Corrosion-resistant coating deposition method, precursor delivery piping system, atomic layer deposition machine

Abstract

The method for depositing corrosion-resistant coating, precursor delivery pipeline system and atomic layer deposition machine include: heating the pipeline to a deposition temperature by using a heating component arranged outside the pipeline; repeatedly performing multiple film layer deposition treatments on the inner wall surface of the internal flow channel to form a corrosion-resistant coating; the film layer deposition treatment step includes: introducing a first precursor into the heated delivery pipeline system; introducing a first inert gas into the delivery pipeline system to perform a first purging treatment; introducing a second precursor into the delivery pipeline system to form a corrosion-resistant sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber; introducing a second inert gas into the delivery pipeline system to perform a second purging treatment; performing a third purging treatment on the delivery pipeline system; adjusting the temperature of the delivery pipeline system from the deposition temperature to a temperature for delivering a process corrosive precursor. The reliability of the precursor delivery pipeline system and the performance of the atomic layer deposition equipment are improved.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of semiconductor manufacturing, and in particular to a method for depositing an anti-corrosion coating, a precursor delivery pipeline system, and an atomic layer deposition machine. Background Technology

[0002] With the advent of the nanoscale era in integrated circuit manufacturing, atomic layer deposition (ALD) technology has become a key process for semiconductor thin film preparation due to its precise thickness control and excellent step coverage capabilities. In the ALD process, precursors for thin film deposition are transported from multiple precursor sources to the reaction chamber via a precursor transport pipeline system. The precursors then undergo an atomic layer deposition reaction on the surface of the substrate placed within the reaction chamber to form the desired thin film. As the transport channel for the precursors, the inner wall of the precursor transport pipeline system is in direct contact with the precursors during transport. Therefore, the inner wall of the precursor transport pipeline system must be resistant to precursor corrosion to ensure process reliability and equipment lifespan.

[0003] Precursor transport piping systems typically consist of interconnected pipes and reaction chambers, the inner surfaces of which together define the internal flow channels for the precursor. When the transported process precursor is corrosive, the inner surfaces of these flow channels are continuously exposed to the corrosive medium.

[0004] Currently, the reliability of the precursor transport pipeline system for atomic layer deposition (ALD) equipment and the performance of ALD equipment still need to be improved. Summary of the Invention

[0005] The problem solved by the embodiments of the present invention is to provide an anti-corrosion coating deposition method, a precursor delivery pipeline system, and an atomic layer deposition (ALD) machine, thereby improving the reliability of the precursor delivery pipeline system of the ALD machine and the performance of the ALD equipment.

[0006] To address the aforementioned problems, this invention provides a method for depositing an anti-corrosion coating on the inner wall of a precursor transport pipeline system for an atomic layer deposition (ALD) machine. The transport pipeline system includes interconnected pipes and a reaction chamber. The inner wall surfaces of the pipes and the reaction chamber define internal flow channels, and the reaction chamber has a temperature control unit. The method includes: with the transport pipeline system already installed and before the initial introduction of a corrosive precursor for the process, heating the pipes to a deposition temperature using a heating element located outside the pipes; repeatedly performing film deposition treatments on the inner wall surface of the internal flow channels to form an anti-corrosion coating until the thickness of the anti-corrosion coating reaches a preset thickness. The anti-corrosion coating is composed of anti-corrosion sub-coatings formed in each film deposition treatment. During the film deposition process, the temperature of the reaction chamber is set independently of the pipe temperature by the temperature control unit. The film deposition step includes: introducing a first precursor into the heated transport pipeline system, causing the first precursor to chemically... The precursor is adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. A first inert gas is introduced into the transport pipeline system for a first purging treatment to remove unadsorbed first precursor and byproducts generated by chemisorption. After the first purging treatment, a second precursor is introduced into the transport pipeline system to allow the second precursor to undergo a self-limiting chemical reaction with the first precursor chemisorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming the anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. After the anti-corrosion sub-coating is formed, a second inert gas is introduced into the transport pipeline system for a second purging treatment to remove unreacted second precursor and byproducts generated by the self-limiting chemical reaction. After the anti-corrosion coating reaches a preset thickness, the transport pipeline system undergoes a third purging treatment. After the third purging treatment, the temperature of the transport pipeline system is adjusted from the deposition temperature to the temperature used for transporting the process corrosive precursor.

[0007] Optionally, the pipeline has a valve mounting position; before heating the transport pipeline system to the deposition temperature, the deposition method further includes: sealing the valve mounting position with a blind flange; after the anti-corrosion coating reaches the preset thickness, before adjusting the temperature of the transport pipeline system from the deposition temperature to a temperature for transporting the process corrosive precursor, the deposition method further includes: removing the blind flange; installing a valve at the valve mounting position; and performing the film deposition treatment step again on the transport pipeline system after the valve is installed to form the anti-corrosion coating on the inner wall surface of the valve.

[0008] Optionally, the pipeline has a valve mounting position, and the transport pipeline system further includes a valve installed at the valve mounting position, the internal flow channel being defined by the inner wall surface of the valve; in the step of introducing a first precursor into the heated transport pipeline system, the first precursor is also chemically adsorbed onto the inner wall surface of the valve; in the step of introducing a second precursor into the transport pipeline system to form an anti-corrosion sub-coating, the second precursor also undergoes the self-limiting chemical reaction with the first precursor chemically adsorbed onto the inner wall surface of the valve, and the anti-corrosion sub-coating is also formed on the inner wall surface of the valve.

[0009] Optionally, the thickness of the anti-corrosion coating formed on the inner wall surface of the valve is less than the thickness of the anti-corrosion coating formed on the inner wall surface of the internal flow channel.

[0010] Optionally, the heating element includes one or more of a resistance heating band, a metal heating block, and a flexible heating garment.

[0011] Optionally, in the step of heating the pipeline to a deposition temperature between 50°C and 250°C.

[0012] Optionally, in the step of introducing the first precursor into the heated transport pipeline system, the first precursor is an aluminum-containing precursor or a silicon-containing precursor.

[0013] Optionally, the aluminum-containing precursor includes one or more of trimethylaluminum, aluminum trichloride, triethylaluminum, tripropoxyaluminum, tridiethylaminoaluminum, and triethanolamine; the silicon-containing precursor includes bis-tert-butylaminosilane, tri-tert-butoxysilanol, hexachlorosilane, tetramethylsilane, tetraethoxysilane, diisopropylaminosilane, and tridimethylaminosilane.

[0014] Optionally, in the step of introducing a second precursor into the transport pipeline system, the second precursor is an oxidizing agent or a nitriding agent.

[0015] Optionally, the oxidant includes one or more of water, hydrogen peroxide, ozone, nitrous oxide, oxygen free radicals, oxygen, and tert-butanol; the nitriding agent includes one or two of ammonia and nitrogen free radicals.

[0016] Optionally, the first inert gas includes one or both of argon and nitrogen; the second inert gas includes one or both of argon and nitrogen.

[0017] Optionally, the anti-corrosion coating is an oxide coating or a nitride coating.

[0018] Optionally, the oxide coating includes one or more of Al2O3, SiO2, Y2O3, HfO2, ZrO2, AlSiO, HfAlO, and HfZrO; the nitride coating includes one or two of SiN and SiON.

[0019] Optionally, the corrosive precursor used in the process includes one or more of molybdenum pentachloride, molybdenum tetrachloride, molybdenum hexachloride, molybdenum bromide, molybdenum iodide, and molybdenum fluoride.

[0020] Accordingly, embodiments of the present invention also provide a precursor delivery pipeline system for an atomic layer deposition (ALD) machine, including interconnected pipelines and a reaction chamber. The inner wall surfaces of the pipelines and the reaction chamber define an internal flow channel, and the inner wall surfaces defining the internal flow channel are deposited with an anti-corrosion coating formed by the deposition method provided by the present invention.

[0021] Accordingly, embodiments of the present invention also provide an atomic layer deposition apparatus, including a precursor delivery pipeline system. The precursor delivery pipeline system includes interconnected pipelines and a reaction chamber. The inner wall surfaces of the pipelines and the reaction chamber define internal flow channels. The inner wall surfaces defining the internal flow channels are deposited with an anti-corrosion coating formed by the deposition method provided by the present invention. Compared with the prior art, the technical solution of the embodiments of the present invention has the following advantages: The anti-corrosion coating deposition method provided in this invention allows deposition to be performed after the transport pipeline system is installed. This eliminates the need for disassembly and reinstallation of the transport pipeline system after the anti-corrosion coating is formed, thus eliminating mechanical damage to the inner wall surfaces of the pipeline and the reaction chamber caused by external forces. The anti-corrosion coating is formed before the initial introduction of the corrosive precursor for the process, ensuring that the precursor is immediately exposed to the complete anti-corrosion coating when it first flows through the internal channels. This avoids the pipeline substrate being exposed to corrosive media, improving the reliability of the precursor transport pipeline system in the atomic layer deposition system. A heating element located outside the pipeline heats the pipeline to the deposition temperature, providing heating conditions for depositing the anti-corrosion coating in the already installed state without relying on the reaction chamber. Furthermore, the temperature of the reaction chamber is set independently of the pipeline temperature via a temperature control unit. This allows the pipeline to reach the deposition temperature to meet the requirements of chemical adsorption and chemical reaction, while the reaction chamber can also be independently temperature-controlled according to its own conditions. The first precursor chemically adsorbs onto the inner wall surfaces of the pipeline and the reaction chamber, achieving self-limiting deposition. Chemical adsorption achieves full coverage of the surface defining the internal flow channels. After a first inert gas purging process removes unadsorbed substances and byproducts, a second precursor undergoes a self-limiting chemical reaction with the chemically adsorbed first precursor to form a single-layer anti-corrosion sub-coating. After a second inert gas purging process removes unreacted substances and byproducts, the active surface is exposed for subsequent cyclic adsorption. This process is repeated multiple times, with the anti-corrosion coating consisting of anti-corrosion sub-coatings formed in each deposition process. The preset thickness is controlled by the number of cycles, and the anti-corrosion coating, formed layer by layer, densely covers and defines the surface of the internal flow channels, preventing the penetration of the process corrosive precursor into the substrate. After the anti-corrosion coating reaches the preset thickness, a third purging process removes residues. The temperature of the transport pipeline system is then adjusted from the deposition temperature to the temperature for transporting the process corrosive precursor, allowing the transport pipeline system to transition directly from deposition conditions to process conditions without disassembly. This improves the reliability of the precursor transport pipeline system of the atomic layer deposition machine and the performance of the atomic layer deposition equipment. Attached Figure Description

[0022] Figure 1 This is a flowchart of the steps corresponding to an embodiment of the method for depositing an anti-corrosion coating on the inner wall of the precursor transport pipeline system of an atomic layer deposition machine according to the present invention; Figure 2 This is a flowchart of the steps corresponding to one embodiment of the film deposition process of the present invention; Figure 3 This is an experimental result diagram showing the analysis of the chlorine content on the surface of four different samples after performing the same corrosion test.

[0023] Figure 4This is a schematic diagram of a corresponding embodiment of the precursor delivery pipeline system for the atomic layer deposition machine of the present invention. Detailed Implementation

[0024] Currently, the reliability of the precursor transport pipeline system for atomic layer deposition (ALD) equipment and the performance of ALD equipment still need to be improved.

[0025] In traditional technologies, corrosion protection methods for precursor transport pipeline systems include: using 316L stainless steel electropolished pipelines that have undergone vacuum induction melting and vacuum arc remelting, utilizing the Cr2O3-rich passivation film formed on the inner wall surface of the pipeline to resist corrosion; electroplating high-phosphorus nickel on the inner wall surface of 316L stainless steel pipelines, utilizing the amorphous or microcrystalline structure of the high-phosphorus nickel plating to cut off the channels for chloride ions to penetrate along the grain boundaries; and using C22 Hastelloy pipelines, utilizing the high content of chromium, molybdenum, tungsten and other elements in the alloy to maintain an intact passivation film on the inner wall surface of the pipeline.

[0026] After the precursor transport pipeline system is treated with the above methods for corrosion protection, when transporting molybdenum halogen compounds, represented by molybdenum pentachloride, as corrosive precursors for process use, the protective layers of each of the above corrosion protection methods fail. As a result, the reliability of the precursor transport pipeline system of the atomic layer deposition machine and the performance of the atomic layer deposition equipment still need to be improved.

[0027] Specifically, for 316L stainless steel electropolished pipelines that have undergone vacuum induction melting and vacuum self-consumption remelting, the Cr2O3 passivation film formed on the inner wall surface has limited tolerance to chloride ions and is difficult to withstand for a long time in an environment containing high concentrations of chloride ions. Furthermore, molybdenum pentachloride releases highly active chloride ions during transportation, which damages the passivation film and makes the pipeline substrate easily exposed and corroded.

[0028] For the electroplating of high-phosphorus nickel on the inner wall of 316L stainless steel pipes, the pickling and activation process before electroplating will damage the original Cr2O3 passivation layer of 316L stainless steel. Furthermore, the high-phosphorus nickel plating inevitably contains micropores. In a high-purity gas environment, chloride ions may still penetrate into the substrate through these micropores. The substrate, now unprotected by the Cr2O3 passivation layer, is more susceptible to electrochemical corrosion, inducing the continuous release of nickel, iron, chromium, and other metal ions, causing process contamination. Simultaneously, when transporting molybdenum pentachloride, the strong chlorination property of molybdenum pentachloride will form a thin NiCl2 layer on the nickel surface, which will be reduced to nickel powder particles after migration and condensation. The phosphorus agglomeration in the high-phosphorus nickel plating forms a phosphorus-rich phase. The phosphorus in this phase reacts with molybdenum pentachloride to generate MoP and Mo3P nanoparticles. At the same time, nickel and molybdenum atoms interdiffusion occurs, precipitating metastable nickel-molybdenum alloy phase particles, leading to plating pulverization.

[0029] For C22 Hastelloy pipes, the dual corrosive properties of molybdenum pentachloride make it impossible to maintain passivation. On the one hand, molybdenum pentachloride is highly hygroscopic; even trace amounts of moisture in the environment can locally generate extremely high concentrations of hydrochloric acid on the inner surface of the C22 Hastelloy pipe. In this high-concentration hydrochloric acid, the C22 Hastelloy cannot maintain passivation and suffers severe corrosion. On the other hand, the molybdenum in molybdenum pentachloride is in the +5 valence state and has strong oxidizing properties. It will take electrons from the passivation film of the C22 Hastelloy, oxidizing the metallic molybdenum contained in the C22 Hastelloy itself into high-valence volatile molybdenum chloride compounds. Under this specific operating condition, the high molybdenum content becomes an active site for corrosion. In addition, C22 Hastelloy pipes are expensive.

[0030] To address the technical problem, this invention provides a method for depositing an anti-corrosion coating on the inner wall of a precursor transport pipeline system for an atomic layer deposition machine. The transport pipeline system includes interconnected pipes and a reaction chamber. The inner wall surfaces of the pipes and the reaction chamber define an internal flow channel, and the reaction chamber has a temperature control unit.

[0031] in, Figure 1 This is a flowchart of the steps corresponding to an embodiment of the method for depositing an anti-corrosion coating on the inner wall of the precursor transport pipeline system of an atomic layer deposition machine according to the present invention.

[0032] Step S1: With the transport pipeline system already installed and before the first introduction of the corrosive precursor for the process, the pipeline is heated to the deposition temperature using a heating element located outside the pipeline. Step S2: Repeatedly perform film deposition treatment on the inner wall surface of the internal flow channel multiple times to form an anti-corrosion coating until the thickness of the anti-corrosion coating reaches a preset thickness. The anti-corrosion coating is composed of anti-corrosion sub-coatings formed in each film deposition treatment. During the film deposition treatment, the temperature of the reaction chamber is set independently of the pipeline temperature by the temperature control unit. The film deposition treatment steps include: introducing a first precursor into the heated transport pipeline system, causing the first precursor to chemically adsorb onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber; and introducing a first inert gas into the transport pipeline system. The system undergoes a first purging treatment to remove unadsorbed first precursor and byproducts generated by chemisorption. After the first purging treatment, a second precursor is introduced into the transport pipeline system to allow the second precursor to undergo a self-limiting chemical reaction with the first precursor chemisorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming the anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. After the anti-corrosion sub-coating is formed, a second inert gas is introduced into the transport pipeline system for a second purging treatment to remove unreacted second precursor and byproducts generated by the self-limiting chemical reaction. Step S3: After the anti-corrosion coating reaches the preset thickness, the transport pipeline system is subjected to a third purging treatment; Step S4: After performing the third purging process, adjust the temperature of the transport pipeline system from the deposition temperature to the temperature used for transporting the corrosive precursor for the process.

[0033] The anti-corrosion coating deposition method provided in this invention allows deposition to be performed after the transport pipeline system is installed. This eliminates the need for disassembly and reinstallation of the transport pipeline system after the anti-corrosion coating is formed, thus eliminating mechanical damage to the inner wall surfaces of the pipeline and the reaction chamber caused by external forces. The anti-corrosion coating is formed before the initial introduction of the corrosive precursor for the process, ensuring that the precursor is immediately exposed to the complete anti-corrosion coating when it first flows through the internal channels. This avoids the pipeline substrate being exposed to corrosive media, improving the reliability of the precursor transport pipeline system in the atomic layer deposition system. A heating element located outside the pipeline heats the pipeline to the deposition temperature, providing heating conditions for depositing the anti-corrosion coating in the already installed state without relying on the reaction chamber. Furthermore, the temperature of the reaction chamber is set independently of the pipeline temperature via a temperature control unit. This allows the pipeline to reach the deposition temperature to meet the requirements of chemical adsorption and chemical reaction, while the reaction chamber can also be independently temperature-controlled according to its own conditions. The first precursor chemically adsorbs onto the inner wall surfaces of the pipeline and the reaction chamber, achieving self-limiting deposition. Chemical adsorption achieves full coverage of the surface defining the internal flow channels. After a first inert gas purging process removes unadsorbed substances and byproducts, a second precursor undergoes a self-limiting chemical reaction with the chemically adsorbed first precursor to form a single-layer anti-corrosion sub-coating. After a second inert gas purging process removes unreacted substances and byproducts, the active surface is exposed for subsequent cyclic adsorption. This process is repeated multiple times, with the anti-corrosion coating consisting of anti-corrosion sub-coatings formed in each deposition process. The preset thickness is controlled by the number of cycles, and the anti-corrosion coating, formed layer by layer, densely covers and defines the surface of the internal flow channels, preventing the penetration of the process corrosive precursor into the substrate. After the anti-corrosion coating reaches the preset thickness, a third purging process removes residues. The temperature of the transport pipeline system is then adjusted from the deposition temperature to the temperature for transporting the process corrosive precursor, allowing the transport pipeline system to transition directly from deposition conditions to process conditions without disassembly. This improves the reliability of the precursor transport pipeline system of the atomic layer deposition machine and the performance of the atomic layer deposition equipment.

[0034] To make the above-mentioned objects, features and advantages of the embodiments of the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0035] The following is the specific content of the first embodiment.

[0036] The precursor transport piping system of an atomic layer deposition (ALD) machine is used to transport process-grade corrosive precursors from multiple precursor sources of the ALD machine to the reaction chamber for performing the ALD process within the reaction chamber.

[0037] During the transport process, the corrosive precursors flow through the internal channels of the transport pipeline system and come into direct contact with the inner wall surface of the internal channels. If the inner wall surface lacks effective anti-corrosion protection, the corrosive precursors will corrode the matrix material on the inner wall surface, which will not only damage the transport pipeline system itself, but also introduce metal contamination into the high-purity process, reducing the reliability of the atomic layer deposition process and the service life of the atomic layer deposition equipment.

[0038] In this embodiment, the transport pipeline system includes interconnected pipelines and a reaction chamber. The inner wall surfaces of the pipelines and the reaction chamber define an internal flow channel, and the reaction chamber has a temperature control unit.

[0039] The pipeline is a transport channel for corrosive precursors used in the process, and the reaction chamber is a container for performing atomic layer deposition reactions.

[0040] The internal flow channel is the entire space through which the corrosive precursor for the process flows from the pipeline to the reaction chamber, and its boundary is defined by the inner wall surfaces of the pipeline and the reaction chamber. Since the internal flow channel is defined by these surfaces, the integrity of the inner wall surfaces directly determines whether the corrosive precursor comes into contact with any exposed substrate material during transport. Therefore, an anti-corrosion coating is required to cover the entire inner wall surface of the internal flow channel to block the penetration path of the corrosive precursor into the substrate.

[0041] It should be noted that the temperature control unit is a device used to independently set and control the temperature of the reaction chamber, and is independent of the heating components used to heat the pipeline. The existence of the temperature control unit allows the temperature of the reaction chamber to be set and adjusted independently of the pipeline temperature, providing a hardware basis for temperature decoupling between the pipeline and the reaction chamber when the anti-corrosion coating is deposited in the subsequent installed state of the transport pipeline system.

[0042] In this embodiment, the pipeline has a valve mounting position.

[0043] Specifically, a valve mounting position is a pre-reserved interface location on a pipeline for installing a valve. When a valve is installed in its mounting position, the inner wall surface of the valve also forms part of the boundary of the internal flow channel, and corrosive process precursors will also come into contact with the inner wall surface of the valve as they flow through it. When the valve is not installed, the valve mounting position can be sealed with a blind flange to maintain the continuity and sealing of the internal flow channel.

[0044] The first embodiment is illustrated by taking the example of sealing the valve mounting position with a blind flange when the valve is not installed.

[0045] Perform step S11: Seal the valve mounting position with a blind flange.

[0046] It should be noted that the valve mounting position is sealed with a blind flange to maintain the continuity and sealing of the internal flow channel.

[0047] Step S1: With the transport pipeline system already installed and before the first introduction of the corrosive precursor for the process, the pipeline is heated to the deposition temperature using a heating element located outside the pipeline.

[0048] It should be noted that the state in which the transport pipeline system is installed means that the pipelines and reaction chambers constituting the transport pipeline system have completed physical connection and sealing assembly with each other, and are in the same installation configuration as when the transport pipeline system is working normally.

[0049] It should also be noted that performing the anti-corrosion coating deposition under this condition means that the anti-corrosion coating formed by the subsequent film deposition process does not need to undergo disassembly and reinstallation. This eliminates the risk of mechanical damage to the inner wall surface of the pipeline and the inner wall surface of the reaction chamber caused by stress and compression during pipeline disassembly, transportation and reinstallation.

[0050] Performing step S1 before the first introduction of the corrosive precursor for the process means that when the corrosive precursor for the process first flows through the internal flow channel, the inner wall surface of the pipe defining the internal flow channel and the inner wall surface of the reaction chamber are completely covered by the anti-corrosion coating. The corrosive precursor for the process will not come into direct contact with the base material of the pipe or the reaction chamber, thus avoiding the corrosion risk caused by the exposed base material of the pipe and the reaction chamber coming into contact with the corrosive precursor.

[0051] Specifically, by using heating components located outside the pipeline, the pipeline is heated to the deposition temperature, providing a heating basis for in-situ deposition of anti-corrosion coatings in the pipeline system after installation. Since the pipeline system has been installed, the pipeline cannot be placed in a separate deposition chamber for heating. The heating components located outside the pipeline directly heat the pipeline, enabling the pipeline to reach the deposition temperature in the installed state.

[0052] The phrase "heating components are located outside the pipeline" means that the heating components are in contact with or surround the outer wall of the pipeline, and transfer heat to the pipeline through heat conduction or heat radiation.

[0053] In this embodiment, the heating component includes one or more of a resistance heating band, a metal heating block, and a flexible heating garment.

[0054] It should be noted that during the step of heating the pipeline to the deposition temperature, the deposition temperature should not be too high or too low. If the deposition temperature is too low, during the subsequent introduction of the first and second precursors, the temperature of the inner wall surfaces of the pipeline and the reaction chamber will be lower than the lower limit of the temperature required for the self-limiting chemical reaction of the first and second precursors. This will result in insufficient chemisorption rates, and the first precursor will not reach saturation adsorption on the inner wall surfaces of the pipeline and the reaction chamber. This will lead to incomplete anti-corrosion coatings, with uncovered areas on the inner wall surfaces of the pipeline and the reaction chamber. The corrosive precursor used in the process can then penetrate into the substrate through these uncovered areas, affecting the reliability of the precursor transport pipeline system and the performance of the atomic layer deposition equipment. If the deposition temperature is too low... If the temperature is too high, during the subsequent introduction of the first and second precursors, the temperature of the inner wall surfaces of the pipeline and reaction chamber will exceed the upper temperature limit required for the first and second precursors to undergo self-limiting chemical reactions. This significantly increases the probability of gas-phase decomposition of the first and second precursors before they reach the inner wall surfaces of the pipeline and reaction chamber. The resulting decomposition products are deposited on the inner wall surfaces of the pipeline and reaction chamber in a non-self-limiting manner, leading to uneven thickness and reduced density of the formed anti-corrosion sub-coating. This negates the self-limiting growth advantage of atomic layer deposition, affecting the reliability of the precursor transport pipeline system and the performance of the atomic layer deposition equipment. Therefore, in this embodiment, in the step of heating the pipeline to the deposition temperature, the deposition temperature is between 50°C and 250°C.

[0055] In this embodiment, the corrosive precursor used in the process includes one or more of molybdenum pentachloride, molybdenum tetrachloride, molybdenum hexachloride, molybdenum bromide, molybdenum iodide, and molybdenum fluoride.

[0056] Molybdenum pentachloride, molybdenum tetrachloride, molybdenum hexachloride, molybdenum bromide, molybdenum iodide, and molybdenum fluoride are all molybdenum halogen compounds. They are used as molybdenum source precursors in atomic layer deposition processes and also have the aforementioned heavy corrosion characteristics. The anti-corrosion coating deposited by the anti-corrosion coating deposition method provided by the present invention is used to protect the inner wall surface of the internal flow channel when these molybdenum halogen compounds flow through the internal flow channel.

[0057] Step S2: Repeatedly perform film deposition treatment on the inner wall surface of the internal flow channel multiple times to form an anti-corrosion coating until the thickness of the anti-corrosion coating reaches a preset thickness. The anti-corrosion coating is composed of anti-corrosion sub-coatings formed in each film deposition treatment. During the film deposition treatment, the temperature of the reaction chamber is set independently of the temperature of the pipeline by the temperature control unit.

[0058] Specifically, the inner wall surface of the internal flow channel undergoes multiple film deposition processes, and the anti-corrosion coating is composed of anti-corrosion sub-coatings formed in each film deposition process. That is, each film deposition process forms only one anti-corrosion sub-coating. The thickness of the anti-corrosion sub-coating is determined by the chemisorption saturation of the first precursor and the degree of completion of the self-limiting chemical reaction between the second precursor and the chemisorbed first precursor in each film deposition process. This ensures that the thickness of the anti-corrosion sub-coating formed in a single film deposition process is fixed. By controlling the number of repetitions of the film deposition process, the final thickness of the anti-corrosion coating can be precisely controlled, ensuring that the anti-corrosion coating reaches the preset thickness.

[0059] It should be noted that the anti-corrosion coating formed by repeatedly performing multiple film deposition processes and stacking layers has the inherent density of atomic layer deposition technology. The interfaces between the multiple anti-corrosion sub-coatings are continuous and free of pinholes, which can effectively prevent the corrosive precursors used in the process from penetrating into the substrate on the inner wall surface of the internal flow channel and the inner wall surface of the reaction chamber.

[0060] The preset thickness refers to the minimum thickness that the anti-corrosion coating needs to achieve to meet the anti-corrosion protection requirements of the inner wall surface of the internal flow channel and the inner wall surface of the reaction chamber.

[0061] Specifically, the preset thickness needs to be large enough to ensure that the anti-corrosion coating forms a continuous and dense cover layer, eliminating leakage channels through which corrosive precursors can directly penetrate into the substrate. If the film deposition process is stopped before the preset thickness is reached, the anti-corrosion coating may not have formed a continuous and dense cover, allowing corrosive precursors to penetrate into the substrate surface through uncovered gaps, leading to localized corrosion. Repeating the film deposition process multiple times until the preset thickness is reached ensures that the anti-corrosion coating achieves sufficient coverage on the inner walls of the internal flow channels and the reaction chamber, providing reliable corrosion protection for the transport pipeline system.

[0062] In this embodiment, the temperature of the reaction chamber is set independently of the pipeline temperature by a temperature control unit.

[0063] As mentioned earlier, the reaction chamber has a temperature control unit, and the pipeline is heated by a heating element located outside the pipeline. The heating systems of the two are independent of each other.

[0064] As an example, the temperature of the reaction chamber is 300°C.

[0065] Specifically, after the first precursor is introduced, it first flows over the inner wall surface of the pipeline, and then gradually flows along the extension direction of the internal flow channel to the inner wall surface of the reaction chamber. That is to say, the inner wall surface of the pipeline is upstream in the flow path of the first precursor, and the inner wall surface of the reaction chamber is downstream. When the first precursor flows over the inner wall surface of the pipeline, the inner wall surface of the pipeline has already been heated to the deposition temperature by the heating element located outside the pipeline in step S1. The first precursor obtains surface temperature conditions matching the deposition temperature when it first contacts the inner wall surface of the pipeline, so that it can fully chemically adsorb and reach saturation on the inner wall surface of the pipeline.

[0066] However, the inner wall surface of the reaction chamber is downstream of the inner wall surface of the pipeline within the internal flow channel. The first precursor has already flowed through the entire pipeline heated to the deposition temperature before reaching the inner wall surface of the reaction chamber, thus the pipeline preheats the first precursor. During its flow through the pipeline, the first precursor undergoes sufficient chemical adsorption with the inner wall surface, and its own temperature approaches the deposition temperature of the pipeline. When the first precursor reaches the inner wall surface of the reaction chamber, the heat carried by the first precursor creates an airflow heating effect on the inner wall surface. Furthermore, the inner wall surface of the reaction chamber is relatively far from the heating element located outside the pipeline, and the heating effect of the heating element on the inner wall surface of the reaction chamber through heat conduction from the pipeline wall decreases with increasing distance. Under the combined effect of these two factors, the inner wall surface of the reaction chamber does not need to be heated to the same deposition temperature as the pipeline for the first precursor to undergo sufficient chemical adsorption upon reaching it.

[0067] This means that in this embodiment, the temperature of the reaction chamber is set independently of the pipeline temperature via a temperature control unit. Heating the pipeline to the deposition temperature ensures the saturation of chemisorption of the first precursor on the inner wall surface of the upstream pipeline, and the sufficient degree of self-limiting chemical reaction between the second precursor and the first precursor already chemisorbed on the inner wall surface of the pipeline. The temperature of the reaction chamber is set independently according to its own conditions via the temperature control unit, without needing to heat the reaction chamber to the same temperature as the pipeline to match its deposition temperature. Thus, the pipeline and the reaction chamber each maintain their required temperature conditions during the film deposition process, allowing the first precursor to undergo sufficient chemisorption on the inner wall surface of the pipeline as it flows through, and enabling the second precursor to undergo sufficient self-limiting chemical reaction with the first precursor already chemisorbed on the inner wall surface of the pipeline. Correspondingly, the temperature of the reaction chamber is set independently of the pipeline temperature by the temperature control unit, which also allows the first precursor to undergo sufficient chemical adsorption on the inner wall surface of the reaction chamber when it flows through the reaction chamber, and the second precursor to undergo sufficient self-limiting chemical reaction with the first precursor that has been chemically adsorbed on the inner wall surface of the reaction chamber.

[0068] Specifically, the steps of the film deposition process are described in detail. Figure 2 This is a flowchart of the steps corresponding to the first embodiment of the film deposition process of the present invention.

[0069] Step S21: Introduce the first precursor into the heated transport pipeline system, so that the first precursor is chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber.

[0070] It should be noted that the first precursor is introduced into the internal flow channel of the heated transport pipeline system in gaseous form. During the process of flowing through the internal flow channel, the first precursor comes into contact with the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, and undergoes chemical adsorption.

[0071] It should also be noted that chemisorption refers to the chemical reaction between the first precursor molecule and the active groups (such as hydroxyl groups) on the inner wall surfaces of the pipeline and the reaction chamber, forming chemical bonds and thus fixing the first precursor molecule to these surfaces. Due to the self-limiting nature of chemisorption, once all active sites on the inner wall surfaces of the pipeline and the reaction chamber are occupied by the first precursor molecule, the chemisorption of the first precursor molecule automatically stops, and subsequent introduction of the first precursor molecule will not undergo chemisorption. This self-limiting chemisorption ensures that the adsorption amount of the first precursor on the inner wall surfaces of the pipeline and the reaction chamber is on the order of a monolayer, with uniform adsorption thickness independent of the flow channel geometry. Regardless of whether the pipeline is a straight section or a bend, and regardless of whether the inner wall surface of the pipeline is flat or curved, the inner wall surfaces of all pipelines defining the internal flow channels and the inner wall surfaces of the reaction chamber can obtain a first precursor chemical adsorption layer of the same thickness. This lays the technological foundation for the subsequent introduction of a second precursor to undergo a self-limiting chemical reaction with the chemically adsorbed first precursor to form a uniformly thick anti-corrosion sub-coating.

[0072] As an example, the pipeline system is made of 316 stainless steel.

[0073] Specifically, the inner wall surface of the 316 stainless steel substrate has oxides of chromium oxide, iron oxide, or other alloying elements. These oxides naturally absorb moisture in the air, thereby forming hydroxyl active groups on the inner wall surface of the 316 stainless steel substrate. This allows the first precursor molecules to chemically react with the active groups (such as hydroxyl groups) on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming chemical bonds.

[0074] In this embodiment, the first precursor is an aluminum-containing precursor or a silicon-containing precursor.

[0075] It should be noted that the oxide coating formed after the aluminum-containing precursor undergoes a self-limiting chemical reaction with the oxidant is an alumina coating. The alumina coating is composed of aluminum oxide ion-covalent bonds, exhibiting high hardness and strong resistance to chloride ion diffusion. For pipeline systems transporting molybdenum halogen compounds such as molybdenum pentachloride, the alumina coating demonstrates high chemical stability in environments with high chloride ion concentrations, effectively preventing chloride ions from penetrating along coating grain boundaries or defects into the substrate on the inner surfaces of pipelines, valves, and reaction chambers.

[0076] It should also be noted that the oxide coating formed by the self-limiting chemical reaction between the silicon-containing precursor and the oxidant is a silicon oxide coating, and the nitride coating formed by the self-limiting chemical reaction with the nitriding agent is a silicon nitride coating. Silicon oxide coatings exhibit extremely high chemical inertness when faced with the high concentration of hydrochloric acid generated from the hydrolysis of corrosive process precursors; hydrogen ions and chloride ions have difficulty penetrating the silicon-oxygen network structure to reach the substrate surface.

[0077] Specifically, the aluminum-containing precursor includes one or more of trimethylaluminum, aluminum trichloride, triethylaluminum, tripropoxyaluminum, tridiethylaminoaluminum, and aluminum triethanolamine. Trimethylaluminum, aluminum trichloride, triethylaluminum, tripropoxyaluminum, tridiethylaminoaluminum, and aluminum triethanolamine all contain aluminum. Under appropriate deposition temperatures, the aluminum-containing precursor can chemically adsorb onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, serving as the aluminum source for forming the aluminum-containing anti-corrosion coating.

[0078] Specifically, the silicon-containing precursor includes one or more of bis-tert-butylaminosilane, tri-tert-butoxysilanol, hexachloroethylsilane, tetramethylsilane, tetraethoxysilane, diisopropylaminosilane, and tridimethylaminosilane. Bis-tert-butylaminosilane, tri-tert-butoxysilanol, hexachloroethylsilane, tetramethylsilane, tetraethoxysilane, diisopropylaminosilane, and tridimethylaminosilane all contain silicon. At appropriate deposition temperatures, the silicon-containing precursor can chemically adsorb onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, serving as a silicon source for forming a silicon-containing anti-corrosion coating.

[0079] Step S22: Introduce a first inert gas into the transport pipeline system to perform a first purging treatment to remove the unadsorbed first precursor and the byproducts generated by the chemical adsorption.

[0080] It should be noted that in step S21, after the first precursor is introduced, the internal flow channel simultaneously contains the first precursor that has been chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, the free first precursor that has not undergone chemical adsorption, and byproducts generated when the first precursor reacts with the active groups on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber through chemical adsorption. If the free first precursor and the byproducts generated by chemical adsorption are not removed before the second precursor is introduced, the free first precursor will react directly with the second precursor in the gas phase space of the internal flow channel to generate particulate byproducts. These particulate byproducts will deposit on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, damaging the density and uniformity of the anti-corrosion coating.

[0081] It should also be noted that the first purging process is used to remove the unadsorbed first precursor and the byproducts generated by chemisorption from the internal flow channel, leaving only the first precursor molecular layer that has been chemisorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, so as to provide a clean reaction interface for the subsequent self-limiting chemical reaction between the second precursor and the chemisorbed first precursor.

[0082] In this embodiment, the first inert gas includes one or both of argon and nitrogen.

[0083] Specifically, argon has high chemical inertness, resulting in a good physical scouring effect on the inner wall surface of the internal flow channel during the first purging process; nitrogen has high chemical inertness and low acquisition cost. Therefore, argon or nitrogen, or a mixture of argon and nitrogen, can be selected as the first inert gas according to the deposition process requirements. Both can effectively remove unadsorbed first precursors and byproducts generated by chemical adsorption, and the first inert gas itself does not chemically react with the first precursors already chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber.

[0084] Step S23: After the first purging treatment, a second precursor is introduced into the transport pipeline system so that the second precursor undergoes a self-limiting chemical reaction with the first precursor chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming the anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber.

[0085] Specifically, after the first purging process, only the chemically adsorbed first precursor molecular layer remains on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. At this time, the second precursor is introduced, and the second precursor undergoes a self-limiting chemical reaction with the first precursor that has been chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber.

[0086] It should be noted that the self-limiting chemical reaction refers to the second precursor reacting only with the groups of the chemically adsorbed first precursor, forming an anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. The self-limiting chemical reaction automatically terminates after consuming all the active sites of the chemically adsorbed first precursor, and the excess second precursor no longer reacts. In other words, the self-limiting chemical reaction ensures that the thickness of the anti-corrosion sub-coating is determined only by the amount of chemically adsorbed first precursor, and is not affected by the amount or time of introduction of the second precursor, thus achieving precise control over the thickness of the anti-corrosion sub-coating.

[0087] In this embodiment, the second precursor is an oxidizing agent or a nitriding agent.

[0088] Specifically, when the second precursor is an oxidant, the oxidant reacts with the first precursor, which has been chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, to form an anti-corrosion sub-coating, which is an oxide coating; when the second precursor is a nitriding agent, the nitriding agent reacts with the first precursor, which has been chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, to form an anti-corrosion sub-coating, which is a nitride coating.

[0089] It should be noted that the oxidant includes one or more of water, hydrogen peroxide, ozone, nitrous oxide, oxygen free radicals, oxygen, and tert-butanol. At an appropriate deposition temperature, the above-mentioned oxidant can fully react with the first precursor, which has been chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, converting the metal or silicon elements in the first precursor into corresponding oxides.

[0090] It should be noted that the nitriding agent includes one or both of ammonia and nitrogen free radicals. Ammonia can undergo a nitriding reaction with the first precursor that has been chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber at an appropriate deposition temperature, converting the silicon element in the first precursor into silicon nitride; nitrogen free radicals have higher reactivity and can achieve the nitriding reaction at a lower deposition temperature.

[0091] In this embodiment, the anti-corrosion coating is an oxide coating or a nitride coating.

[0092] Specifically, the oxide coating is composed of metal or silicon elements and oxygen elements through ionic-covalent mixed bonds. These chemical bonds have high bond energies, preventing bond breakage or recombination when the oxide coating comes into contact with corrosive precursors used in the process, thus exhibiting high chemical inertness. For pipeline systems transporting molybdenum halogen compounds, the corrosive precursors possess both reducing acidic corrosion (resulting in hydrochloric acid) and oxidizing corrosion (resulting in electron capture by high-valence molybdenum ions). The metal-oxygen or silicon-oxygen bonds in the oxide coating do not dissolve or undergo ion exchange reactions with hydrogen and chloride ions in hydrochloric acid, and do not donate electrons to high-valence molybdenum ions. Therefore, the oxide coating can completely isolate the corrosive precursors from the substrate of the inner surfaces of pipelines, valves, and reaction chambers.

[0093] It should be noted that nitride coatings are composed of silicon and nitrogen elements connected by a covalent bond network. The high density of these covalent bonds results in a dense nitride coating structure with no microscopic channels for chloride ions to penetrate. Compared to oxide coatings, the bonds between nitrogen and silicon atoms in nitride coatings are more tightly bound, providing stronger resistance to chloride ion diffusion.

[0094] In this embodiment, the oxide coating includes one or more of Al2O3, SiO2, Y2O3, HfO2, ZrO2, AlSiO, HfAlO, and HfZrO.

[0095] It should be noted that the above oxide coating is composed of strong ionic-covalent mixed bonds, which has the characteristics of high thermodynamic stability and strong chemical inertness in chlorine-containing environments. It can effectively prevent the penetration of corrosive precursors used in the process into the substrate on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber.

[0096] In this embodiment, the nitride coating includes one or both of SiN and SiON.

[0097] Specifically, SiN has excellent ability to block the diffusion of chloride ions; SiON combines the high density of silicon nitride and the high chemical inertness of silicon oxide.

[0098] Step S24: After the anti-corrosion sub-coating is formed, a second inert gas is introduced into the transport pipeline system for a second purging treatment to remove unreacted second precursor and byproducts generated by the self-limiting chemical reaction.

[0099] In step S23, after the self-limiting chemical reaction is completed, the internal flow channel simultaneously contains the generated anti-corrosion sub-coating, the unreacted second precursor, and the byproducts of the self-limiting chemical reaction. If the unreacted second precursor and the byproducts of the self-limiting chemical reaction are not removed before proceeding to the next film deposition process, the remaining second precursor will react directly with the first precursor introduced in the next film deposition process in the gas phase space of the internal flow channel, similarly generating particulate byproducts and damaging the quality of the subsequent anti-corrosion sub-coating.

[0100] It should be noted that the second purging process removes the unreacted second precursor and the byproducts generated by the self-limiting chemical reaction from the internal flow channel, while exposing the active sites on the surface of the anti-corrosion sub-coating. This restores the inner wall surface of the pipeline and the inner wall surface of the reaction chamber to an active surface that can be chemically adsorbed by the first precursor in the next film deposition process.

[0101] In this embodiment, the second inert gas includes one or both of argon and nitrogen.

[0102] Specifically, the second inert gas can be the same as or a different type of gas from the first inert gas. Argon has high chemical inertness, resulting in a good physical scouring effect on the inner wall surface of the internal flow channel during the second purging process. Nitrogen has high chemical inertness and low acquisition cost. Therefore, argon or nitrogen, or a mixture of argon and nitrogen, can be selected as the second inert gas according to the deposition process requirements. Both can effectively remove unadsorbed second precursors and byproducts generated by chemical adsorption, and the second inert gas itself does not chemically react with the already formed anti-corrosion sub-coating.

[0103] It should be noted that steps S21 to S24 are repeated, and each execution constitutes a film deposition process. Anti-corrosion sub-coatings are formed layer by layer on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber until the total thickness of the anti-corrosion coating reaches the preset thickness.

[0104] It should also be noted that the number of repetitions is determined based on the ratio between the preset thickness and the thickness of the anti-corrosion sub-coating formed in a single film deposition process. Since the thickness of the anti-corrosion sub-coating formed in each film deposition process is fixed, precise control of the preset thickness can be achieved by controlling the number of repetitions.

[0105] In one specific embodiment, the first precursor is trimethylaluminum, the second precursor is water, the deposition temperature is 200°C, and both the first and second inert gases are argon. Trimethylaluminum, as the first precursor, is introduced into the internal flow channel of a transport pipeline system heated to 200°C. The reaction chamber temperature is 300°C. Trimethylaluminum is chemically adsorbed onto the inner wall surfaces of the pipeline and the reaction chamber. After a first purging treatment using argon as the first inert gas, water, as the second precursor, is introduced. The water undergoes a self-limiting chemical reaction with the trimethylaluminum already chemically adsorbed onto the inner wall surfaces of the pipeline and the reaction chamber, forming an alumina anti-corrosion sub-coating on the inner wall surfaces of the pipeline and the reaction chamber. A second purging treatment is then performed using argon as the second inert gas. The above film deposition process is repeated until the thickness of the alumina anti-corrosion coating reaches a preset thickness, which is 10 nanometers.

[0106] Alumina coatings are characterized by high hardness, good density, and excellent corrosion resistance, effectively preventing chloride ions in corrosive process precursors from penetrating into the substrate of pipelines and reaction chambers.

[0107] In another specific embodiment, the first precursor is diisopropylaminosilane, the second precursor is ozone, the deposition temperature is 150°C, and both the first and second inert gases are nitrogen. Diisopropylaminosilane, as the first precursor, is introduced into the internal flow channel of a transport pipeline system heated to 150°C. The reaction chamber temperature is 250°C. Diisopropylaminosilane is chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. After a first purging treatment using nitrogen as the first inert gas, ozone, as the second precursor, is introduced. The ozone reacts with the diisopropylaminosilane already chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber in a self-limiting chemical reaction, forming a silicon oxide anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. The film deposition process is repeated until the thickness of the silicon oxide anti-corrosion sub-coating reaches a preset thickness, which is 10 nanometers.

[0108] The silica coating has extremely high chemical inertness in acidic environments and can effectively block the penetration of hydrogen and chloride ions when faced with high concentrations of hydrochloric acid generated by the hydrolysis of corrosive process precursors.

[0109] Step S3: After the anti-corrosion coating reaches the preset thickness, the transport pipeline system is subjected to a third purging treatment.

[0110] Specifically, the third purging process is used to remove any unadsorbed first precursor, unreacted second precursor, and byproducts generated in each reaction step from the internal flow channel. The third purging process is the final purging performed after the anti-corrosion coating has reached the preset thickness and the film deposition process is no longer performed. Its purging time can be longer than that of the first and second purging processes to ensure that the anti-corrosion coating surface formed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber is clean and free of any residue.

[0111] In this embodiment, the inert gas used in the third purging process can be the same as the first inert gas or the second inert gas.

[0112] Step S31: Remove the blind flange; install the valve at the valve mounting position; perform the film deposition treatment step again on the transport pipeline system after the valve is installed to form the anti-corrosion coating on the inner wall surface of the valve.

[0113] As mentioned earlier, the pipeline has valve mounting positions. Before the anti-corrosion coating is deposited, the valve mounting positions are sealed by blind flanges. By sealing the valve mounting positions with blind flanges, the first and second precursors will not leak from the valve mounting positions when flowing through the internal channels during the film deposition process, thus ensuring the sealing of the internal channels and the integrity of the flow paths of the first and second precursors.

[0114] It should be noted that during steps S1 and S2 of the film deposition process on the transport pipeline system with the valve mounting position sealed by a blind flange, the first precursor is chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming an anti-corrosion sub-coating that covers the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. The valve mounting position is sealed by a blind flange, and an anti-corrosion sub-coating is also deposited on the surface of the blind flange, but the valve has not yet been installed, so the inner wall surface of the valve has not yet been covered by the anti-corrosion coating.

[0115] It should also be noted that after the anti-corrosion coating of a preset thickness has been formed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, the blind flange is removed, and the valve is installed at the valve mounting position. After the valve is installed, the boundary of the internal flow channel of the pipeline system changes, that is, the inner wall surface of the valve becomes part of the inner wall surface that defines the internal flow channel. However, the inner wall surface of the valve has not yet been covered by the anti-corrosion coating. Therefore, it is necessary to perform a film deposition treatment on the pipeline system after the valve is installed, so that the first precursor is still chemically adsorbed on the inner wall surface of the valve, and the second precursor also undergoes a self-limiting chemical reaction with the first precursor that has been chemically adsorbed on the inner wall surface of the valve. The anti-corrosion sub-coating is also formed on the inner wall surface of the valve, so that the inner wall surface of the valve is also protected by the anti-corrosion coating.

[0116] As an example, in the step of performing a film deposition treatment on the pipeline system after valve installation, the first precursor is trimethylaluminum, the second precursor is water, the deposition temperature is 200°C, and both the first and second inert gases are nitrogen. Trimethylaluminum, as the first precursor, is introduced into the internal flow channel of the pipeline system heated to 200°C, and the temperature of the reaction chamber is 300°C. Trimethylaluminum is chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. After a first purging treatment using nitrogen as the first inert gas, water, as the second precursor, is introduced. The water undergoes a self-limiting chemical reaction with the trimethylaluminum already chemically adsorbed onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming an alumina anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. A second purging treatment is then performed using nitrogen as the second inert gas. Repeat the above film deposition process until the thickness of the alumina anti-corrosion coating on the inner wall surface of the valve reaches the preset thickness, which is 10 nanometers.

[0117] Specifically, in step S31, when the pipeline system after valve installation is subjected to film deposition again, the inner wall surface of the pipeline and the inner wall surface of the reaction chamber have already formed an anti-corrosion coating of a preset thickness in the previous step S2. Performing film deposition again will cause the anti-corrosion sub-coating to be superimposed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, so that the total thickness of the anti-corrosion coating formed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber exceeds the preset thickness originally achieved in step S2. This increase in thickness will not adversely affect the performance of the anti-corrosion coating, and can further reduce the risk of corrosion of the substrate of the pipeline and the reaction chamber when the corrosive precursor of the process flows through the internal flow channel for the first time, and further improve the reliability of the precursor transport pipeline system of the atomic layer deposition machine.

[0118] In this embodiment, the thickness of the anti-corrosion coating formed on the inner wall surface of the valve is less than the thickness of the anti-corrosion coating formed on the inner wall surface of the internal flow channel.

[0119] It should be noted that valves are moving parts, and their inner surfaces include the valve cavity wall and the valve core's moving contact surface. If the anti-corrosion coating on the valve's inner surface is too thick, it may affect the flexibility of the valve's opening and closing actions as well as its sealing performance. Pipelines and reaction chambers, on the other hand, are stationary parts, and there is no need to consider motion interference caused by coating thickness. The anti-corrosion coating on the inner surfaces of pipelines and reaction chambers can be of greater thickness to provide a more ample margin of corrosion protection.

[0120] Step S4: After performing the third purging process, adjust the temperature of the transport pipeline system from the deposition temperature to the temperature used for transporting the corrosive precursor for the process.

[0121] Specifically, after the anti-corrosion coating reaches the preset thickness and undergoes the third purging treatment, the transport pipeline system no longer performs film deposition treatment and needs to switch from deposition mode to process mode to prepare to receive the corrosive precursor for the process to perform atomic layer deposition.

[0122] It should be noted that adjusting the temperature of the transport pipeline system from the deposition temperature to the temperature required for transporting corrosive precursors for the process refers to adjusting the pipeline temperature from the uniform deposition temperature under deposition conditions to the temperature required for transporting corrosive precursors under process conditions. This temperature adjustment step completes a smooth transition of the transport pipeline system from deposition conditions to process conditions, allowing the transport pipeline system to directly enter the working state after installation, without disassembling or modifying any connections to receive corrosive precursors for the process.

[0123] To verify the corrosion resistance of the anti-corrosion coating formed by the present invention, this embodiment uses an alumina (Al2O3) coating as an example of the present invention.

[0124] Using trimethylaluminum as the first precursor and water as the second precursor, a deposition temperature of 200°C and a reaction chamber temperature of 200°C were used, and the number of cycles was 200 to form an alumina coating with a thickness of about 20 nm on the inner wall surface of the transport pipeline system.

[0125] Using C22 Hastelloy, 316 stainless steel, and high-phosphorus nickel as the base materials of the transport pipeline systems for comparison, the same corrosion tests were performed on the four transport pipeline systems respectively.

[0126] The corrosion test method is as follows: four types of pipeline systems are placed in a molybdenum pentachloride (MoCl5) vapor environment at a process temperature of 160℃ and a pressure of 20 Torr, with molybdenum pentachloride and nitrogen gas alternately introduced for 1200 cycles.

[0127] After testing, SEM was used to observe the surface morphology of the samples, and EDS was used to analyze the chlorine content on the inner wall surface of the four transport pipeline systems. The test results are as follows: Figure 3 As shown.

[0128] Figure 3 The third line in the diagram illustrates the EDS analysis results: the alumina coating deposited on the inner wall of the pipeline system using the method of this invention showed no chlorine content detected on the surface after corrosion testing, indicating a chlorine content of 0%; while for comparison, the chlorine content on the surface of the other three pipeline systems was 0.4% for high-phosphorus nickel, 1.8% for C22 Hastelloy, and 12.8% for 316 stainless steel.

[0129] The above test results show that no chlorine element was detected on the surface of the alumina anti-corrosion coating formed by the present invention. The alumina anti-corrosion coating has a significantly better ability to block chloride ions than high phosphorus nickel, C22 Hastelloy and 316 stainless steel substrates. It can effectively resist the penetration of chloride ions released by corrosive process precursors such as molybdenum pentachloride, and significantly improve the corrosion resistance of the precursor transport pipeline system.

[0130] The following is the specific content of the second embodiment.

[0131] The similarities between the second embodiment and the first embodiment will not be repeated here. The differences between the second embodiment and the first embodiment are as follows: The pipeline has a valve mounting position, and the transport pipeline system also includes a valve installed at the valve mounting position, and the internal flow channel is further defined by the inner wall surface of the valve.

[0132] It should be noted that the valve is already installed in the valve mounting position before the anti-corrosion coating is deposited, so there is no need to seal the valve mounting position with a blind flange.

[0133] The second embodiment is illustrated using the example of a valve already installed in its mounting position.

[0134] In this embodiment, during the step of introducing the first precursor into the heated transport pipeline system, the first precursor is also chemically adsorbed onto the inner wall surface of the valve.

[0135] Specifically, during the flow of the first precursor through the internal channel, it is simultaneously chemically adsorbed onto the inner wall surfaces of the pipeline, valve, and reaction chamber. All inner wall surfaces of the internal channel acquire an equal amount of the first precursor chemically adsorbed layer during the introduction of the first precursor. Due to the self-limiting nature of chemical adsorption, once all active sites on the inner wall surfaces of the pipeline, valve, and reaction chamber are occupied by the first precursor molecules, the chemical adsorption of the first precursor molecules automatically stops. Subsequent introductions of the first precursor molecules will no longer undergo chemical adsorption. This lays the technological foundation for the subsequent introduction of the second precursor to undergo a self-limiting chemical reaction with the first precursor already chemically adsorbed on the inner wall surface of the valve, forming a uniformly thick anti-corrosion sub-coating.

[0136] In this embodiment, during the step of introducing a second precursor into the transport pipeline system to form an anti-corrosion sub-coating, the second precursor also undergoes a self-limiting chemical reaction with the first precursor chemically adsorbed on the inner wall surface of the valve, and the anti-corrosion sub-coating is also formed on the inner wall surface of the valve.

[0137] During repeated film deposition processes, the anti-corrosion coatings on the inner wall surfaces of the pipeline, the reaction chamber, and the valve are formed synchronously in the same film deposition step. This means that an anti-corrosion sub-coating is simultaneously superimposed on each inner wall surface in each film deposition process. After the same number of film deposition processes, the anti-corrosion coatings formed on the inner wall surfaces of the pipeline, valve, and reaction chamber have the same thickness.

[0138] In one specific embodiment, the first precursor is trimethylaluminum, the second precursor is ozone, the deposition temperature is 200°C, and both the first and second inert gases are nitrogen. Trimethylaluminum, as the first precursor, is introduced into the internal flow channel of a transport pipeline system heated to 200°C. The reaction chamber temperature is 300°C. Trimethylaluminum is chemically adsorbed onto the inner wall surfaces of the pipeline and the reaction chamber. After a first purging treatment using nitrogen as the first inert gas, ozone, as the second precursor, is introduced. The ozone reacts with the chemically adsorbed trimethylaluminum on the inner wall surfaces of the pipeline and the reaction chamber, undergoing a self-limiting chemical reaction to form an alumina anti-corrosion sub-coating on the inner wall surfaces of the pipeline and the reaction chamber. A second purging treatment is then performed using nitrogen as the second inert gas. The above film deposition process is repeated until the thickness of the alumina anti-corrosion coating reaches a preset thickness, which is 10 nanometers.

[0139] Accordingly, embodiments of the present invention also provide a precursor delivery pipeline system for an atomic layer deposition (ALD) machine. Wherein, Figure 4 This is a schematic diagram of a corresponding embodiment of the precursor delivery pipeline system for the atomic layer deposition machine of the present invention.

[0140] The precursor delivery pipeline system of the atomic layer deposition equipment includes interconnected pipelines 12 and reaction chambers 14. The inner wall surfaces of the pipelines 12 and the reaction chambers 14 define internal flow channels, and the inner wall surfaces defining the internal flow channels are deposited with an anti-corrosion coating formed by the deposition method provided by the present invention.

[0141] It should be noted that the precursor delivery pipeline system of the atomic layer deposition (ALD) machine provided in this embodiment has an anti-corrosion coating deposited on the inner wall surface of the pipeline 12 defining the internal flow channel and the inner wall surface of the reaction chamber 14. Since the anti-corrosion coating is formed using the deposition method described in any of the preceding embodiments, it is constructed by layering anti-corrosion sub-coatings formed in each film deposition process, resulting in a dense, pinhole-free structure that completely isolates the subsequently delivered corrosive precursor from the substrate on the inner wall surface of the pipeline 12 and the inner wall surface of the reaction chamber 14. When the pipeline system is delivered to the installation site of the ALD machine, the pipeline 12 and the reaction chamber 14 are already connected and installed, and the entire inner wall surface defining the internal flow channel is completely covered by the anti-corrosion coating. After installation on the ALD machine, no further treatment of the anti-corrosion coating is required, and the corrosive precursor can be directly introduced to perform the ALD process.

[0142] It should also be noted that the precursor delivery piping system may include multiple precursor sources 11, piping 12, valves 13, and a reaction chamber 14. The reaction chamber 14 is a container for holding the film-forming material. Multiple precursor sources 11 are connected to the reaction chamber 14 via piping 12 for pulsed precursors into the reaction chamber 14. Different precursor sources 11 can pulse different precursors into the reaction chamber 14. Within the reaction chamber 14, the precursors pulsed by different precursor sources 11 can react and form a film on the surface of the film-forming material. The diameter of the piping 12 can be, for example, 1 / 4 inch, 3 / 8 inch, 1 / 2 inch, etc. The material of the piping 12 can be, for example, stainless steel. Valves 13 are provided on the piping 12.

[0143] In some embodiments, the precursor delivery pipeline system further includes a purge gas source. The purge gas source is connected to the reaction chamber 14 via the pipeline 12 and is used to provide purge gas to remove residual precursors and reaction byproducts from the pipeline 12 and the reaction chamber 14.

[0144] In some embodiments, the precursor delivery piping system further includes a buffer container 15. The buffer container 15 can be a buffer cylinder. Multiple precursor sources 11 are connected to the buffer container 15 via piping 12. The buffer container 15 is connected to the reaction chamber 14 via piping 12. The precursor sources 11 can deliver precursors to the buffer container 15. The buffer container 15 buffers the precursors delivered by the precursor sources 11 and can pulse the precursors to the reaction chamber 14. Buffering can smooth pressure fluctuations and improve the stability of precursor pulses.

[0145] Accordingly, embodiments of the present invention also provide an atomic layer deposition apparatus, including a precursor delivery pipeline system, the precursor delivery pipeline system including interconnected pipelines and a reaction chamber, the inner wall surfaces of the pipelines and the reaction chamber defining internal flow channels, and the inner wall surfaces defining the internal flow channels being deposited with an anti-corrosion coating formed by the deposition method provided by the present invention.

[0146] The atomic layer deposition (ALD) equipment provided in this embodiment has a precursor delivery pipeline system comprising interconnected pipes and a reaction chamber. The inner wall surfaces of the pipes and reaction chamber define internal flow channels, and an anti-corrosion coating is deposited on the inner wall surfaces defining these flow channels. This anti-corrosion coating is formed on all inner wall surfaces defining the internal flow channels before the ALD equipment is first introduced with a corrosive process precursor. This ensures that the internal flow channels of the precursor delivery pipeline system are fully protected by the anti-corrosion coating during the first ALD process. After preventative maintenance, the precursor delivery pipeline system can be re-deposited in its current installed state, allowing the anti-corrosion coating to re-form on the damaged inner wall surface areas. This ensures that the ALD equipment continues to provide corrosion protection for the internal flow channels of the precursor delivery pipeline system throughout its service life.

[0147] While the present invention has been disclosed above, it is not limited thereto. Any person skilled in the art can make various modifications and alterations without departing from the spirit and scope of the invention; therefore, the scope of protection of the present invention should be determined by the scope defined in the claims.

Claims

1. A method for depositing an anti-corrosion coating on the inner wall of a precursor transport pipeline system for an atomic layer deposition (ALD) machine, the transport pipeline system comprising interconnected pipes and a reaction chamber, the inner wall surfaces of the pipes and the reaction chamber defining internal flow channels, the pipes having valve mounting positions, the transport pipeline system further comprising a valve mounted at the valve mounting positions, the internal flow channels being further defined by the inner wall surface of the valve, and the reaction chamber having a temperature control unit, characterized in that... include: With the transport pipeline system already installed and before the first introduction of the corrosive precursor for the process, the pipeline is heated to the deposition temperature using a heating element located outside the pipeline. The inner wall surface of the internal flow channel is subjected to multiple film deposition processes to form an anti-corrosion coating until the thickness of the anti-corrosion coating reaches a preset thickness. The anti-corrosion coating is composed of anti-corrosion sub-coatings formed in each film deposition process. During the film deposition process, the temperature of the reaction chamber is set independently of the temperature of the pipeline by the temperature control unit. The steps of the film deposition process include: A first precursor is introduced into the heated transport pipeline system, causing the first precursor to chemically adsorb onto the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. The first precursor also adsorbs onto the inner wall surface of the valve. A first inert gas is introduced into the transport pipeline system to perform a first purging treatment to remove the unadsorbed first precursor and the byproducts generated by the chemical adsorption. After the first purging treatment, a second precursor is introduced into the transport pipeline system so that the second precursor undergoes a self-limiting chemical reaction with the first precursor chemically adsorbed on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber, forming the anti-corrosion sub-coating on the inner wall surface of the pipeline and the inner wall surface of the reaction chamber. The second precursor also undergoes the self-limiting chemical reaction with the first precursor chemically adsorbed on the inner wall surface of the valve, and the anti-corrosion sub-coating is also formed on the inner wall surface of the valve. After the anti-corrosion sub-coating is formed, a second inert gas is introduced into the transport pipeline system for a second purging treatment to remove unreacted second precursor and byproducts generated by the self-limiting chemical reaction. After the anti-corrosion coating reaches a preset thickness, the transport pipeline system undergoes a third purging treatment. After the third purging process, the temperature of the transport pipeline system is adjusted from the deposition temperature to the temperature used for transporting the corrosive precursor for the process.

2. The anti-corrosion coating deposition method as described in claim 1, characterized in that, The heating element includes one or more of the following: resistance heating strip, metal heating block, and flexible heating clothing.

3. The anti-corrosion coating deposition method as described in claim 1, characterized in that, In the step of heating the pipeline to the deposition temperature, the deposition temperature is between 50°C and 250°C.

4. The anti-corrosion coating deposition method as described in claim 1, characterized in that, In the step of introducing a first precursor into the heated transport pipeline system, the first precursor is an aluminum-containing precursor or a silicon-containing precursor.

5. The anti-corrosion coating deposition method as described in claim 4, characterized in that, The aluminum-containing precursor includes one or more of trimethylaluminum, aluminum trichloride, triethylaluminum, tripropoxyaluminum, tridiethylaminoaluminum, and triethanolamine; The silicon-containing precursor includes one or more of the following: bis(tert-butylaminosilane), tri(tert-butoxysilanol), hexachlorosilane, tetramethylsilane, tetraethoxysilane, diisopropylaminosilane, and tridimethylaminosilane.

6. The anti-corrosion coating deposition method as described in claim 1, characterized in that, In the step of introducing a second precursor into the transport pipeline system, the second precursor is an oxidizing agent or a nitriding agent.

7. The anti-corrosion coating deposition method as described in claim 6, characterized in that, The oxidant includes one or more of water, hydrogen peroxide, ozone, nitrous oxide, oxygen free radicals, oxygen, and tert-butanol; The nitriding agent includes one or both of ammonia and nitrogen free radicals.

8. The anti-corrosion coating deposition method as described in claim 1, characterized in that, The first inert gas includes one or both of argon and nitrogen; The second inert gas includes one or both of argon and nitrogen.

9. The anti-corrosion coating deposition method as described in claim 1, characterized in that, The anti-corrosion coating is an oxide coating or a nitride coating.

10. The anti-corrosion coating deposition method as described in claim 9, characterized in that, The oxide coating includes one or more of Al2O3, SiO2, Y2O3, HfO2, ZrO2, AlSiO, HfAlO, and HfZrO; The nitride coating includes one or both of SiN and SiON.

11. The anti-corrosion coating deposition method as described in claim 1, characterized in that, The corrosive precursors used in the process include one or more of molybdenum pentachloride, molybdenum tetrachloride, molybdenum hexachloride, molybdenum bromide, molybdenum iodide, and molybdenum fluoride.

12. A precursor delivery piping system for an atomic layer deposition (ALD) machine, comprising interconnected pipes and a reaction chamber, wherein the inner wall surfaces of the pipes and the reaction chamber define internal flow channels, characterized in that... The inner wall surface defining the internal flow channel is deposited with an anti-corrosion coating formed by the deposition method of any one of claims 1 to 11.

13. An atomic layer deposition apparatus, characterized in that, The invention includes a precursor delivery pipeline system comprising interconnected pipelines and a reaction chamber, wherein the inner wall surfaces of the pipelines and the reaction chamber define internal flow channels, and the inner wall surfaces defining the internal flow channels are deposited with an anti-corrosion coating formed by the deposition method of any one of claims 1 to 11.

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