A remote plasma source cavity

Abstract

This application belongs to the technical field of plasma generation equipment and discloses a remote plasma source cavity, including an annular vacuum cavity, an air inlet, an air outlet, a magnetic core assembly, and an ignition coil. The annular vacuum cavity includes multiple straight channels connected end-to-end to form a closed-loop flow path. The magnetic core assembly is wound on at least one of the straight channels. The air inlet and the air outlet are respectively connected to two different straight channels. An adjustment electrode pair is provided at the connection point of any two adjacent straight channels. The adjustment electrode pair is used to generate a deflection electric field to drive charged particles in the gas flow to deflect and avoid contact between the charged particles and the circumferential sidewall of the annular vacuum cavity. This can extend the service life of the cavity, improve plasma purity, and improve plasma uniformity and stability.

Description

Technical Field

[0001] This application relates to the field of plasma generation equipment technology, and more specifically, to a remote plasma source cavity. Background Technology

[0002] Remote plasma source cavities are important devices for generating plasma, widely used in processes such as chamber cleaning, surface modification, thin film etching, and plasma-assisted deposition in semiconductor manufacturing and display panel production. Existing remote plasma source cavities typically use an alternating magnetic field to ionize fluorine-containing compounds to generate active fluorine ion gas. Their basic structure includes a toroidal vacuum chamber, an inlet, an outlet, a magnetic core assembly, and an ignition coil.

[0003] The inner wall of the annular vacuum chamber is typically coated with an oxide protective film, and the magnetic core assembly is wound around the outside of the annular vacuum chamber. The inlet and outlet are connected to the annular vacuum chamber, and the ignition coil is located at the inlet. During operation, the working gas, including an excitation gas (such as argon) and a process gas (such as nitrogen trifluoride), is introduced through the inlet. The ignition coil ignites the excitation gas, and the magnetic core assembly generates an alternating magnetic field to ionize the process gas, forming a plasma gas flow (such as an active fluoride ion gas flow), which is finally output from the outlet.

[0004] However, existing remote plasma source cavities have some technical drawbacks. First, most common annular vacuum cavities are rectangular, with large turning angles at the corners. When the gas flow turns, it is prone to friction and collision with the inner wall of the cavity due to inertia. This causes the active fluorine ion gas to directly contact and corrode the oxide protective film on the inner wall, severely affecting the service life of the cavity. Second, the reaction between the active fluorine ion gas and the oxide protective film produces particulate dust, reducing the purity of the plasma.

[0005] These issues not only reduce the operating efficiency and lifespan of remote plasma source cavities, but also affect the quality and consistency of plasma processing. Particularly in fields with high process requirements, such as semiconductor manufacturing, these defects can lead to decreased product yield and increased costs.

[0006] To address the aforementioned issues, existing technologies urgently need improvement. Summary of the Invention

[0007] The purpose of this application is to provide a remote plasma source cavity that can extend the cavity's service life, improve plasma purity, and enhance plasma uniformity and stability.

[0008] This application provides a remote plasma source cavity, including an annular vacuum cavity, an air inlet, an air outlet, a magnetic core assembly, and an ignition coil; the annular vacuum cavity includes multiple straight channels connected end-to-end to form a closed loop flow channel, at least one of the straight channels is wound with the magnetic core assembly, and the air inlet and the air outlet are respectively connected to two different straight channels; an adjustment electrode pair is provided at the connection point of any two adjacent straight channels, the adjustment electrode pair is used to generate a deflection electric field to drive charged particles in the airflow to turn, thereby avoiding contact between the charged particles and the circumferential sidewall of the annular vacuum cavity.

[0009] By adjusting the deflection electric field generated by the electrode pair, charged particles are driven to change direction, avoiding contact with the inner wall of the annular vacuum cavity. This solves the problem of friction and collision between plasma and the inner wall of the annular vacuum cavity in the prior art, and has the advantages of extending the service life of the cavity, improving plasma purity, and improving plasma uniformity and stability.

[0010] Preferably, the regulating electrode pair includes a positive electrode plate and a negative electrode plate disposed opposite to each other, the positive electrode plate being disposed on the outer circumferential sidewall of the annular vacuum cavity, and the negative electrode plate being disposed on the inner circumferential sidewall of the annular vacuum cavity.

[0011] This arrangement generates an electric field pointing inward from the outside of the cavity, effectively deflecting charged particles in the gas flow inward. This electrode arrangement also creates an effective deflecting electric field at the junction of adjacent linear cavities. When charged particles flow through this region, they are acted upon by the electric field force, changing their direction of motion and avoiding direct contact with the outer circumferential sidewalls of the annular vacuum cavity. This not only reduces particle collisions with the cavity walls and minimizes particle loss, but also extends the cavity's lifespan and improves plasma stability and homogeneity.

[0012] Preferably, any two adjacent linear cavities are connected by a connecting cavity, and the adjustment electrode pair is disposed at the connecting cavity.

[0013] The connecting channel not only connects adjacent linear channels but also provides a mounting location for the adjustment electrodes. Positioned at the connecting channel, the adjustment electrodes can generate a deflection electric field at key points where the airflow changes direction. This arrangement allows for more precise control of the charged particle's trajectory and effectively prevents charged particles from contacting the circumferential sidewalls of the annular vacuum cavity.

[0014] Optionally, the connecting cavity is a straight cavity.

[0015] Optionally, the connecting cavity is a curved cavity.

[0016] Preferably, a flow guide is provided on the inner surface of the outer peripheral sidewall at the connection between the connecting cavity and the upstream adjacent straight cavity, and a flow guide surface is provided on the inward side of the flow guide, which is used to guide the airflow to change direction.

[0017] Preferably, the flow guide is made partly or entirely of non-conductive ceramic.

[0018] Preferably, the flow guide is detachable.

[0019] Preferably, the air inlet and the air outlet are connected along a characteristic straight line to opposite sides of the annular vacuum cavity, the annular vacuum cavity is symmetrical about the characteristic straight line, and the magnetic core assembly is symmetrically distributed about the characteristic straight line.

[0020] Preferably, the annular vacuum cavity includes four linear channels, including two parallel first linear channels and two parallel second linear channels. The first linear channels are perpendicular to the second linear channels and the first linear channels are shorter than the second linear channels. The air inlet and the air outlet are respectively connected to the two first linear channels, and the magnetic core assembly is wound on the two second linear channels.

[0021] Beneficial effects: The remote plasma source cavity provided in this application includes multiple linear channels and adjustment electrode pairs disposed at the connection of the linear channels. The deflection electric field generated by the adjustment electrode pairs drives the charged particles to turn, avoiding contact with the inner wall of the annular vacuum cavity. This solves the problem of friction and collision between plasma and the inner wall of the annular vacuum cavity in the prior art, and has the advantages of extending the service life of the cavity, improving plasma purity, and improving plasma uniformity and stability. Attached Figure Description

[0022] Figure 1 A perspective view of a remote plasma source cavity provided in an embodiment of this application.

[0023] Figure 2 This is a cross-sectional view of a remote plasma source cavity provided in an embodiment of this application.

[0024] Figure 3 This is a schematic diagram illustrating the working principle of the adjusting electrode pair.

[0025] Figure 4 This is a schematic diagram illustrating the working principle of the flow guide.

[0026] Labeling Explanation: 1. Annular vacuum chamber; 101. Straight channel; 1011. First straight channel; 1012. Second straight channel; 102. Connecting channel; 2. Air inlet; 3. Air outlet; 4. Magnetic core assembly; 5. Ignition coil; 6. Adjusting electrode pair; 601. Positive electrode plate; 602. Negative electrode plate; 7. Flow guide; 701. Flow guide surface. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0028] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0029] Remote plasma source cavities play a crucial role in semiconductor manufacturing and surface treatment processes. However, existing remote plasma source cavities face significant challenges during operation. Because annular vacuum cavities often employ a rectangular design with large bends at the corners, the gas flow is prone to friction and collision with the inner wall of the cavity during turns. In this situation, active fluorine ions can come into contact with and corrode the protective oxide film on the inner wall of the annular vacuum cavity. This not only significantly shortens the lifespan of the remote plasma source cavity but also reduces plasma purity due to the reaction of active fluorine ions with the protective oxide film to generate particulate dust.

[0030] Failure to effectively address this issue will lead to a series of serious technical consequences. First, continuous corrosion of the cavity's inner wall will significantly shorten equipment lifespan. Second, as contaminant concentration increases, plasma purity will continuously decline, directly impacting the quality and consistency of etching and cleaning processes. Furthermore, corrosion products may deposit on the wafer surface, increasing defect density and further affecting device performance and reliability. In the long run, if this problem remains unresolved, it will become a bottleneck restricting further miniaturization and precision improvements in semiconductor manufacturing processes, hindering technological advancements across the entire industry. Therefore, a new technological solution is urgently needed to overcome these challenges and improve the performance and lifespan of remote plasma source cavities.

[0031] To address this issue, this application proposes a novel remote plasma source cavity design.

[0032] Please refer to Figures 1-4A remote plasma source cavity in some embodiments of this application includes an annular vacuum cavity 1, an air inlet 2, an air outlet 3, a magnetic core assembly 4, and an ignition coil 5. The annular vacuum cavity 1 includes a plurality of straight channels 101 connected end to end to form a closed loop flow channel. At least one straight channel 101 is wound with a magnetic core assembly 4. The air inlet 2 and the air outlet 3 are respectively connected to two different straight channels 101. An adjustment electrode pair 6 is provided at the connection of any two adjacent straight channels 101. The adjustment electrode pair 6 is used to generate a deflection electric field to drive the charged particles in the airflow to turn so as to avoid the charged particles from contacting the circumferential sidewall of the annular vacuum cavity 1.

[0033] This remote plasma source cavity drives charged particles to turn around by adjusting the deflection electric field generated by the electrode pair 6, thus avoiding contact with the inner wall of the annular vacuum cavity 1. This solves the problem of friction and collision between plasma and the inner wall of the annular vacuum cavity 1 in the prior art, and has the advantages of extending the service life of the cavity, improving plasma purity, and improving plasma uniformity and stability.

[0034] It should be noted that the annular vacuum cavity 1 has two parallel normal sidewalls, as well as an inner circumferential sidewall and an outer circumferential sidewall located between the two normal sidewalls. The two normal sidewalls, the inner circumferential sidewall, and the outer circumferential sidewall together form a closed-loop flow channel; Figure 4 For example, in the figure, a is the outer peripheral sidewall and b is the inner peripheral sidewall, and the two normal sidewalls are parallel to the paper.

[0035] The number and length of the linear cavities 101 can be set according to actual needs. The number and connection positions of the magnetic core assemblies 4 can also be set according to actual needs. By adjusting the number and length of the linear cavities 101 and the configuration of the magnetic core assemblies 4, the requirements of plasma sources of different scales and powers can be easily adapted.

[0036] The annular vacuum cavity 1 can be made of aluminum alloy (but is not limited to this), and its inner wall surface is provided with an oxide protective layer (for example, an aluminum oxide protective layer obtained by anodizing the inner surface of the side wall of the annular vacuum cavity 1).

[0037] The air inlet 2 and air outlet 3 can be made of high-temperature resistant non-conductive materials such as alumina and pyrolytic boron nitride, but are not limited to these.

[0038] Among them, the magnetic core assembly 4 and the ignition coil 5 are existing technologies, and their structures will not be described in detail here.

[0039] Specifically, see Figure 2 The adjusting electrode pair 6 includes a positive electrode plate 601 and a negative electrode plate 602 arranged opposite to each other. The positive electrode plate 601 is disposed on the outer circumferential sidewall of the annular vacuum cavity 1, and the negative electrode plate 602 is disposed on the inner circumferential sidewall of the annular vacuum cavity 1.

[0040] The positive electrode 601 and negative electrode 602 of the adjusting electrode pair 6 are respectively disposed on the outer circumferential sidewall and inner circumferential sidewall of the annular vacuum cavity 1, forming a transverse electric field (e.g., Figure 3 (As shown). This arrangement generates an electric field pointing inward from the outside of the cavity, effectively deflecting charged particles in the gas flow inward. This electrode arrangement also creates an effective deflection electric field at the junction of adjacent straight channels 101. When charged particles flow through this region, they are acted upon by the electric field force, changing their direction of motion and avoiding direct contact with the outer circumferential sidewall of the annular vacuum cavity 1. This not only reduces particle collisions with the cavity wall and decreases particle loss, but also extends the cavity's lifespan and improves plasma stability and uniformity. Furthermore, since the positive electrode 601 is located on the outside and the negative electrode 602 on the inside, this arrangement also prevents positively charged ions from directly impacting the inner wall of the cavity, further reducing cavity wear and contamination. Simultaneously, this electrode arrangement facilitates installation and maintenance; the electrode positions can be adjusted or replaced as needed, improving the maintainability and flexibility of the equipment.

[0041] The regulating electrode pair 6 in this application can be implemented in various forms. For example, the positive electrode plate 601 and the negative electrode plate 602 can be flat, arc-shaped, or other suitable shapes. The electrode material can be a metal with good conductivity and corrosion resistance, such as stainless steel or titanium alloy. To further improve the corrosion resistance of the electrodes, a protective layer, such as alumina or silicon nitride ceramic materials, can be coated on the electrode surface.

[0042] The mounting methods for the positive electrode plate 601 and the negative electrode plate 602 can also be flexibly designed. For example, they can be fixed with bolts, snap-on, or embedded. This facilitates electrode replacement and maintenance, improving the reliability and service life of the equipment.

[0043] In practical applications, the electric field strength can be controlled by adjusting the voltage between the positive and negative plates. For example, an adjustable DC power supply can be used to regulate the voltage between the positive and negative plates. By changing the voltage, the electric field strength can be flexibly adjusted to adapt to different process requirements and gas flow conditions.

[0044] In some preferred embodiments, see Figure 2 , Figure 3 Any two adjacent straight cavities 101 are connected by a connecting cavity 102, and the adjustment electrode pair 6 is set at the connecting cavity 102.

[0045] By setting a connecting channel 102 between adjacent linear channels 101, a closed-loop structure of the annular vacuum cavity 1 is achieved. The connecting channel 102 not only connects adjacent linear channels 101 but also provides an installation position for the adjusting electrode pair 6. The adjusting electrode pair 6, located at the connecting channel 102, can generate a deflection electric field at a critical point of airflow turning. This arrangement allows for more precise control of the trajectory of charged particles and effectively prevents charged particles from contacting the circumferential sidewalls of the annular vacuum cavity 1. By placing the adjusting electrode pair 6 at the connecting channel 102, this technical solution cleverly utilizes the position of airflow turning to control the movement of charged particles. This design not only simplifies the structure but also improves the accuracy and efficiency of charged particle motion control. Simultaneously, since the adjusting electrode pair 6 is located at the connecting channel 102, it does not interfere with the plasma generation and transport process in the linear channels 101, ensuring plasma stability. Furthermore, this design also offers good flexibility and adjustability. By adjusting the shape of the connecting cavity 102 (such as a straight cavity or a curved cavity) and adjusting the parameters of the electrode pair 6, the trajectory of charged particles can be further optimized to adapt to different application requirements.

[0046] The specific arrangement of the adjusting electrode pair 6 in the connecting cavity 102 can also be varied. A common arrangement is to place a pair of electrodes (a pair of electrodes includes a positive electrode plate 601 and a negative electrode plate 602) in the middle of the connecting cavity 102. Figure 2 (As shown). Another arrangement is to set a pair of electrodes at the entrance and exit of the connecting cavity 102 to form two independent deflection electric fields. A third arrangement is to set continuous electrode strips (i.e., the positive electrode plate 601 and the negative electrode plate 602 are both strip-shaped electrodes extending along the circumferential sidewall of the connecting cavity 102) on the inner and outer circumferential sidewalls to form a continuous deflection electric field.

[0047] When using the technical solution of this application to solve the connection and charged particle control problems between adjacent straight cavities 101, a smooth connection between adjacent straight cavities 101 is first achieved through the connecting cavity 102, avoiding abrupt changes at corners in traditional designs. This smooth transition significantly reduces turbulence and eddies in the airflow during turning, lowering the risk of charged particles colliding with the cavity wall. Secondly, the deflection electric field generated by the regulating electrode pair 6 at the connecting cavity 102 can precisely control the trajectory of charged particles. When charged particles enter the connecting cavity 102 with the airflow, the deflection electric field applies a force adapted to the airflow direction, guiding the charged particles along an ideal path and effectively preventing them from contacting the cavity wall.

[0048] In some possible implementations, see Figures 1-4 The connecting cavity 102 is a straight cavity.

[0049] The connecting cavity 102 adopts a straight-cavity design, which simplifies the cavity structure and reduces manufacturing difficulty. The shape of the straight cavity facilitates smooth airflow, reduces the generation of turbulence and eddies, and thus reduces energy loss. By designing the connecting cavity 102 as a straight cavity, a simple and efficient connection between adjacent straight cavities 101 can be achieved. The straight cavity structure is simple, easy to manufacture and maintain, and also facilitates the installation of the adjustment electrode pair 6. This design helps optimize the airflow path of the entire annular vacuum cavity 1, improving the uniformity and stability of the plasma. The straight-cavity design also reduces airflow resistance at bends, which helps maintain airflow velocity and pressure, thereby improving plasma generation efficiency. In addition, the straight-cavity structure also helps reduce collisions between charged particles and the cavity walls, further improving plasma quality.

[0050] The connection between the connecting cavity 102 and the adjacent straight cavity 101 can employ a smooth transition design to reduce airflow disturbance at bends. For example, a rounded corner transition can be used at the connection. This design can further reduce airflow resistance and improve plasma flow efficiency.

[0051] The length of the straight cavity can be set according to actual needs.

[0052] In some other possible implementations, the connecting cavity 102 is a curved cavity.

[0053] Using a curved cavity as the connecting cavity 102 allows for smoother airflow during turning, reducing turbulence and eddies. This design helps maintain airflow stability and reduces the probability of charged particles contacting the cavity walls. The curved cavity design, combined with the regulating electrode pair 6, allows for more effective control of the trajectory of charged particles in the airflow. The curved cavity provides a gradual turning path, while the deflection electric field generated by the regulating electrode pair 6 further guides the charged particles along the desired path. This combined design not only reduces particle collisions with the cavity walls but also improves plasma density and homogeneity. Furthermore, the curved cavity design may help extend the residence time of gas within the cavity, thereby increasing the chance of gas molecules being ionized and improving plasma generation efficiency. Simultaneously, the curved design may also contribute to a more uniform magnetic field distribution, further enhancing plasma stability and homogeneity.

[0054] The curved cavity can take on various shapes and designs. For example, the curved cavity can be arc-shaped or elliptical. An arc-shaped curved cavity can provide a smooth steering path, while an elliptical curved cavity can achieve a larger steering angle within a limited space.

[0055] Furthermore, the annular vacuum chamber 1 can be a one-piece molded structure, or it can be formed by connecting various independent channels (straight channels 101 and connecting channels 102) through a detachable connection method (for example, adjacent channels are fixedly and sealed by flange faces and sealing rings, but not limited to this). The one-piece molded structure can improve structural stability and sealing performance, while the independent detachable connection method makes it easier to install the components in the annular vacuum chamber 1 and to replace each component individually (to reduce maintenance costs).

[0056] In some preferred embodiments, see Figure 2 A flow guide 7 is provided on the inner surface of the outer peripheral sidewall at the connection between the connecting cavity 102 and the adjacent upstream straight cavity 101. A flow guide surface 701 is provided on the inward side of the flow guide 7, and the flow guide surface 701 is used to guide the airflow to change direction.

[0057] By providing a flow guide 7 at the connection between the connecting cavity 102 and the adjacent upstream straight cavity 101, the flow guide surface 701 on the inner side of the flow guide 7 is used to guide the airflow to change direction (e.g., Figure 4 (As shown). This design helps control the flow direction of the airflow and reduces the contact between charged particles in the airflow and the circumferential sidewall of the annular vacuum cavity 1. The placement of the guide 7 is carefully considered. It is located on the inner surface of the outer circumferential sidewall at the connection between the connecting channel 102 and the upstream adjacent straight channel 101, precisely where the airflow needs to be redirected. The guide surface 701 faces the interior of the cavity and can directly act on the flowing gas, effectively guiding the airflow to change direction. By guiding the airflow to change direction, this technical solution can reduce the probability of charged particles colliding with the wall of the annular vacuum cavity 1, thereby reducing particle loss and cavity contamination. This not only helps maintain the stability and density of the plasma but also extends the service life of the cavity and improves the overall efficiency and reliability of the remote plasma source. In addition, this design complements the function of the regulating electrode pair 6. The regulating electrode pair 6 generates a deflection electric field to drive the charged particles to change direction, while the guide 7 guides the entire airflow to change direction through its physical structure. This dual protection mechanism can more effectively control the trajectory of the airflow and charged particles, further improving the performance and reliability of the system.

[0058] The airflow guide 7 can be made of various shapes and materials to achieve its function. For example, the airflow guide surface 701 can be arc-shaped or beveled to smoothly guide the airflow direction, and can also be designed as a smooth surface or a microstructured surface to optimize the airflow guiding effect. As for the material of the airflow guide 7, high-temperature resistant and corrosion-resistant materials such as ceramics, quartz or special alloys can be selected.

[0059] In some embodiments, the flow guide 7 is partially or entirely made of non-conductive ceramic. Making the flow guide 7 of non-conductive ceramic has the following advantages: improved durability, enhanced insulation, reduced contamination, and improved flow guidance effect. Non-conductive ceramic has excellent high-temperature resistance and corrosion resistance, allowing it to remain stable in harsh plasma environments for extended periods, thus extending the service life of the flow guide 7. Non-conductive ceramic is a good electrical insulator, preventing unnecessary current from being generated between the flow guide 7 and the plasma, ensuring plasma stability. Non-conductive ceramic is less likely to react with plasma, reducing plasma contamination and ensuring plasma purity. Ceramic materials can be precisely machined into the required flow guiding shape, achieving better airflow guidance. By using non-conductive ceramic to make the flow guide 7, the problems of easy corrosion and reaction with plasma in the plasma environment can be effectively solved. This design not only extends the service life of the flow guide 7 but also improves the overall performance and stability of the plasma source. Simultaneously, due to the insulating properties of ceramic materials, the flow guide 7 can also avoid adverse effects on the electric field distribution of the plasma, further ensuring the uniformity and stability of the plasma.

[0060] The flow guide 7 can be made entirely of non-conductive ceramic or partially of non-conductive ceramic. When made entirely of non-conductive ceramic, the entire flow guide 7 exhibits excellent corrosion resistance and insulation. When partially made of non-conductive ceramic, non-conductive ceramic can be used only on the surfaces in direct contact with the plasma, while other materials, such as metals, can be used internally to improve the strength and thermal conductivity of the flow guide 7.

[0061] The choice of non-conductive ceramics depends on the specific application environment. Commonly used non-conductive ceramic materials include alumina (Al2O3), aluminum nitride (AlN), and zirconium oxide (ZrO2). For example, alumina has excellent high-temperature resistance and can be used in high-temperature environments above 1500℃; aluminum nitride has good thermal conductivity, which can help dissipate heat; and zirconium oxide has excellent thermal shock resistance.

[0062] The dimensions and angle of the flow guide 7 can be optimized based on the size of the annular vacuum chamber 1 and the airflow characteristics. These parameters can be determined through computational fluid dynamics simulations and experimental tests to determine their optimal values.

[0063] The synergistic effect of the flow guide 7 and the regulating electrode pair 6 is manifested in the following ways: the flow guide 7 mainly affects the overall airflow direction, while the regulating electrode pair 6 provides fine control over charged particles. After the airflow initially changes direction after passing through the flow guide 7, the regulating electrode pair 6 can further fine-tune the trajectory of the charged particles, allowing them to better avoid the cavity wall. This dual effect not only improves the control accuracy of charged particles but also enhances the system's adaptability to different operating conditions.

[0064] Preferably, the flow guide 7 is detachable. This detachable design allows the flow guide 7 to be easily removed from the connecting cavity 102. This design improves the maintainability and flexibility of the flow guide 7. By adopting a detachable design, the flow guide 7 can be easily removed and replaced as needed. This facilitates cleaning, maintenance, or replacement of the flow guide 7 without disassembling the entire cavity structure. Simultaneously, flow guides of different shapes or materials can be used to meet different process requirements, improving the system's adaptability and flexibility. The detachable design also facilitates fine-tuning of the flow guide 7. Operators can remove the flow guide 7 for fine-tuning to optimize airflow guidance. This helps improve plasma uniformity and stability. In summary, the detachable flow guide 7 design improves the maintainability, flexibility, and performance adjustability of the remote plasma source cavity, which is beneficial for extending equipment life and meeting different process requirements.

[0065] The detachable flow guide 7 can be implemented in several ways. A common method is bolt fixing. Screw holes are pre-drilled on the outer wall of the connecting cavity 102, and corresponding bolt holes are provided on the flow guide 7. The flow guide 7 is then fixed to the connecting cavity 102 using bolts. This method is simple to operate and easy to install and remove. Another method is a snap-fit ​​structure. Grooves are provided on the inner wall of the connecting cavity 102, and corresponding protrusions are provided on the edge of the flow guide 7. Quick installation and removal are achieved through snap-fit. Alternatively, magnetic adsorption can be used. Magnets are embedded in the inner wall of the connecting cavity 102, and the flow guide 7 is made of magnetic material, allowing it to be fixed by magnetic attraction.

[0066] In some implementations, see Figure 4 The air inlet 2 and the air outlet 3 are along a characteristic straight line (such as...) Figure 4 The straight line c) in the figure connects the opposite sides of the annular vacuum cavity 1. The annular vacuum cavity 1 is symmetrical about this feature line, and the magnetic core assembly 4 is symmetrically distributed about this feature line.

[0067] This structural layout optimizes the performance of the remote plasma source cavity. The inlet 2 and outlet 3 are arranged along a characteristic straight line connecting opposite sides of the annular vacuum cavity 1. This arrangement ensures more uniform and stable gas flow within the cavity, which is beneficial for plasma generation and maintenance. The annular vacuum cavity 1 is symmetrical about the characteristic straight line; this design allows for more uniform gas distribution within the cavity, reducing dead zones and eddies, thereby improving plasma uniformity. The magnetic core assembly 4 is symmetrically distributed about the characteristic straight line; this layout generates a more uniform magnetic field, contributing to plasma stability and uniformity, while also improving energy utilization efficiency.

[0068] The characteristic straight line can be a virtual reference line, typically coinciding with the axis of symmetry of the annular vacuum cavity 1. The inlet 2 and outlet 3 can be located on two opposing straight channels 101 of the annular vacuum cavity 1, with their centerlines coinciding with the characteristic straight line. This arrangement ensures that the gas path from inlet 2 to outlet 3 is minimized, reducing the gas's residence time within the cavity and improving plasma generation efficiency.

[0069] For example, in one specific implementation, see Figures 1-4 The annular vacuum chamber 1 includes four straight channels 101. The four straight channels 101 include two parallel first straight channels 1011 and two parallel second straight channels 1012. The first straight channels 1011 and the second straight channels 1012 are perpendicular and the first straight channels 1011 is shorter than the second straight channels 1012. The air inlet 2 and the air outlet 3 are respectively connected to the two first straight channels 1011. The magnetic core assembly 4 is wound on the two second straight channels 1012.

[0070] The arrangement of four straight cavities 101 forms a closed-loop flow channel, with two shorter first straight cavities 1011 for gas inlet and outlet, and two longer second straight cavities 1012 for plasma generation. The inlet 2 and outlet 3 are connected to the two first straight cavities 1011 respectively; this design ensures uniform gas distribution and flow within the cavity. Magnetic core assemblies 4 are wound around the two second straight cavities 1012. These magnetic core assemblies 4 generate magnetic fields, which aid in plasma generation and confinement. The first straight cavities 1011 and second straight cavities 1012 are arranged perpendicularly; this arrangement reduces gas flow resistance and also facilitates magnetic field distribution. The first straight cavities 1011 are shorter than the second straight cavities 1012; this design provides more installation space for the magnetic core assemblies 4 while ensuring efficient gas inlet and outlet, allowing for a longer path for plasma generation and improving plasma generation efficiency.

[0071] In this document, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, without necessarily requiring or implying any such actual relationship or order between these entities or operations.

[0072] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A remote plasma source cavity, comprising an annular vacuum cavity (1), an air inlet (2), an air outlet (3), a magnetic core assembly (4), and an ignition coil (5); characterized in that, The annular vacuum cavity (1) includes multiple straight channels (101) connected end to end to form a closed loop flow channel. The magnetic core assembly (4) is wound on at least one of the straight channels (101). The air inlet (2) and the air outlet (3) are respectively connected to two different straight channels (101). An adjustment electrode pair (6) is provided at the connection of any two adjacent straight channels (101). The adjustment electrode pair (6) is used to generate a deflection electric field to drive the charged particles in the airflow to turn so as to avoid the charged particles from contacting the circumferential sidewall of the annular vacuum cavity (1). Any two adjacent linear channels (101) are connected by a connecting channel (102), and the adjustment electrode pair (6) is disposed at the connecting channel (102); A flow guide (7) is provided on the inner surface of the outer peripheral sidewall at the connection between the connecting cavity (102) and the upstream adjacent straight cavity (101). A flow guide surface (701) is provided on the inward side of the flow guide (7), and the flow guide surface (701) is used to guide the airflow to change direction.

2. The remote plasma source cavity according to claim 1, characterized in that, The regulating electrode pair (6) includes a positive electrode plate (601) and a negative electrode plate (602) arranged opposite to each other. The positive electrode plate (601) is disposed on the outer circumferential sidewall of the annular vacuum cavity (1), and the negative electrode plate (602) is disposed on the inner circumferential sidewall of the annular vacuum cavity (1).

3. The remote plasma source cavity according to claim 1, characterized in that, The connecting cavity (102) is a straight cavity.

4. The remote plasma source cavity according to claim 1, characterized in that, The connecting cavity (102) is a curved cavity.

5. The remote plasma source cavity according to claim 1, characterized in that, The flow guide (7) is made partly or entirely of non-conductive ceramic.

6. The remote plasma source cavity according to claim 1, characterized in that, The flow guide (7) is detachable.

7. The remote plasma source cavity according to claim 1, characterized in that, The air inlet (2) and the air outlet (3) are connected along a characteristic straight line to opposite sides of the annular vacuum cavity (1). The annular vacuum cavity (1) is symmetrical about the characteristic straight line, and the magnetic core assembly (4) is symmetrically distributed about the characteristic straight line.

8. The remote plasma source cavity according to any one of claims 1-7, characterized in that, The annular vacuum cavity (1) includes four straight channels (101), which include two parallel first straight channels (1011) and two parallel second straight channels (1012). The first straight channels (1011) are perpendicular to the second straight channels (1012), and the first straight channel (1011) is shorter than the second straight channel (1012). The air inlet (2) and the air outlet (3) are respectively connected to the two first straight channels (1011). The magnetic core assembly (4) is wound on the two second straight channels (1012).

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