sufficient to allow the fully loaded container B to achieve the same actual sublimation rate as the residual container A, avoiding the risk of internal pressure overshoot caused by directly heating container B to the current temperature of the main container A.

[0049] 3. Dynamic pressure active alignment process After container B is preheated to a stable temperature of 87.9°C, its internal static saturation pressure is approximately 333.3 Pa (corresponding to the calculated value of the Antoine equation at 87.9°C), while the real-time dynamic operating pressure of the main buffer container M is 133.3 Pa. There is a pressure difference of approximately 200.0 Pa between the two containers. If the output regulation component of container B is directly connected to the system, a severe pressure shock will occur.

[0050] The feedback discharge control program is activated, and the discharge control component (in this embodiment, the discharge control proportional valve V) on the discharge path of container B is activated. B,vent Start. The PID control coefficients, calibrated using a loop-through step response experiment, are as follows: proportionality coefficient K p,p =0.05% / Pa Integral coefficient K i,p =0.008% / (Pa·s) Differential coefficient K d,p =0.001%·s / Pa The PID controller adjusts the opening of the venting control component in real time, smoothly discharging the excess vapor pressure of approximately 200.0 Pa in container B to the extraction pipeline, gradually reducing the pressure inside container B to approach the pressure of the main buffer container. When it detects: ; Furthermore, if the duration of this state is t≥5s, the discharge control component V should be immediately shut down. B,vent At this point, the actual pressure inside container B has been precisely controlled at approximately 138 Pa, which is highly aligned with the pressure of the main buffer container (133.3 Pa), thus completing the dynamic pressure active alignment.

[0051] 4. Disturbance-free overlapping handover process The total switching time is set to 20 seconds, and the switching time constant is τ. switch =4.0s.

[0052] Switching at start (t=0): Container A's output regulation component V AInitial opening: V A,0 =65% Container B's output regulation component V B Preset design opening: V B,max =55% (Calculated based on the full-load flow resistance characteristics of container B) Container A's output regulation component V A Gradually close according to the nonlinear decay exponential curve: ; Container B's output regulation component V B Gradually opening according to the nonlinear growth exponential curve (with V) A (Synchronous startup) ; The two curves mentioned above are exponential functions that are opposite to each other, forming a complementary and intersecting relationship.

[0053] The flow resistance linearization correction factor was calibrated to γ flow =1.15, this factor was obtained by fitting the flow resistance characteristics of each component under different component opening degrees through experiments. The overlapping opening time of the two components is: ; During this overlap, both components jointly feed material into the main buffer container M. Through flow resistance linearization correction, the total flow resistance R of the conveying system is reduced. total (t) satisfies: ; The volatility of total flow resistance is controlled within ±0.2%.

[0054] At t=20s: V A (20) = 65%·e^(-5) ≈ 0.44% (close to complete shutdown) V B (20)≈54.63% (reaching the design working level) Container A has completely ceased operation, and Container B has officially begun working as the main delivery container.

[0055] Figure 3 As shown in the figure, during the entire switching phase, the pressure P of the main buffer container... M The fluctuation is only ±0.4Pa (equivalent to ±0.3%), meaning that the Q total mass flow rate fluctuation from the two delivery containers into the main buffer container is far below the preset fluctuation rate threshold of ±0.5%, and does not cause any process disturbance to the downstream reaction chamber, achieving a truly disturbance-free switching.

[0056] Example 2: Solid precursor delivery switching using a carrier gas and membrane degassing system (taking molybdenum pentachloride MoCl5 as an example) In this embodiment, molybdenum pentachloride (MoCl5) is used as a solid precursor. Since the saturated vapor pressure of MoCl5 is much lower than that of MoO2Cl2, it is extremely difficult to achieve effective pure sublimation transport. Therefore, high-purity helium (He) must be used as a carrier gas to assist in bubbling transport. A gas separation membrane carrier gas removal subsystem based on a porous inorganic polymer hollow fiber membrane is connected upstream of the main buffer container M, and the degassing subsystem is in operation.

[0057] 1. Calibration of physical parameters and Antoine characteristic constants The basic physical parameters of the solid precursor MoCl5 are as follows: ; The Antoine characteristic constants (pressure unit Pa, temperature unit K) of MoCl5 were obtained by fitting gas-solid equilibrium experimental data: A=12.842; B=3980.5K; C=-22.30K.

[0058] 2. Adaptive preheating calculation and execution process When the material quantity detection unit of main container A detects the remaining mass m of the precursor rem When (t) = 225.0g (i.e., the remaining proportion is 15%), the switching procedure is started.

[0059] (a) Calculate the sublimation capacity decay coefficient of the main container A: ; (b) Calculate the real-time compensation pressure difference and compensation saturated vapor pressure: ; ; (c) Calculate the adaptive operating temperature of the main container A: ; Converted to Celsius: approximately 155.05℃. (Note: The initial design full-load operating temperature was 389.15K, or 116.0℃, which was increased by approximately 39.05℃ due to automatic temperature compensation.) (d) Calculate the preheating target temperature of the standby container B: ; ; Converted to degrees Celsius: approximately 139.76℃. The temperature control unit controls container B to preheat smoothly and stabilize at this temperature.

[0060] 3. Dynamic pressure active alignment and carrier gas balancing process While container B is steadily preheated to 139.76°C, adaptive adjustment of the bubbling carrier gas flow rate is initiated. During the closed-loop preheating period, standby container B accumulates approximately 450 Pa of static pressure. The pressure inside container B is reduced to the same level as the main buffer container pressure P through PID control in the venting loop. M =200.0Pa alignment. When |P B -P M If the pressure is 6Pa≤10Pa and the duration reaches 5s, the active pressure alignment is considered complete.

[0061] 4. Dynamic control process of transmembrane pressure difference in carrier gas removal subsystem Because high-purity helium gas with a flow rate of 100 sccm is introduced as a carrier gas to assist in the transport of precursor vapor, the helium must be removed by the carrier gas removal subsystem before the mixed gas enters the main buffer container M. Throughout the automatic switching and material transport process, the transmembrane pressure differential dynamic tracking control module operates in real time.

[0062] (a) Pressure differential maintenance under normal operating conditions: The real-time pressure P is measured by the absolute pressure sensor on the inlet side of the gas separation membrane in the carrier gas removal subsystem. gas (t) = 240.0 Pa. The set safe transmembrane pressure difference ΔP set =1200.0 Pa. The controller calculates the target absolute pressure that needs to be maintained on the back pressure side in real time.

[0063] Because of P gas (t)-ΔP set =240.0-1200.0<0 indicates that the back pressure side must be in a high vacuum state—that is, the back pressure side must be evacuated to the maximum extent by a vacuum pump so that the absolute pressure on the back pressure side approaches zero. The actual transmembrane pressure difference is locked at about 240.0 Pa, which is far below the maximum pressure resistance limit of the gas separation membrane of 1200.0 Pa, ensuring safe operation.

[0064] (b) Differential pressure protection under transient high-flow-rate scouring conditions: During the high-flow-rate flushing phase of the system, the intake-side pressure P gas When the pressure (t) suddenly increases to 1500.0 Pa, if the back pressure side still maintains the original ultimate high vacuum state, the actual transmembrane pressure difference will instantly reach about 1500.0 Pa, exceeding the mechanical bearing limit (1200.0 Pa) of the gas separation membrane, and facing the risk of rupture.

[0065] At this moment, the transmembrane pressure differential dynamic control module responds quickly. The back pressure side suction regulating component (in this embodiment, a high-frequency proportional regulating valve) operates according to the calibrated PI parameters (proportional constant K). p,v =0.08% / Pa, integration constant K i,v=0.012% / (Pa·s)) Rapidly reduce the opening of the pumping unit and actively backfill a small amount of inert gas into the back pressure side to reduce the back pressure side pressure P vac (t) Rapidly rises and locks in: ; At this point, the transmembrane pressure difference is precisely controlled at a safe setpoint of 1200.0 Pa, which not only achieves high-efficiency helium removal (≥99.8%), but also completely eliminates the risk of transient pressure difference damage to the gas separation membrane caused by pressure fluctuations.

[0066] (c) Feedforward control of carrier gas flow: While controlling the transmembrane pressure difference, the inlet mass flow rate of the carrier gas system is simultaneously controlled via feedforward. The carrier gas flow rate Q is determined based on the membrane removal impedance matching coefficient β (calculated from the helium permeability and removal rate in the membrane material at the current temperature) and the transient pressure change feedforward coefficient η (η = 0.005 s / Pa in this embodiment). carrier (t) Based on the rate of change of intake side pressure dP gas (t) / dt is adjusted using feedforward compensation: ; After the dual delivery container switch is completed, the carrier gas flow rate gradually and smoothly recovers to the nominal target value of 100 sccm.

[0067] The scope of application of the control method described in this invention is not limited to molybdenum dioxide (MoO2Cl2) and molybdenum pentachloride (MoCl5) in the above embodiments. Those skilled in the art will understand that for other solid precursor materials—including but not limited to halides of transition metals and main group elements such as aluminum trichloride (AlCl3), hafnium tetrachloride (HfCl4), zirconium tetrachloride (ZrCl4), tantalum pentachloride (TaCl5), and tungsten hexachloride (WCl6)—as long as their corresponding Antoine characteristic constants (A, B, C) and solid density (ρ) are obtained… solid Basic physical properties such as ) and calibrated the standard sublimation pressure differential driving force (ΔP) for system design. design This information can be substituted into the computational framework and control logic described in this invention to achieve the same adaptive preheating and automatic switching control effects.

[0068] Similarly, the carrier gas is not limited to helium (He), but can also be argon (Ar), nitrogen (N2), or other inert gases that do not chemically react with the solid precursor. The material of the gas separation membrane can be selected based on the specific carrier gas type and process temperature, including but not limited to porous inorganic ceramic membranes, fluoropolymer hollow fiber membranes, or metal-organic framework membranes. The material quantity detection unit is not limited to electronic scales, but can also be other sensors or devices capable of obtaining the remaining material in the conveying container, such as ultrasonic level gauges or capacitive level sensors. The output adjustment component is not limited to a specific type of valve, but can also be a mass flow controller (MFC) or other flow regulation device. The discharge control component is not limited to proportional control valves, but can also be other types of controllable discharge devices.

[0069] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0070] The preferred embodiments of the invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An adaptive preheating and automatic switching control method for conveying containers, characterized in that, Includes the following steps: Step S1, Adaptive Sublimation Compensation and Backup Container Preheating: Obtain the remaining amount of solid precursor material in the first conveying container currently in conveying operation; when the remaining amount of material decreases to a preset switching threshold, determine the adaptive compensation operating temperature of the first conveying container based on the sublimation kinetic model of the solid precursor; and determine the preheating target temperature of the second conveying container according to the sublimation kinetic model and the correspondence between the saturated vapor pressure and temperature of the solid precursor, and perform adaptive preheating on the second conveying container; Step S2, Dynamic Pressure Active Alignment: After the second delivery container is heated to the preheating target temperature, the internal pressure of the main buffer container and the internal pressure of the second delivery container are obtained; based on the pressure deviation between the internal pressure of the main buffer container and the internal pressure of the second delivery container, pressure relief is performed on the second delivery container through feedback control to smoothly release the gas in the second delivery container that exceeds the internal pressure of the main buffer container until the difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed the preset pressure alignment threshold. Step S3, Disturbance-free overlapping switching: After completing the pressure alignment in step S2, the output adjustment component of the first delivery container is controlled to gradually close according to the decay opening curve, while the output adjustment component of the second delivery container is controlled to gradually open according to the growth opening curve, so that there is a time overlap area between the two output adjustment components during the switching process; wherein, within the time overlap area, the fluctuation rate of the total mass flow rate from the first delivery container and the second delivery container into the main buffer container does not exceed a preset fluctuation rate threshold. In step S1, the sublimation kinetic model is used to characterize the quantitative relationship between the sublimation rate, dynamic effective sublimation surface area, and gas phase pressure in the first delivery container of the solid precursor. The dynamic effective sublimation surface area is determined by the remaining mass, solid density and particle geometric packing shape factor of the solid precursor, and the dynamic effective sublimation surface area decreases as the solid precursor is consumed; In step S1, the degree of sublimation capacity decay caused by the consumption of solid precursor is characterized by the sublimation capacity decay coefficient α. The sublimation capacity decay coefficient α is positively correlated with the ratio of the current remaining material in the first conveying container to the full load material. The adaptive compensation operating temperature of the first delivery container is determined by combining the characteristic constant of the saturated vapor pressure of the solid precursor, the real-time gas phase pressure inside the first delivery container, and the current sublimation capacity decay coefficient of the first delivery container. In step S1, the preheating target temperature of the second delivery container is determined by combining the characteristic constant of the saturated vapor pressure of the solid precursor, the real-time gas phase pressure inside the second delivery container, and the standard sublimation pressure difference driving force when the first delivery container is fully loaded.

2. The control method according to claim 1, characterized in that, In step S2, the feedback control is a proportional-integral-derivative control, and the pressure relief is performed by a relief control component installed on the relief path of the second delivery container. Once the pressure difference between the internal pressure of the second delivery container and the internal pressure of the main buffer container does not exceed a preset pressure alignment threshold, and this pressure difference condition continues for more than a preset stabilization time, the pressure alignment is determined to be complete, and the venting passage is closed.

3. The control method according to claim 1, characterized in that, In step S3, the attenuation opening curve and the growth opening curve are nonlinear functions that are opposite to each other, so that the opening of the output adjustment component of the first conveying container decreases from the initial working opening to zero, while the opening of the output adjustment component of the second conveying container increases from zero to the preset design opening.

4. The control method according to claim 3, characterized in that, The nonlinear function is an exponential function. The opening degree of the output adjustment component of the first conveying container decreases with time according to a negative exponential law, while the opening degree of the output adjustment component of the second conveying container increases with time according to a complementary positive exponential law.

5. The control method according to claim 1, characterized in that, When a carrier gas is used to assist in the transport of solid precursor vapor, and a carrier gas removal system for removing the carrier gas is provided upstream of the main buffer container, the control method further includes: Step S4, Dynamic control of transmembrane pressure difference: Obtain the inlet side pressure and back pressure side pressure of the gas separation membrane in the carrier gas removal system, and determine the real-time transmembrane pressure difference; with the preset safe transmembrane pressure difference as the control target, adjust the pumping rate of the back pressure side of the carrier gas removal system through feedback control, and maintain the transmembrane pressure difference within a range not greater than the safe transmembrane pressure difference in real time.

6. A solid precursor delivery system for executing the control method according to any one of claims 1 to 4, characterized in that, include: The first and second conveying containers, arranged in parallel, are used to contain solid precursors, respectively. A material quantity detection unit is used to obtain the remaining material quantity of the solid precursor in the first conveying container and / or the second conveying container; A temperature control unit, thermally coupled to the first and second conveying containers, is used to control the heating temperature of each conveying container respectively. The main buffer container is connected to the first and second conveying containers respectively via conveying pipelines; The pressure detection unit is used to acquire the internal pressure of the main buffer container and the internal pressure of the second delivery container; A venting control component, connected to the gas phase space of the second delivery container, is used to controllably release the gas in the second delivery container to the venting line; A first output adjustment component is disposed on the conveying pipeline between the first conveying container and the main buffer container; The second output adjustment component is disposed on the conveying pipeline between the second conveying container and the main buffer container; The controller is communicatively connected to the material quantity detection unit, the temperature control unit, the pressure detection unit, the venting control component, the first output adjustment component, and the second output adjustment component.

7. The solid precursor delivery system according to claim 6, characterized in that, It also includes a carrier gas removal subsystem, which comprises: A gas separation membrane is disposed upstream of the main buffer container. The gas separation membrane has an inlet side and a back pressure side and is used to remove the carrier gas before the mixed gas enters the main buffer container. The pressure detection unit is also used to acquire the inlet side pressure and back pressure side pressure of the gas separation membrane; A back-pressure side air extraction regulating component is installed on the back-pressure side pipeline of the gas separation membrane and is used to regulate the back-pressure side air extraction rate. The controller is also communicatively connected to the back pressure side air extraction regulating component and configured to perform the transmembrane pressure difference dynamic control step of the control method as described in claim 5.

Images