Plasma processing and upper electrode integrated cooling system and method

Abstract

The invention discloses plasma processing equipment and an upper electrode integrated cooling system and method, and is applied to the technical field of semiconductor manufacturing equipment. The cooling system comprises an air source supply device, a pure pneumatic airflow supercharging device without moving parts and a swirling flow field generating device. Initial air flow required by cooling forms high-speed spiral air flow covering the surface of the cavity cover after being pressurized and accelerated by the air flow, so that efficient and uniform severe convection heat dissipation is realized. Therefore, the mechanical vibration is thoroughly eliminated, the stability and precision of the etching process are remarkably improved, the structure is compact, and the reliability is high.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing equipment technology, specifically to a plasma processing device and an integrated cooling system and method for the upper electrode. Background Technology

[0002] Plasma etching is a key process in chip manufacturing. For example, inductively coupled plasma (ICP) equipment generates a lot of heat during the process, causing the temperature of the equipment chamber, especially the upper electrode area, to rise sharply.

[0003] Currently, the mainstream temperature control method involves installing a fan at the top of the chamber and heating wires at the bottom. When high temperatures occur, heating is stopped and the fan speed is increased to force air cooling.

[0004] However, using fans for forced air cooling not only has a limited cooling effect, but more importantly, the fans generate vibrations during operation. These vibrations interfere with the plasma and wafers during the processing, affecting the stability and precision of the etching process, especially in current submicron and more advanced processes. Summary of the Invention

[0005] The primary objective of this invention is to overcome the inherent defects of the prior art and provide an integrated cooling solution for the upper electrode. Its core objective is to achieve efficient and uniform heat dissipation of the electrode cavity cover on the ICP etching equipment under the premise of completely eliminating mechanical vibration sources.

[0006] This invention provides an integrated cooling system for the upper electrode, comprising: An air supply unit is used to provide the initial airflow required for cooling; A purely pneumatic airflow booster device, the air inlet of which is connected to the air supply device, the internal structure of which is configured to use the kinetic energy of the initial airflow to entrain and mix the air in the environment to be cooled, thereby outputting a boosted airflow with a flow rate greater than that of the air inlet. A swirling flow field generating device includes a accommodating chamber and an airflow guiding structure disposed within the accommodating chamber; the inlet of the accommodating chamber is in fluid communication with the outlet of the airflow boosting device, and multiple airflow outlets are provided on its wall; the airflow guiding structure is configured to guide the incoming boosted airflow, so that multiple airflows discharged from the multiple airflow outlets interact within a confined space inside the accommodating chamber to form a synthetic airflow with a three-dimensional spiral trajectory, used for sweeping heat dissipation on the wall surface of the confined space.

[0007] Preferably, the airflow guiding structure includes at least one guide surface that is not parallel to the initial flow direction of the pressurized airflow, and the guide surface is configured to impart a velocity component to the pressurized airflow perpendicular to its initial flow direction.

[0008] Preferably, the guide surface is a plane or a curved surface, and the angle formed between it and the initial flow direction of the pressurized airflow is in the range of 15° to 60°.

[0009] Preferably, the included angle is between 25° and 35°.

[0010] Preferably, in any one of the upper electrode integrated cooling systems of the present invention, the number of airflow guiding structures is multiple and they are arranged circumferentially around the central axis of the accommodating chamber, so that the airflow discharged from the multiple circumferentially distributed airflow outlets generates a resultant torque around the central axis, thereby driving the resultant airflow to rotate. And / or, the gas supply device includes a duct that communicates with the heat dissipation vent of the radio frequency matching unit of the plasma processing equipment; And / or, the accommodating chamber is integrally formed or fixedly connected to the cavity cover structure of the upper electrode of the plasma processing device, such that the confined space is the space formed by the inner surface of the cavity cover and a covering member; And / or, the accommodating chamber also integrates a process gas distribution function, and its interior is provided with a flow channel that guides the process gas to a spray head; And / or, the plurality of airflow outlets are non-uniformly distributed on the walls of the accommodating chamber, and their distribution density is set according to the expected heat load distribution of the confined space walls; And / or, the airflow booster includes an air amplifier, the air amplifier including an annular nozzle and a diffuser chamber communicating with the annular nozzle.

[0011] The present invention also provides a temperature control method for a plasma processing device, applied to the upper electrode region of the device, the method comprising: Provide an initial airflow required for cooling; The initial airflow is accelerated and its flow rate is amplified to generate a pressurized airflow; By guiding the pressurized airflow through multiple air outlets into a confined space, the pressurized airflow is guided to impact one or more guide surfaces, causing the flow direction of the pressurized airflow to be deflected. Then, multiple airflows couple within the confined space, spontaneously forming a composite airflow with a three-dimensional spiral motion. The combined airflow is used to perform sweeping heat dissipation on the walls of the confined space.

[0012] Preferably, the outflow direction of each airflow outlet is matched and set according to the fixed tilt angle of the guide surface.

[0013] Preferably, the initial airflow originates from the cooling airflow of the radio frequency matching unit of the plasma processing equipment.

[0014] The present invention also provides a plasma processing device, including a reaction chamber and an upper electrode, wherein the upper electrode integrates an upper electrode integrated cooling system as described in any one of the present invention.

[0015] Preferably, the plasma processing equipment includes an inductively coupled plasma etching device.

[0016] The present invention, through the implementation of the above-mentioned technical concept, brings about unexpected technical effects: Fundamental vibration-free advantage: Due to the use of a pure pneumatic structure throughout the process, the interference of motor vibration on plasma and wafers is completely eliminated, fundamentally improving the stability and precision of the etching process, especially suitable for submicron and more advanced processes.

[0017] Revolutionary improvement in heat dissipation performance: Through pressurization and acceleration, the effective airflow rate is significantly increased; moreover, the spiral airflow pattern greatly enhances the convective heat transfer efficiency between the airflow and the wall. Experiments show that, under the same heat load, the solution of this invention can reduce the maximum temperature of the cavity cover by more than 30%.

[0018] Excellent heat dissipation uniformity: The self-uniformity of the spiral airflow ensures an extremely uniform temperature distribution on the cavity cover surface, with the temperature difference controllable within ±2°C, effectively avoiding device damage and process drift caused by uneven thermal stress.

[0019] High integration: The system can be directly integrated into the existing upper electrode structure. For example, the air duct can simultaneously serve the functions of guiding etching gas and accommodating RF coils, resulting in a compact integrated design.

[0020] High reliability and low cost: The cooling solutions have no moving parts, resulting in less wear and tear on components, longer lifespan, and significantly reduced maintenance costs and failure rates. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the vertical cross-section of the upper electrode integrated cooling system in this invention, showing the direction of the spiral airflow. Figure 2 This is a three-dimensional structural diagram of the upper electrode integrated cooling system in this invention; Figure 3 This is a schematic diagram of the bottom side structure of the upper electrode integrated cooling system in this invention; Figure 4 This is a vertical cross-sectional view of the ICP etching reaction chamber that integrates the upper electrode integrated cooling system described in this invention. Figure 5This is a schematic diagram of temperature control based on the upper electrode integrated cooling system in this invention; Explanation of reference numerals in the attached figures: 1: Exhaust Vent; 2: Buffle; 3: Air Hole; 5: Match; 6: Air Duct; 7: Air Pressure Booster; 8: Flange; 9: Plump Chamber; 10: Radio Coil; 11: Shower Head; 12: Heater; 13: Gasinet Nozzle; 14: Upper Chamber; 15: Lower Chamber. Detailed Implementation

[0022] The implementation of the technical solution of the present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0023] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0024] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments can be combined with each other. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that various aspects of embodiments within the scope of the appended claims are described below. It will be apparent that the aspects described herein can be embodied in a wide variety of forms, and any particular structure and / or function described herein is merely illustrative. Based on this invention, those skilled in the art will understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects set forth herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using structures and / or functionalities other than one or more of the aspects set forth herein.

[0026] It should also be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. The drawings only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0027] Additionally, specific details are provided in the following description to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that practice can be carried out without these specific details.

[0028] Traditional cooling solutions generally include air cooling and liquid cooling. In the current cooling of ICP equipment, air cooling with forced cooling by fans is usually used.

[0029] Fan-cooled cooling generally has the following obvious drawbacks: First, the fan has low heat dissipation efficiency, especially under high power heat load, the cooling air tends to spread in all directions, the actual contact heat dissipation area is insufficient, resulting in local overheating; second, the vibration generated by the fan motor during operation will be transmitted to the upper electrode in the ICP equipment, causing plasma instability and wafer micro-displacement, affecting the etching effect and reducing product yield.

[0030] To overcome the above-mentioned defects, the inventors also tried to use water-cooled and air-cooled structures, and found that water-cooled systems are relatively complex and prone to leakage, while ordinary air-cooled structures have poor airflow organization and uneven heat dissipation.

[0031] Therefore, an efficient, stable, and vibration-free cooling solution is particularly important for addressing the need for cooling the upper electrode.

[0032] However, after further analysis, the inventors discovered that the root cause of the two deep-rooted defects in the traditional fan cooling solution is not simply insufficient heat dissipation efficiency, but rather stems from the following contradiction between its physical principles and mechanical structure within the etching equipment: On the one hand, there is an inherent contradiction between heat dissipation efficiency and uniformity: fan cooling is a form of "overflow scouring," with poor airflow directionality, easily forming turbulence and eddies on the cavity cover surface, leading to uneven airflow distribution. High-speed airflow tends to flow along paths of least resistance, rather than towards areas that most require heat dissipation. When blowing onto a flat electrode plate surface, the airflow cannot adhere tightly to the surface, causing "airflow short-circuiting" and localized heat accumulation. Therefore, simply increasing the fan speed cannot effectively increase the heat dissipation area; on the contrary, it may lead to a smaller effective heat dissipation area, exacerbating uneven heat dissipation and causing localized heat accumulation problems.

[0033] Secondly, there is a fundamental conflict between vibration and plasma stability: mechanical vibration is unavoidable during fan motor operation, especially when high speeds are required to provide a large airflow for strong cooling. The vibration generated by the fan is directly transmitted through the fan base and equipment structure to the upper electrode (especially the RF coil and ceramic plate) and wafer stage, which are the core of plasma excitation, causing two problems: First, the vibration interferes with the electromagnetic field, causing fluctuations in plasma density and affecting the uniformity of etching rate; second, it causes micron-level displacement of the electrostatic chuck or stage supporting the wafer, directly leading to wafer micro-displacement, affecting the linewidth control accuracy of the etching pattern, and in severe cases, causing the etching linewidth (CD) to go out of control, and even leading to a significant decrease in the yield of advanced processes.

[0034] In addition, improving heat dissipation efficiency depends entirely on increasing motor power and blade speed, which will obviously amplify vibration and noise problems, further exacerbating the aforementioned contradictions.

[0035] Therefore, how to achieve efficient and uniform active heat dissipation on the surface of the upper electrode without introducing mechanical vibration is a key technical direction that this invention needs to consider.

[0036] To achieve the above objectives, this invention breaks through the traditional mindset of reducing fan volume and proposes a novel cooling technology concept of "using air to drive air, creating swirling airflow." It should be noted that this technological concept stems from an in-depth analysis of the root cause of the problem.

[0037] For example, regarding the issue of vibration: since vibration has a serious impact on the process, any form of electric component that generates vibration must be eliminated.

[0038] In other words, during the design phase, it is necessary to eliminate vibrations generated by components. Therefore, the technical concept must abandon the form of electric components that generate vibrations and adopt pure pneumatic components as the core power source, so as to fundamentally cut off the source of vibration.

[0039] For example, regarding the issues of heat dissipation efficiency and uniformity: improving heat dissipation efficiency requires increasing fan speed, which in turn generates more noticeable vibrations, making the uniformity problem more prominent. Inspired by the efficient energy transfer capabilities of tornadoes in nature, this invention proposes artificially creating a stable and controllable spiral airflow field (i.e., the "tornado effect") within a confined space. This airflow field achieves the following objectives: first, strong convection: the spiral airflow sweeps rapidly along the surface of the cavity cover, continuously carrying away heat; the convective heat transfer coefficient is much higher than that of disordered turbulence. Second, self-uniformity: the rotating airflow has a centrifugal tendency, automatically spreading outwards, thus forcing heat to distribute evenly from the center outwards, avoiding localized overheating.

[0040] In summary, the core technical concept of this invention lies in forming a controllable airflow (i.e., a tornado-effect airflow) to quickly and evenly remove heat and achieve cooling.

[0041] Therefore, this invention adopts the pure fluid dynamics concept of "aerodynamic amplification" (or "aerodynamic power generation"), and its core principle and technical path can be broken down as follows: On the one hand, in terms of energy conversion pathways: the pressure energy / kinetic energy of the airflow is converted into airflow with higher kinetic energy; Secondly, regarding airflow input: an initial airflow with a certain amount of energy (which can be an existing low-vibration source of air from the equipment, such as the cooling air from the RF matching unit). In three aspects, the core principle and execution action are as follows: the principle of fluid mechanics is used to make the initial airflow act as a "funnel" to attract, drive or even accelerate a large amount of still or slow-moving air around the surface of the upper electrode that needs to be cooled. Fourthly, regarding the final airflow output: a stronger cooling airflow with significantly amplified flow rate and momentum.

[0042] In terms of implementing the technical concept of this invention, an initial airflow is accelerated into a high-speed jet form through an annular nozzle. This high-speed jet form of the initial airflow will form a low-pressure zone (vacuum effect) at the nozzle outlet. This low-pressure zone is like an invisible "suction cup" that naturally draws in the ambient air around the area that needs to be cooled. The drawn-in air mixes with the high-speed jet in the mixing chamber, gains energy, and then smoothly decelerates and restores pressure in the diffuser chamber, ultimately forming a high-flow-rate, high-momentum output airflow.

[0043] Since no mechanical vibration components are involved in the entire cooling process, no mechanical vibration is generated, thus preventing the impact of mechanical vibration at its source. Furthermore, the output airflow can quickly remove heat, and the heat is evenly diffused outwards to achieve uniform heat dissipation.

[0044] Traditional fan cooling relies on the idea of ​​using a fan to generate cooling airflow. It depends on mechanical moving parts such as electric motors and rotating blades to create cooling airflow. Its inherent defects of vibration and poor airflow organization have become a bottleneck for high-precision semiconductor manufacturing equipment.

[0045] The present invention breaks away from this mindset and adopts a purely pneumatic "air-driven air" approach. Instead of directly "creating wind", it cleverly "borrows wind to generate wind", using a small airflow as an energy seed and amplifying and shaping it through an ingenious fluid structure. This eliminates vibration while actively controlling the airflow pattern (generating a spiral flow), ultimately achieving efficient and uniform heat dissipation. This is the core of the present invention.

[0046] The core innovation of this invention lies in generating and controlling a highly efficient airflow (spiral airflow) based entirely on a passive, pre-defined physical structure, achieving reliable heat dissipation without the need for sensors or complex controls.

[0047] In addition to replacing fans in heat dissipation applications, this invention can also be applied to some other common applications.

[0048] For example, in applications where the process is extremely sensitive to vibration: even if the fan vibration has a small impact, in some high-precision processes at the atomic level, any vibration may affect the process. The present invention adopts a pure pneumatic solution as a vibration-free cooling solution, which will well meet the heat dissipation requirements of special vibration-free process scenarios.

[0049] For example, in applications where the risk of liquid leakage needs to be avoided: for some special material processes, the primary task is to absolutely eliminate the risk of coolant leakage. This invention uses a pure pneumatic solution to replace the liquid cooling solution, which will well meet the heat dissipation requirements without liquid leakage.

[0050] For example, in applications where equipment simplification is required: traditional liquid cooling systems require numerous components such as water pumps, water pipes, and chillers, resulting in complex cooling system structures, high costs, and inconvenient maintenance. In contrast, this invention uses a pure pneumatic solution as a simplified alternative, which significantly reduces equipment complexity, construction costs, maintenance difficulty, and expenses.

[0051] The present invention will now be described in detail with reference to the accompanying drawings and through several embodiments. These embodiments are intended to fully disclose the present invention so that those skilled in the art can implement it, but the scope of protection of the present invention is not limited thereto.

[0052] Example 1: System Core Architecture and Swirl Generation like Figures 1-4 As shown in the figure, this embodiment illustrates the basic architecture of the cooling system of the present invention. The three core units of the system and their collaborative operation are illustrated below.

[0053] Air supply device: In this embodiment, the heat dissipation vent of the existing RF matching unit 5 is directly used as the air source for the initial airflow. The airflow here is usually filtered clean room temperature air, which can be used directly, realizing resource reuse. In practice, the air supply device inputs the initial airflow to the pure pneumatic airflow booster device 7 through the air duct 6 (AIR DUCT).

[0054] Pure pneumatic airflow booster device 7: Preferably an air amplifier, so that the initial airflow from the air duct 6 (air duct 6) (e.g., pressure 0.5 MPa, flow rate 50 L / min) enters the annular nozzle of the air amplifier, is accelerated to form a high-speed jet, and this jet generates a strong entrainment effect at the outlet, drawing a large amount of ambient air (e.g., about 10 times the initial flow rate) into the mixing chamber. The mixed airflow decreases in velocity and recovers in pressure within the conical diffuser chamber, finally outputting a boosted airflow, for example, with a pressure of about 0.1 MPa and a flow rate increased to about 550 L / min. It should be noted that this process has no moving mechanical parts, eliminating vibration at its source.

[0055] The swirling flow field generating device consists of a accommodating chamber 9 (i.e., an air duct chamber) and four fixed, inclined airflow guiding structures 2 (preferably baffle structures) inside it. The inlet of the accommodating chamber 9 is fluidly connected to the outlet of the airflow booster 7 (preferably, a flange seat 8 is used for direct connection between the airflow booster 7 and the air duct chamber, acting as a bridge between the air duct and the air duct chamber). The walls of the accommodating chamber 9 are also equipped with multiple airflow outlets 3 (air holes) and exhaust vents 1 (exhaust vents, located on the side wall of the air duct chamber, facilitating the rapid discharge of high-speed, low-pressure airflow generated by the tornado effect). The airflow guiding structures 2 are configured to guide the incoming pressurized airflow, causing multiple streams of airflow discharged from the multiple airflow outlets 3 to interact within a confined space inside the accommodating chamber 9, forming a synthetic airflow with a three-dimensional spiral trajectory.

[0056] Specifically, after the pressurized airflow enters the air duct chamber, it impacts the baffles. The inclined surface (guide surface) of each baffle decomposes the airflow, giving it a strong tangential velocity component. The four airflows ejected from the four circumferentially distributed airflow outlets 3, due to their consistent tangential velocity direction, couple and reinforce each other within the confined space formed by the cavity cover and the upper cover, spontaneously forming a three-dimensional spiral composite airflow that rotates at high speed around the central axis and diffuses in all directions. This airflow, like an "invisible hand," sweeps at high speed along the inner surface of the cavity cover, achieving efficient and uniform strong convective heat transfer.

[0057] Under a 20kW plasma load, the experimental data were compared as follows: the cooling effect of the present invention was as follows: the average temperature of the cavity cover surface was 60℃, and the maximum temperature difference ΔT < 3℃; the cooling effect of the comparative example (i.e., the conventional fan cooling example) was as follows: the average temperature of the cavity cover surface was 85℃, ΔT > 15℃, and obvious plasma scintillation could be observed (due to fan vibration).

[0058] Example 2: Optimization of the shape and angle of the guide surface This embodiment delves into the specific implementation of the airflow guiding structure, providing examples of different shaped guiding surfaces.

[0059] Example 1 uses a planar baffle structure: planar baffles are simple to manufacture and low in cost. This example uses a simple inclined flat plate as a baffle to form the airflow guiding structure 2. The baffles inside the air duct are arranged at an angle (here, inclination means forming an angle with the direction of the pressurized airflow), for example, four baffles (BAFFLE) at an angle of 30° are evenly distributed around the circumference, and there are four airflow outlets 3 around the center that spray pressurized airflow toward the baffles. After the high-speed airflow hits the baffles, it changes direction. Multiple airflows interact to form a clockwise spiral composite airflow (shown by the purple dotted line), and finally it is discharged from the exhaust vents 1 set on the four sides of the air duct.

[0060] During implementation, when setting up the baffles, the angle between the baffles and the initial flow direction of the pressurized airflow can be tested and adjusted. This angle is preferably in the range of 15° to 60°, and more preferably in the range of 25° to 35°.

[0061] Example 2 uses a baffle structure with a curved guide surface: the guide surface of the baffle is designed as a concave parabolic surface, which can better converge the airflow and reduce energy loss.

[0062] Actual measurements showed that, at α=30°, curved guide vanes can increase the outlet airflow velocity by about 8% compared to flat guide vanes, but the processing complexity increases.

[0063] Optimal angle example of included angle α: Using the two examples above, tests were conducted on the planar guide vane at different tilt angles, where α = 15°, 20°, 25°, 30°, 35°, 40°, 45°, and 60°. The test results showed that: When α < 25°, the airflow deflection is slightly weaker, the given tangential velocity component is smaller, thus forming a weaker spiral flow field. The heat dissipation in the central region is slightly weaker, but it can still meet the heat dissipation requirements.

[0064] When α>35°, the airflow impact resistance is slightly larger, the total pressure loss increases significantly, the swirling flow is stronger, the overall air volume and sweeping speed decrease, and the overall heat dissipation effect gradually weakens.

[0065] An unexpected finding was that, within the range of 25° to 35°, especially near 30°, the system achieves an optimal balance between swirling intensity and flow resistance. At this angle, the helical flow field is stable and has a wide coverage, and the temperature uniformity of the cavity cover surface is optimal (ΔT is minimized).

[0066] In summary, for different heat dissipation requirements, planar or curved baffle structures can be preferred, and different heat dissipation effects can be achieved by adjusting the tilt angle of the baffles (i.e., the angle between the baffle and the airflow direction) to meet actual heat dissipation needs.

[0067] Example 3: Synergistic Example of Multiple Flow Guide Structures This embodiment provides different examples and comparative analyses of how multiple airflow guiding structures 2 can achieve synergistic effects in different circumferential arrangements.

[0068] Example 1 (Example of the present invention): The four baffles are evenly distributed around the circumference and have the same tilt direction (all of which cause the airflow to generate a clockwise tangential velocity).

[0069] Example 2 (Comparative Example): Only two symmetrically distributed baffles are set up, that is, two baffles are symmetrically arranged on both sides of the circumferential diameter, so as to guide and deflect the pressurized airflow using the two baffles.

[0070] Example 3 (Comparative Example): Four baffles are arranged on the circumference, with two guides set to clockwise and the other two to counterclockwise, so that the two sets of baffles with different guide deflections work together.

[0071] Test Results: Example 1 effectively guides the pressurized airflow, resulting in a stable and strong unidirectional rotating composite airflow field with excellent symmetry. Example 2 only partially guides the pressurized airflow, leading to an asymmetrical composite airflow field and slightly worse heat dissipation than Example 1. Dead zones may also appear in heat dissipation when the baffles are too small or too far apart. Example 3 has the worst heat dissipation effect because the guiding effect of the baffles on the pressurized airflow may cancel each other out, preventing the formation of vortex flow and essentially degenerating into disordered turbulence.

[0072] This embodiment demonstrates that "multiple guide structures generating tangential velocity components in the same direction" is crucial for generating an effective spiral flow field for uniform heat dissipation over a large area, and its effect is far more than the simple superposition of the effects of a single or multiple uncoordinated flow guide structures.

[0073] In summary, the number of airflow guiding structures 2 (preferably baffles) is preferably multiple, and they are arranged circumferentially around the central axis of the accommodating chamber 9. This allows the pressurized airflow discharged from the multiple circumferentially distributed airflow outlets 3 to generate a resultant torque around the central axis, thereby driving the resultant airflow to rotate. In a preferred example, the guide surfaces of the multiple airflow guiding structures 2 have the same inclination direction, which further promotes the unidirectional rotation of the resultant airflow, forming a rotating flow field with better heat dissipation performance.

[0074] Example 4: All components of the system are made of non-magnetic materials. In semiconductor equipment, it is crucial to avoid any unnecessary interference with the plasma. In this embodiment, all key components of the cooling system, including air ducts, air amplifiers, flange seats, air duct chambers, baffles, etc., are made of high-strength aluminum alloy or ceramic-coated aluminum alloy.

[0075] Since all components are made of non-magnetic materials, eddy current effects or disturbances to the magnetic field distribution can be avoided in strong radio frequency electromagnetic fields, thus ensuring extremely uniform and stable plasma excitation and distribution, making the cooling system have minimal impact on the plasma environment. In particular, in nanoscale etching precision applications, using non-magnetic materials for each component of the cooling system is a subtle but crucial implementation method.

[0076] Example 5: Airflow booster device and air source connection example This embodiment describes in detail a preferred implementation of the purely pneumatic airflow booster device 7—an air amplifier, such as a Coanda effect air amplifier.

[0077] As the core component of the purely pneumatic airflow booster device 7, the air amplifier can preferably be a commercially available product or an improved product as illustrated below.

[0078] An air amplifier may include components such as an annular nozzle, a suction chamber, and a diffuser chamber.

[0079] Among them, the annular nozzle is preferably made of high-precision wear-resistant material, and the annular gap can be very small, such as 0.1mm. When the initial airflow passes through this small gap, the airflow speed can be accelerated to a very high speed, such as Mach number 1.5 or higher.

[0080] Entrainment chamber: The high-speed jet forms a vacuum in the entrainment chamber. The area of ​​the entrainment port can be designed according to the maximum amount of ambient air entrained with the minimum pressure loss, and is not limited here.

[0081] The diffuser chamber adopts a conical design with an expansion angle of less than 10°, such as 8°, to ensure that the mixed airflow can smoothly decelerate and pressurize, effectively converting kinetic energy into pressure energy.

[0082] Furthermore, the entire air amplifier unit can be sealed with O-rings, providing excellent sealing performance and facilitating the formation of pressurized airflow. Additionally, the unit requires no lubrication and has an extremely long maintenance cycle.

[0083] In some instances, by making the gap of the annular nozzle adjustable, it is possible to flexibly adapt to different flow and pressure requirements.

[0084] For example, to adapt to different process formulations (such as heat dissipation requirements under different power levels), the annular nozzle of the air amplifier has been improved to make its gap adjustable. The specific structure is as follows: the position of the nozzle inner core is adjusted by rotating a threaded sleeve with micron-level precision, thereby changing the width of the annular gap, preferably within the range of 0.05mm-0.2mm.

[0085] Therefore, when a large volume of air with relatively low pressure is required, the gap can be increased; when a higher pressure airflow with strong penetrating power is required, the gap can be decreased. This adjustable gap greatly enhances the cooling system's adaptability to process requirements and energy efficiency needs.

[0086] In some instances, the air duct 6 is connected to the heat dissipation vent of the RF matching unit 5 via a quick-connect fitting, such as a quick-connect self-sealing connector. Therefore, by optimizing the connection between the air supply device and the RF matching unit 5 vent, the air duct can be disconnected and reconnected within seconds without tools when maintenance or replacement of the matching unit is required, significantly reducing equipment downtime and increasing equipment productivity.

[0087] Example 6: Integration and Optimization of the Receptacle Chamber In some examples, the chamber is integrated with the upper electrode. In this embodiment, the accommodating chamber 9 (air duct chamber) is not a separate part, but is integrated into the metal chamber cover body of the upper electrode by casting. This integrated structure is compact, saves space, and is often suitable for layout within space-constrained equipment cavities. Furthermore, the integrated structure has excellent rigidity, avoiding the micro-motion and vibration transmission paths that may exist between separate components. Additionally, the integrated structure has high thermal conductivity, allowing heat to be directly conducted from the chamber cover wall to the air duct chamber wall and carried away by the cooling airflow flowing inside.

[0088] In some examples, the accommodating chamber 9 also integrates a process gas distribution function, with an internal flow channel guiding the process gas to a spray head 11. In implementation, the air duct chamber is designed with a double-layer hollow structure: the lower layer is the process gas flow channel, receiving the etching gas from the inlet nozzle 13 (GASINLET NOZZLE, used to directionally inject etching gas to the key area of ​​the reaction chamber), and distributing it evenly to the spray head 11 below through a flow equalization plate; the upper cavity serves as a cooling airflow channel, performing the spiral airflow generation and discharge functions described in this invention.

[0089] By integrating it into a double-layer hollow structure, two key functions (process gas distribution and electrode cooling) are integrated into the same core component, which greatly simplifies the mechanical structure of the upper electrode, reduces potential leakage points, lowers manufacturing costs and assembly complexity, and realizes the modular and integrated design of the equipment.

[0090] In some examples, multiple air outlets 3 are non-uniformly distributed on the accommodating chamber 9, and their distribution density is adjusted according to the expected heat load distribution of the confined space wall. Preferably, the distribution density of air outlets 3 is greater in areas with higher expected heat load than in areas with lower expected heat load, thereby optimizing the heat dissipation effect through non-uniform air outlet distribution.

[0091] It should be noted that during the operation of the upper electrode, due to the uneven shape of the RF coil 10 and the uneven plasma distribution, the heat load on the cavity cover surface is not uniformly distributed. Typically, the heat flux density is higher in the central region and near the coil turns. Therefore, this embodiment optimizes the distribution of the airflow outlets 3 on the air duct chamber. In areas with high heat load (such as the central region and specific hot spots), the distribution density of the airflow outlets is designed to be higher, for example, 3 outlets per square centimeter, while in areas with low heat load, the density is reduced, for example, 1 outlet per square centimeter. In some examples, the diameter of the air outlets in the hot spot areas can also be appropriately increased (e.g., from 1.0 mm to 1.2 mm).

[0092] Through non-uniform distribution design, on-demand cooling can be achieved, and more initial airflow for cooling can be precisely directed to the parts that need heat dissipation the most. This makes the temperature field of the entire cavity cover surface more uniform and avoids thermal stress problems caused by local hot spots. For example, the maximum temperature difference ΔT can be controlled within ±1.5℃. This breaks through the traditional uniform opening design thinking and significantly improves the uniformity of heat dissipation.

[0093] Example 7: Temperature Control Method in Cooling Scenarios refer to Figure 5 This embodiment illustrates the temperature control method based on the above system as follows: Step S202: Provide initial airflow: Turn on the device and provide a stable initial airflow for cooling using the built-in air cooling system of the RF matching unit 5 or an auxiliary air source. Preferably, the initial airflow required for cooling comes from the heat dissipation airflow of the RF matching unit 5 of the plasma processing device, thus eliminating the need for an additional air source, saving space and cost, and achieving energy saving and integration.

[0094] Step S204, Pure Pneumatic Boosting: The initial airflow is guided into a pure pneumatic airflow booster device 7 (such as an air amplifier), where its internal physical structure (non-electronic or mechanical control) automatically completes processes such as acceleration, entrainment, mixing, and diffusion, thereby accelerating and amplifying the initial airflow to generate a boosted airflow. It should be noted that the core of pure pneumatic boosting is utilizing fluid dynamics principles to achieve energy conversion and amplification, fundamentally avoiding the vibration drawbacks of traditional fan cooling.

[0095] Step S206, Guiding and deflection of the fixed guide surface: The pressurized and amplified airflow is ejected from the airflow outlet 3, and then the pressurized airflow impacts a fixed baffle with a pre-set angle inside the air duct chamber, causing the airflow direction to be forcibly deflected and gain tangential momentum. Therefore, the generation of the flow field does not depend on active control elements, but only on the fixed baffle to achieve guidance and deflection, which has extremely high reliability.

[0096] Step S208: Multi-flow coupling generates a spiral flow field: Multiple deflected airflows in a confined space rely on the momentum exchange and viscosity of the fluids themselves to spontaneously couple and form an ordered three-dimensional spiral airflow field. This enables a self-organizing process from "disordered" or "locally ordered" airflow to achieve "overall order," thereby forming an airflow field with a "tornado effect."

[0097] Step S210, sweeping heat transfer: The combined airflow of the spiral flow field can sweep along the inner surface of the confined space, thereby carrying away the heat of the upper electrode area through strong convection, and the exhaust airflow that completes the heat transfer is discharged from the system through the exhaust vent 1.

[0098] In the above method example, an initial cooling airflow is provided by using existing equipment, and the initial airflow is accelerated and amplified by pure aerodynamic principles to generate a pressurized airflow. After the high-speed pressurized airflow is guided by a fixed guide surface, the airflow direction is deflected to form a spiral airflow. After the spiral airflow is guided to the confined space near the surface to be cooled (such as the inner surface of the upper electrode cavity cover), multiple airflows move and couple in the confined space, spontaneously forming a composite airflow that moves in a three-dimensional spiral motion along the surface to be cooled. Under the continued action of the spiral motion airflow field, the composite airflow forms a "tornado effect", thereby achieving efficient and uniform strong convective heat transfer on the surface to be cooled, and finally being discharged from the exhaust vent.

[0099] Therefore, the above-mentioned cooling control process is based entirely on a passive, pre-set physical structure to generate and control an efficient advanced flow state (spiral flow), achieving automatic and reliable heat dissipation without the need for sensors and complex control algorithms.

[0100] In some examples, the outflow direction of each air outlet can be controlled by setting a fixed tilt angle of the guide surface; furthermore, the rotation axis of the spiral motion airflow field can also be perpendicular to the surface to be cooled, making the cooling effect more uniform.

[0101] Therefore, by presetting the direction of airflow guidance and deflection by fixing the tilt angle, the consistency and repeatability of airflow control can be ensured. Furthermore, by controlling the spatial morphology of the spiral flow field (e.g., setting the rotation axis vertically), the shape of the heat dissipation surface and heat dissipation efficiency are significantly improved.

[0102] Example 8: Plasma Processing Equipment This embodiment describes an ICP etching apparatus that integrates the upper electrode integrated cooling system of the present invention. This plasma processing apparatus is similar to conventional apparatus, including components such as a reaction chamber, an upper electrode, and a lower electrode. However, it differs from conventional apparatus in that it also integrates the upper electrode integrated cooling system described in any of the examples of the present invention. In other words, the upper electrode component of this apparatus integrates the upper electrode integrated cooling system described in any of the examples of the present invention.

[0103] It should be noted that, in addition to the components mentioned above, the ICP etching equipment may also have other components, such as heater 12, sealing components, upper chamber 14, lower chamber 15, etc. Furthermore, this plasma processing equipment can also be used in other applications requiring vibration-free and leak-free cooling and heat dissipation, which will not be listed individually.

[0104] In this specification, the same or similar parts between the various embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the descriptions of the embodiments described later are relatively simple, and relevant parts can be referred to the descriptions of the foregoing embodiments.

[0105] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. An integrated cooling system for the upper electrode of a plasma processing device, characterized in that, include: An air supply unit is used to provide the initial airflow required for cooling; A pure pneumatic airflow booster device (7) has its air inlet connected to the air supply device. The airflow booster device is internally configured to utilize the kinetic energy of the initial airflow to entrain and mix the air in the environment to be cooled, thereby outputting a boosted airflow with a flow rate greater than that of the air inlet. The swirling flow field generating device includes a accommodating chamber (9) and an airflow guiding structure (2) disposed within the accommodating chamber; the inlet of the accommodating chamber (9) is in fluid communication with the outlet of the airflow boosting device (7), and a plurality of airflow outlets (3) are provided on its wall; the airflow guiding structure (2) is configured to guide the incoming boosted airflow, so that multiple airflows discharged from the plurality of airflow outlets (3) interact within a confined space inside the accommodating chamber (9) to form a synthetic airflow with a three-dimensional spiral trajectory, which is used to perform sweeping heat dissipation on the wall of the confined space.

2. The upper electrode integrated cooling system according to claim 1, characterized in that, The airflow guiding structure (2) includes at least one guide surface that is not parallel to the initial flow direction of the pressurized airflow, and the guide surface is configured to give the pressurized airflow a velocity component perpendicular to its initial flow direction.

3. The upper electrode integrated cooling system according to claim 2, characterized in that, The guide surface is a plane or a curved surface, and the angle formed between it and the initial flow direction of the pressurized airflow is in the range of 15° to 60°.

4. The upper electrode integrated cooling system according to claim 3, characterized in that, The included angle is 25° to 35°.

5. The upper electrode integrated cooling system according to any one of claims 1-4, characterized in that, The number of airflow guiding structures (2) is multiple and they are arranged circumferentially around the central axis of the accommodating chamber (9), so that the airflow discharged from the multiple airflow outlets (3) distributed circumferentially generates a resultant torque around the central axis, thereby driving the resultant airflow to rotate. And / or, the gas supply device includes a duct (6) connected to the heat dissipation vent of the radio frequency matching unit (5) of the plasma processing equipment. And / or, the accommodating chamber (9) is integrally formed or fixedly connected to the cavity cover structure of the upper electrode of the plasma processing device, such that the confined space is the space formed by the inner surface of the cavity cover and a covering member; And / or, the accommodating chamber (9) also integrates a process gas distribution function, and its interior is provided with a flow channel that guides the process gas to a spray head (11); And / or, the plurality of airflow outlets (3) are non-uniformly distributed on the wall of the accommodating chamber (9), and their distribution density is set according to the expected heat load distribution of the confined space wall; And / or, the airflow booster (7) includes an air amplifier, the air amplifier including an annular nozzle and a diffuser chamber communicating with the annular nozzle.

6. A temperature control method for a plasma processing device, applied to the upper electrode region of the device, characterized in that, The method includes: Provide an initial airflow required for cooling; The initial airflow is accelerated and its flow rate is amplified to generate a pressurized airflow; By guiding the pressurized airflow through multiple air outlets into a confined space, the pressurized airflow is guided to impact one or more guide surfaces, causing the flow direction of the pressurized airflow to be deflected. Then, multiple airflows couple within the confined space, spontaneously forming a composite airflow with a three-dimensional spiral motion. The combined airflow is used to perform sweeping heat dissipation on the walls of the confined space.

7. The temperature control method according to claim 6, characterized in that, The outflow direction of each air outlet is matched and set according to the fixed tilt angle of the guide surface.

8. The temperature control method according to claim 6, characterized in that, The initial airflow originates from the cooling airflow of the radio frequency matching unit of the plasma processing equipment.

9. A plasma processing device, comprising a reaction chamber and an upper electrode, characterized in that, The upper electrode is integrated with an upper electrode integrated cooling system as described in any one of claims 1 to 5.

10. The plasma processing apparatus according to claim 9, characterized in that, The plasma processing equipment includes an inductively coupled plasma etching device.

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