High temperature degassing apparatus, method and system for a solid precursor delivery system

Abstract

The application discloses a high-temperature degassing device, a degassing method and a system of a solid-state precursor conveying system, and relates to the technical field of semiconductor equipment manufacturing. The device comprises: a degassing main cavity having a precursor gas phase input port, an output port and a degassing vacuum port; a gas selective permeation tube assembly accommodated in the degassing main cavity, a degassing vacuum cavity being formed between the outer wall of the tube and the inner wall of the cavity; and a multi-section independent temperature control assembly comprising multiple groups of heating elements and temperature detection units distributed in different sections along the axial direction of the degassing main cavity, each group being independently controlled in a closed loop to eliminate cold spot temperature differences along the inner wall of the tube. The device eliminates cold point condensation through multi-section independent temperature control, eliminates thermal cycle leakage through a thermal expansion gradient matching sealing structure, and enhances degassing efficiency through a gas flow disturbance assembly, thereby solving the technical problem that the prior art cannot reliably degas solid-state precursors in a high-temperature gas phase environment.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor equipment manufacturing technology, and specifically relates to a high-temperature degassing device, degassing method and system for a solid precursor delivery system. Background Technology

[0002] In the fabrication of advanced semiconductor logic chips, dynamic random access memory (DRAM), and 3D NAND flash memory devices, thin films made of molybdenum (Mo), molybdenum nitride (MoN), and molybdenum oxide (MoOxOy) are gradually replacing traditional tungsten (W), titanium nitride (TiN), and cobalt (Co) films due to their extremely low resistivity, excellent thermal stability, and strong resistance to electromigration. When growing these high-performance molybdenum-based thin films, high-purity solid precursors (such as molybdenum dioxide (MoO2Cl2) and molybdenum pentachloride (MoCl5)) are typically used as the reaction source. The solid precursors are converted into a gaseous state and transported to the reaction chamber via sublimation.

[0003] Existing liquid precursor delivery systems operate at room temperature and are typically equipped with room temperature degassing membrane devices to eliminate disturbances to the process gas pressure and film quality in subsequent reaction chambers caused by inert carrier gases (such as helium, He) dissolved in the liquid precursor. These room temperature degassing devices generally operate within the range of 15°C to 40°C, using conventional polymer membrane materials such as polytetrafluoroethylene (PTFE) or ordinary polyimide, and their outer shells are mostly made of stainless steel or aluminum alloy.

[0004] However, in sublimation vapor transport systems for solid precursors, traditional room-temperature degassing devices face the following technical bottlenecks: (1) Cold point condensation and pipeline blockage: The solid precursor is completely solid at room temperature, and its sublimation and transport process must be carried out in a high-precision temperature control environment with full gas phase and high temperature (usually 80℃ to 200℃). If a room temperature degassing device is introduced into the pipeline, a sudden drop in temperature (cold point) is very likely to occur in a local area inside the degassing chamber, at the pipeline connection or on the membrane surface, causing the sublimated gaseous precursor to instantly recrystallize, resulting in blockage of the degassing membrane pores, a sharp increase in system airflow resistance, or even scrapping of the entire pipeline.

[0005] (2) Leakage caused by thermal stress and thermal mismatch: As the entire system is under high vacuum and periodic and severe temperature fluctuations, the internal diaphragm, support frame and external metal shell of the degassing membrane assembly have different coefficients of thermal expansion at high temperatures (above 150°C). Thermal mismatch can easily lead to creep damage of the sealing surface, causing unacceptable precursor leakage or infiltration of external air. Oxygen and moisture will directly cause precursor deterioration and contaminate the chamber.

[0006] (3) High-temperature corrosion and membrane material degradation: MoO2Cl2 and MoCl5 have extremely strong corrosiveness and permeability at high temperatures, especially when trace amounts of moisture are present, they will release highly acidic hydrogen chloride (HCl) gas. The polymer materials of traditional degassing membranes are prone to chain shearing, swelling, and a sharp decrease in mechanical strength under high temperature and highly acidic gas phase environments, thereby shortening their service life and even causing process accidents due to membrane rupture.

[0007] In the prior art, patent document CN223542500U discloses a degassing device and its thin film deposition equipment, which uses Teflon tubing as the degassing tube and adds a heating unit and a vibration unit to the outside of the degassing tube to heat and vibrate the liquid reaction source to precipitate bubbles. However, this device is designed for the degassing of liquid-phase reaction sources, and its operating temperature is far below the high-temperature range required for the sublimation and transport of solid precursors. Furthermore, it does not consider the problem of preventing condensation at cold points in the gas phase environment or the sealing leakage problem caused by high-temperature thermal expansion mismatch.

[0008] Therefore, there is an urgent need to design a degassing device that can adapt to the high-temperature operating conditions of solid precursor gas phase delivery systems and avoid cold spot condensation, thermal mismatch leakage and high-temperature corrosion. Summary of the Invention

[0009] In view of the problems in the related technologies, the present invention proposes a high-temperature degassing device, degassing method and system for a solid precursor delivery system, so as to overcome the above-mentioned technical problems existing in the existing related technologies.

[0010] To solve the above-mentioned technical problems, the present invention is achieved through the following technical solution: A high-temperature degassing device for a solid precursor conveying system, suitable for conveying solid precursors in environments with temperatures ranging from 80°C to 220°C, comprising: The degassing main chamber has a precursor gas phase input port and a precursor gas phase output port, and the chamber wall of the degassing main chamber is provided with a degassing vacuum port that is connected to the vacuum exhaust system. A gas selective permeation tube assembly is housed inside the degassing main cavity, including at least one gas selective permeation tube. The two ends of the gas selective permeation tube are in fluid communication with the precursor gas phase input port and the precursor gas phase output port, respectively. A degassing vacuum cavity is formed between the outer wall of the gas selective permeation tube and the inner wall of the degassing main cavity. The multi-segment independent temperature control assembly includes multiple sets of heating elements and temperature detection units distributed along the axial direction of the main degassing chamber in different segments. Each set of heating elements responds to the corresponding temperature detection unit to perform independent closed-loop temperature control, so as to eliminate the cold point temperature difference along the inner wall of the gas selective permeation tube.

[0011] As a preferred technical solution, the gas selective permeation tube is made of a heat-resistant and corrosion-resistant gas selective permeation material.

[0012] As a preferred technical solution, the sealing structure at both ends of the gas selective permeation tube assembly includes a thermal expansion compensation component. The thermal expansion compensation component includes, from the inside to the outside, a sealing ring in contact with the outer wall of the gas selective permeation tube, a gradient transition ring located in the middle layer, and a rigid ferrule pressure ring located in the outer layer. The thermal expansion coefficient of the gradient transition ring is between the thermal expansion coefficient of the gas selective permeation tube material and the thermal expansion coefficient of the degassing main cavity material.

[0013] As a preferred technical solution, the gradient transition ring is made of a metal-ceramic gradient composite material, and its thermal expansion coefficient is adjusted to the intermediate value between the thermal expansion coefficient of the gas selective permeation tube material and the thermal expansion coefficient of the degassing main cavity material through the component gradient ratio.

[0014] As a preferred technical solution, the multi-segment independent temperature control assembly includes at least three independent temperature control units: an inlet preheating compensation section, a middle degassing and constant temperature section, and an outlet insulation and protection section, wherein: The inlet preheating compensation section is located at the precursor gas phase input port and is used to lock the input gaseous precursor at a set target temperature T. set ; The central degassing and temperature control section is located on the outer wall of the central part of the main degassing cavity, and is used to maintain the temperature in the central part of the cavity at the target temperature T. set The sum of the positive overheat compensation value; The outlet insulation and protection section is located at the precursor gas phase output port and is used to maintain the output gas flow temperature at the target temperature T. set .

[0015] As a preferred technical solution, each of the independent temperature control units adopts PID closed-loop control.

[0016] As a preferred technical solution, the target temperature T set The temperature range is 80℃~220℃.

[0017] As a preferred technical solution, the positive overheat compensation value is 2℃~5℃.

[0018] As a preferred technical solution, the gas selective permeation material is a perfluorosulfonic acid polymer membrane material or an inorganic porous ceramic membrane material.

[0019] As a preferred technical solution, the inorganic porous ceramic membrane material is a ZrO2 ceramic membrane or a γ-Al2O3 ceramic membrane, and its inner surface is composited with a silanized hydrophobic layer.

[0020] As a preferred technical solution, the degassing main chamber is made of a corrosion-resistant metal material, which is either Hastelloy or 316L stainless steel with a passivated corrosion-resistant fluoropolymer coating on the outer surface.

[0021] As a preferred technical solution, an airflow disturbance component is provided inside the gas selective permeation tube assembly or inside the precursor gas phase input port pipeline. The airflow disturbance component is used to disrupt the laminar boundary layer of the airflow inside the gas selective permeation tube, so as to enhance the radial diffusion of gas molecules to the wall of the gas selective permeation tube.

[0022] As a preferred technical solution, the airflow disturbance component is a spiral micro-disturbance wing or a cross-mesh micro-disturbance wing.

[0023] As a preferred technical solution, the degassing vacuum chamber maintains a vacuum level of 10 during operation. -2 ~10 2 Pa.

[0024] As a preferred technical solution, the multi-segment independent temperature control component also includes an outermost heat insulation layer, which is made of microporous ceramic aerogel material.

[0025] As a preferred technical solution, the heating element includes an electric heating jacket or an electric heating wire, and the temperature detection unit includes a platinum resistance temperature sensor.

[0026] This invention also proposes a high-temperature degassing method for a solid precursor gas phase delivery system, applied to the aforementioned high-temperature degassing device, comprising the following steps: A gaseous-solid precursor containing non-condensable impurities is introduced into the gas selective permeation tube of the gas selective permeation tube assembly through the precursor gas phase input port. The multi-segment independent temperature control component is used to independently control the temperature of the inlet section, middle section and outlet section of the degassing main cavity, so as to eliminate the cold point temperature difference along the axial direction of the inner wall surface of the gas selective permeation tube; The vacuum level of the degassing vacuum chamber is maintained, allowing the non-condensable impurity gas to penetrate the wall of the gas selective permeation tube and enter the degassing vacuum chamber under the drive of the partial pressure difference, and be removed by the vacuum exhaust system. Meanwhile, the high molecular weight gaseous solid precursor molecules are retained in the gas selective permeation tube and discharged from the precursor gas phase output port.

[0027] As a preferred technical solution, the independent temperature control includes: The temperature of the inlet section is controlled within ±0.5℃ of the set target temperature; The temperature in the central section is controlled as a sum of the target temperature and the positive overheat compensation value of 2℃ to 5℃. The temperature of the outlet section is controlled at the target temperature.

[0028] As a preferred technical solution, the method further includes: using an airflow disturbance component disposed inside the gas selective permeation tube or in the inlet pipe to disrupt the laminar boundary layer of the airflow.

[0029] The present invention also proposes a solid precursor gas phase delivery system, including a solid precursor sublimation source and the aforementioned high-temperature degassing device, wherein the precursor gas phase input port of the high-temperature degassing device is connected to the gas phase output port of the solid precursor sublimation source.

[0030] As a preferred technical solution, the solid precursor contained in the solid precursor sublimation source is MoO2Cl2 or MoCl5.

[0031] Compared with the prior art, the present invention has the following beneficial effects: (1) Through the multi-segment independent high-precision closed-loop temperature control architecture and the central overheat compensation design, the zero cold point of the entire flow path is realized, ensuring that the surface temperature of all contact gases inside the degassing device is completely consistent and there are no dead corners of condensation. This effectively prevents the solid precursor from condensing and crystallizing in the degassing component, and solves the fundamental problem that the room temperature degassing device in the existing technology cannot be used in high temperature gas phase systems.

[0032] (2) The gas selective permeation tube is made of heat-resistant and corrosion-resistant permeation material, combined with a corrosion-resistant special metal shell, which can withstand the impact of high temperature and strong corrosive gas phase environment and run continuously for more than 1,500 hours without corrosion degradation.

[0033] (3) By introducing a gradient transition ring with a thermal expansion coefficient between the pipe material and the shell material, a thermal expansion compensation sealing structure is constructed, which makes the system have a low leakage rate at the seal during the drastic temperature alternation cycle from room temperature to equipment operating temperature, and is safe and stable. Attached Figure Description

[0034] 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.

[0035] Figure 1 This is a schematic diagram of the high-temperature degassing device of a solid precursor delivery system according to the present invention; Figure 2 This is a schematic diagram of the thermal expansion compensation component of a high-temperature degassing device for a solid precursor delivery system according to the present invention.

[0036] Among them: 1-Degassing main chamber, 2-Permeation tube assembly, 3-Independent temperature control assembly; 11 - Input port, 12 - Output port, 13 - Degassing vacuum port; 21-Permeation tube, 22-Degassing vacuum chamber; 31-Heating element; 32-Temperature detection unit; 201 - Sealing ring, 202 - Transition ring, 203 - Compression ring; 301 - Inlet preheating compensation section, 302 - Middle degassing and constant temperature section, 303 - Outlet insulation and protection section. Detailed Implementation

[0037] 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.

[0038] 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.

[0039] refer to Figure 1-2 As shown, a high-temperature degassing device for a solid precursor conveying system is suitable for conveying solid precursors in an environment with a temperature range of 80℃ to 220℃. It includes: a degassing main chamber 1, a gas selective permeation tube assembly 2, and a multi-segment independent temperature control assembly 3.

[0040] The degassing main chamber 1 of the present invention has a precursor gas phase input port 11 and a precursor gas phase output port 12, and the cavity wall of the degassing main chamber 1 is provided with a degassing vacuum port 13 that is connected to the vacuum exhaust system; wherein, the degassing main chamber 1 is made of a corrosion-resistant metal material, the metal material being Hastelloy or 316L stainless steel with a passivated corrosion-resistant fluoropolymer coating on the outer surface.

[0041] The gas selective permeation tube assembly 2 of the present invention is housed inside the degassing main cavity 1, and includes at least one gas selective permeation tube 21. The two ends of the gas selective permeation tube 21 are in fluid communication with the precursor gas phase input port 11 and the precursor gas phase output port 12, respectively. A degassing vacuum cavity 22 is formed between the outer wall of the gas selective permeation tube 21 and the inner wall of the degassing main cavity 1. The gas selective permeation tube 21 is made of a heat-resistant and corrosion-resistant gas selective permeation material. Further, the gas selective permeation material is a perfluorosulfonic acid polymer membrane material or an inorganic porous ceramic membrane material. Preferably, the inorganic porous ceramic membrane material is a ZrO2 ceramic membrane or a γ-Al2O3 ceramic membrane, and its inner surface is coated with a silanized hydrophobic layer. The degassing vacuum cavity 22 maintains a vacuum level of 10⁻⁶ during operation. -2 ~10 2 Pa.

[0042] The multi-section independent temperature control assembly 3 of the present invention includes multiple sets of heating elements 31 and temperature detection units 32 distributed axially along different sections of the main degassing chamber 1. Each set of heating elements 31 responds to the corresponding temperature detection unit 32 to perform independent closed-loop temperature control, thereby eliminating the cold point temperature difference along the inner wall of the gas selective permeation tube 21. Generally, the multi-section independent temperature control assembly 3 includes at least three sets of independent temperature control units: an inlet preheating compensation section 301, a middle degassing constant temperature section 302, and an outlet insulation and protection section 303, wherein: The inlet preheating compensation section 301 is located at the precursor gas phase input port 11 and is used to lock the input gaseous precursor at the set target temperature T. set ; The central degassing and temperature control section 302 is located on the outer wall of the central part of the main degassing chamber 1, and is used to maintain the temperature in the central part of the chamber at the target temperature T. set The sum of the positive overheat compensation value; The outlet insulation protection section 303 is installed at the precursor gas phase output port 12 to maintain the output gas flow temperature at the target temperature T. set .

[0043] Each independent temperature control unit in this invention employs PID closed-loop control, with a target temperature T. set The temperature range is 80℃~220℃, and the positive overheat compensation value is 2℃~5℃.

[0044] The sealing structure at both ends of the gas selective permeation tube assembly 2 of the present invention includes a thermal expansion compensation component. The thermal expansion compensation component includes, from the inside to the outside, a sealing ring 201 in contact with the outer wall of the gas selective permeation tube 21, a gradient transition ring 202 located in the middle layer, and a rigid ferrule pressure ring 203 located in the outer layer. The thermal expansion coefficient of the gradient transition ring 202 is between the thermal expansion coefficient of the gas selective permeation tube 21 and the thermal expansion coefficient of the degassing main cavity 1.

[0045] The gradient transition ring 202 of the present invention is made of metal-ceramic gradient composite material, and its thermal expansion coefficient is adjusted by the component gradient ratio to the intermediate value between the thermal expansion coefficient of the gas selective permeation tube 21 material and the thermal expansion coefficient of the degassing main cavity 1 material.

[0046] An airflow disturbance component is provided inside the gas selective permeation tube assembly 2 or in the precursor gas phase input port 11 of the present invention. The airflow disturbance component is used to disrupt the laminar boundary layer of the airflow inside the gas selective permeation tube 21, so as to enhance the radial diffusion of gas molecules towards the wall of the gas selective permeation tube 21. The airflow disturbance component is a spiral micro-disturbance fin or a cross-mesh micro-disturbance fin.

[0047] The multi-segment independent temperature control component 3 of the present invention also includes an outermost heat insulation layer (not shown in the figure), which is made of microporous ceramic aerogel material. The heating element 31 includes an electric heating jacket or an electric heating wire, and the temperature detection unit 32 includes a platinum resistance temperature sensor.

[0048] This invention also proposes a high-temperature degassing method for a solid precursor gas phase delivery system, applied to the aforementioned high-temperature degassing device, comprising the following steps: The gaseous solid precursor containing non-condensable impurities flows through the precursor gas phase input port 11 into the gas selective permeation tube 21 of the gas selective permeation tube assembly 2. The inlet section, middle section and outlet section of the degassing main chamber 1 are independently controlled by the multi-section independent temperature control component 3 to eliminate the cold point temperature difference along the axial direction of the inner wall surface of the gas selective permeation tube 21. Maintaining the vacuum level of the degassing vacuum chamber 22 allows non-condensable impurity gases to penetrate the wall of the gas selective permeation tube 21 under the drive of partial pressure difference and enter the degassing vacuum chamber 22, where they are removed by the vacuum exhaust system. Meanwhile, high molecular weight gaseous-solid precursor molecules are retained in the gas selective permeation tube 21 and discharged from the precursor gas phase output port 12.

[0049] Independent temperature control includes: The temperature of the inlet section is controlled within ±0.5℃ of the set target temperature; The temperature in the central section is controlled at the sum of the target temperature and the positive overheat compensation value of 2℃~5℃. Control the temperature of the outlet section at the target temperature.

[0050] The degassing method of the present invention further includes the step of disrupting the laminar boundary layer of the gas flow by using an airflow disturbance component disposed inside the gas selective permeation tube 21 or in the inlet pipe.

[0051] This invention also proposes a solid precursor gas phase delivery system, including a solid precursor sublimation source and the aforementioned high-temperature degassing device, wherein the precursor gas phase input port 11 of the high-temperature degassing device is connected to the gas phase output port of the solid precursor sublimation source. The solid precursor contained in the solid precursor sublimation source is MoO2Cl2 or MoCl5.

[0052] Example 1: Degassing device for a molybdenum dioxide (MoO2Cl2) sublimation system This embodiment addresses the sublimation delivery system of MoO2Cl2 solid precursor used in the metal barrier layer deposition process of advanced logic chips.

[0053] like Figure 1 As shown, this embodiment provides a high-temperature degassing device, including a degassing main chamber 1 shell made of Hastelloy C-276 and a bundle of ZrO2 inorganic ceramic gas selective permeation tubes 21 installed inside the degassing main chamber 1 shell. The degassing main chamber 1 shell is generally hollow cylindrical, with a precursor gas phase input port 11 and a precursor gas phase output port 12 respectively provided on both sides, and a degassing vacuum port 13 connected to a vacuum exhaust system is provided at the bottom of the shell.

[0054] (a) Sealed connection structure like Figure 2 As shown, considering the high permeability of MoO2Cl2 at high temperatures and the operating temperature of the pipeline at 145℃, the two ends of the ZrO2 inorganic ceramic gas selective permeation pipe assembly 2 are equipped with thermal expansion gradient matching sealing components. This sealing assembly, from the inside out, consists of: a modified perfluoropolyimide V-shaped sealing ring 201 on the outside of the tube bundle, an alumina-based metal-ceramic gradient transition ring 202, and a 316L stainless steel ferrule pressure ring 203.

[0055] In this embodiment, the coefficient of linear expansion of the ZrO2 inorganic ceramic tube is approximately 10 × 10⁻⁶. -6 / K; The linear expansion coefficient of 316L stainless steel is approximately 16×10 / K. The gradient transition ring 202, through precise sintering component gradient ratio design, sets its linear expansion coefficient at 12.8×10 / K, so that the thermal expansion coefficients of the three components form a smooth gradient transition from the inside to the outside.

[0056] When the degassing unit is heated from room temperature (approximately 20°C) to its normal operating temperature of 150°C, the radial thermal expansion difference between the outer wall of the pipe and the metal shell is approximately 0.09 mm / m. Without a gradient transition, this expansion difference would be entirely converted into the compressive shear deformation of the sealing ring 201. However, with the introduction of the gradient transition ring 202, the expansion difference is distributed across two interfaces: the pipe-transition ring 202 interface and the transition ring 202-shell interface. The expansion difference shared by each interface is reduced to approximately 0.043 mm / m and 0.047 mm / m, respectively, thus reducing the local shear stress borne by the sealing ring 201 by 72%. Through this gradient design, even after more than 500 start-up-stop thermal cycles, the micro-leakage rate at the system connections remains consistently below 5 × 10⁻⁶. -10 Pa·m 3 / s.

[0057] (ii) Temperature control and anti-cold point system Since the suitable operating temperature corresponding to the sublimation saturated vapor pressure of MoO2Cl2 is in the range of 130°C to 150°C, this embodiment sets the degassing target temperature T. set Set to 145℃.

[0058] The multi-zone independent temperature control component 3 adopts a three-stage closed-loop PID temperature control architecture: Inlet preheating compensation section 301: Located at the precursor gas phase input port 11. This section uses a high-frequency silicon controlled rectifier (SCR) to regulate power, combined with a direct-contact PT1000 platinum resistance temperature sensor for feedback. Through a fast-response PID algorithm, it precisely locks the precursor gas flow from the upstream pipeline, which has an uneven temperature distribution, at 145.0±0.2℃ at the inlet.

[0059] The central degassing and constant-temperature section 302 is located on the outer wall of the central part of the main degassing chamber 1. A high-performance ceramic fiber electric heating jacket is wound around the outer wall of the chamber, and a 5mm thick uniform-temperature copper sleeve is used in conjunction with it. To absolutely prevent phase change condensation of the precursor gas due to localized expansion and cooling within the degassing chamber, the outer surface temperature of the central degassing chamber is set at 148.5℃ (i.e., T). set (Precise and safe superheat of +3.5℃).

[0060] Outlet insulation protection section 303: Located at the precursor gas phase output port 12, it uses an independent PID temperature control unit to precisely maintain the outlet pipeline temperature at 145.0℃, ensuring that there are no cold spots in the outlet gas flow path.

[0061] In the steady-state operation of this embodiment, the maximum axial temperature difference ΔT on the inner wall of the gas selective permeation tube 21 bundle 2 is verified by using this three-stage gradient temperature control strategy and fluid finite element analysis and measured data from airborne temperature sensors. max ≤0.4℃, with no precursor condensation or crystallization cold spots throughout the entire flow path.

[0062] (III) Performance in removing gaseous impurities In this embodiment, the degassing vacuum port 13 is connected to a two-stage vacuum pump group (molecular pump + dry pump) to maintain the vacuum level of the degassing vacuum chamber 22 at 1 Pa.

[0063] Experimental conditions: Saturated MoO₂Cl₂ gas at a flow rate of 500 sccm, doped with 1% molar ratio of He and 0.5% molar ratio of N₂ as simulated impurity gases; T set =145℃.

[0064] The degassing mechanism is as follows: Non-condensable inert light impurity gases (such as He, with a molecular weight of 4 g / mol; N2, with a molecular weight of 28 g / mol) have extremely high molecular free path at high temperature (145℃) and large partial pressure difference across the membrane, which can penetrate the tube wall and enter the degassing vacuum chamber 22 and be pumped away; while large molecular weight gaseous solid precursor molecules (MoO2Cl2, with a molecular weight of 198.85 g / mol) are completely confined to transport within the tube due to their large molecular dynamic diameter and the selective retention effect of the membrane on polar macromolecules.

[0065] Experimental results: After passing through this high-temperature degassing device, the removal rate of He impurities in the precursor gas flow reached 99.85%, the removal rate of N2 reached 98.12%, and the transmembrane loss of MoO2Cl2 was less than 0.02%. After continuous operation for 1500 hours, disassembly and inspection showed that there was no corrosion reaction layer or solid precursor crystal accumulation on the inner surface of the ZrO2 ceramic tube.

[0066] (iv) Summary of beneficial effects This embodiment utilizes a Hastelloy C-276 shell to provide basic corrosion resistance, ZrO2 inorganic ceramic tube bundles to achieve selective gas permeation and HCl corrosion resistance at high temperatures, thermal expansion gradient matching sealing components to eliminate leakage risks during thermal cycling, a multi-segment PID temperature control architecture to completely eliminate the risk of cold spot condensation, and high vacuum maintenance in the degassing vacuum chamber 22 to achieve efficient removal of impurity gases. All subsystems work together to meet the comprehensive performance requirements of the solid precursor sublimation delivery system for the degassing device under high temperature, high vacuum, and highly corrosive environments.

[0067] Example 2: High-temperature degassing device for molybdenum pentachloride (MoCl5) sublimation system This embodiment focuses on the MoCl5 solid-state precursor sublimation delivery system used in the fabrication process of high aspect ratio word lines for 3D NAND flash memory. MoCl5 exhibits stronger chemical corrosiveness to moisture and metal surfaces at high temperatures than MoO2Cl2, and the process requires operating temperatures to be maintained between 170°C and 190°C.

[0068] (a) Selection of tube bundle materials This embodiment uses 21 bundles of special high-temperature corrosion-resistant modified perfluorosulfonic acid (PFSA) gas selective permeation tubes. By modifying the aromatic rings, the glass transition temperature of PFSA is increased from the traditional approximately 110°C to 245°C, ensuring that the mechanical properties and gas selective permeation performance of the membrane do not decrease at an operating temperature of 180°C.

[0069] (ii) Temperature parameter setting Set T set =180℃. The central degassing and constant temperature section 302 is set at 183.0℃ (+3℃ safe superheat). The inlet preheating compensation section 301 and the outlet insulation protection section 303 are both controlled at 180.0±0.3℃. Each section adopts PID closed-loop control, and the temperature fluctuation is controlled within ±0.3℃ of the set value.

[0070] (iii) Enhancement of airflow disturbance A spiral gas boundary layer disturbance made of nickel-based Hastelloy is installed inside the input pipe. Under high-temperature conditions, the gas viscosity increases and the Reynolds number decreases, causing the gas flow inside the pipe to tend to be laminar. The radial diffusion of gas molecules towards the pipe wall is mainly driven by Brownian motion, which limits the mass transfer efficiency.

[0071] By introducing a helical disturbance, the radial Reynolds number of the airflow within the tube bundle is locally increased from Re=120 (typical laminar flow) to a transitional flow state, significantly enhancing radial mixing and the collision frequency of gas molecules penetrating the tube wall membrane. Experimental results show that, with the total length of the degassing chamber shortened by 30% compared to the disturbance-free scheme, the He removal rate increased from 82.3% to 99.2%, and the N2 removal rate increased from 75.1% to 97.8%, while the pressure loss of the precursor at the outlet only increased slightly by 12 Pa, which is well within the upstream control precision range of semiconductor process chambers (typically required to be less than 100 Pa).

[0072] (iv) Comparative Analysis .

[0073] Finally, it should be noted that, in addition to the ZrO2 ceramic membrane and modified PFSA membrane specifically used in the two embodiments above, the gas selective permeation tube of the present invention may also be selected from any one or more combinations of the following materials: (1) γ-Al2O3 porous ceramic ultrafiltration membrane with a pore size range of 2 to 50 nm and a silanized hydrophobic layer on the inner surface to enhance the retention effect on polar macromolecular precursors. (2) Yttrium oxide stabilized zirconia (YSZ) ceramic film; (3) High-temperature modified Nafion membrane (perfluorosulfonic acid / PTFE composite membrane); (4) Silicon carbide (SiC) porous ceramic membrane.

[0074] The selection of different membrane materials can be adapted according to the chemical properties (such as acidity and oxidizing properties) and operating temperature range of the specific solid precursor, and all of these fall within the protection scope of this invention.

[0075] 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.

[0076] 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. A high-temperature degassing device for a solid precursor conveying system, characterized in that, Suitable for conveying solid precursors in environments with a temperature range of 80°C to 220°C, including: The degassing main chamber has a precursor gas phase input port and a precursor gas phase output port, and the chamber wall of the degassing main chamber is provided with a degassing vacuum port that is connected to the vacuum exhaust system. A gas selective permeation tube assembly is housed inside the degassing main cavity, including at least one gas selective permeation tube. The two ends of the gas selective permeation tube are in fluid communication with the precursor gas phase input port and the precursor gas phase output port, respectively. A degassing vacuum cavity is formed between the outer wall of the gas selective permeation tube and the inner wall of the degassing main cavity. The multi-segment independent temperature control assembly includes multiple sets of heating elements and temperature detection units distributed along the axial direction of the main degassing chamber in different segments. Each set of heating elements responds to the corresponding temperature detection unit to perform independent closed-loop temperature control, so as to eliminate the cold point temperature difference along the inner wall of the gas selective permeation tube. The sealing structure at both ends of the gas selective permeation tube assembly includes a thermal expansion compensation component, which, from the inside out, includes: a sealing ring in contact with the outer wall of the gas selective permeation tube, a gradient transition ring in the middle layer, and a rigid ferrule pressure ring in the outer layer; wherein, the thermal expansion coefficient of the gradient transition ring is between the thermal expansion coefficient of the gas selective permeation tube material and the thermal expansion coefficient of the degassing main cavity material. The multi-segment independent temperature control assembly includes at least three independent temperature control units: an inlet preheating compensation section, a middle degassing and constant temperature section, and an outlet insulation and protection section. The inlet preheating compensation section is located at the precursor gas phase input port and is used to lock the input gaseous precursor at a set target temperature. The central degassing constant temperature section is located on the outer wall of the central part of the main degassing cavity, and is used to maintain the temperature in the central part of the cavity at the sum of the target temperature and the positive overheat compensation value; The outlet insulation protection section is located at the precursor gas phase output port and is used to maintain the output gas flow temperature at the target temperature.

2. The high-temperature degassing device according to claim 1, characterized in that, The gradient transition ring is made of a metal-ceramic gradient composite material, and its coefficient of thermal expansion is adjusted by the component gradient ratio to the middle value between the coefficient of thermal expansion of the gas selective permeation tube material and the coefficient of thermal expansion of the degassing main cavity material.

3. The high-temperature degassing device according to claim 1, characterized in that, The positive overheat compensation value is 2℃~5℃.

4. The high-temperature degassing device according to claim 1, characterized in that, An airflow disturbance component is provided inside the gas selective permeation tube assembly or in the precursor gas phase input port pipeline. The airflow disturbance component is used to disrupt the laminar boundary layer of the airflow inside the gas selective permeation tube to enhance the radial diffusion of gas molecules toward the wall of the gas selective permeation tube.

5. A high-temperature degassing method for a solid precursor gas phase transport system, applied to the high-temperature degassing apparatus as described in any one of claims 1 to 4, characterized in that, Includes the following steps: A gaseous-solid precursor containing non-condensable impurities is introduced into the gas selective permeation tube of the gas selective permeation tube assembly through the precursor gas phase input port. The multi-segment independent temperature control component is used to independently control the temperature of the inlet section, middle section and outlet section of the degassing main cavity, so as to eliminate the cold point temperature difference along the axial direction of the inner wall surface of the gas selective permeation tube; The vacuum level of the degassing vacuum chamber is maintained, allowing the non-condensable impurity gas to penetrate the wall of the gas selective permeation tube and enter the degassing vacuum chamber under the drive of the partial pressure difference, and be removed by the vacuum exhaust system. Meanwhile, the high molecular weight gaseous solid precursor molecules are retained in the gas selective permeation tube and discharged from the precursor gas phase output port.

6. The high-temperature degassing method according to claim 5, characterized in that, The independent temperature control includes: The temperature of the inlet section is controlled within ±0.5℃ of the set target temperature; The temperature in the central section is controlled as a sum of the target temperature and the positive overheat compensation value of 2℃ to 5℃. The temperature of the outlet section is controlled at the target temperature.

7. The high-temperature degassing method according to claim 5, characterized in that, It also includes the step of disrupting the laminar boundary layer of the gas flow by using an airflow disturbance component disposed inside the gas selective permeation tube or in the inlet pipe.

8. A solid precursor gas phase delivery system, characterized in that, The invention includes a solid precursor sublimation source and a high-temperature degassing device as described in any one of claims 1 to 4, wherein the precursor gas phase input port of the high-temperature degassing device is connected to the gas phase output port of the solid precursor sublimation source.

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