A reaction chamber and wafer processing apparatus

Abstract

The application relates to the technical field of wafer processing equipment, in particular to a reaction chamber and wafer processing equipment, which comprise a quartz tube, a ceramic top plate, an induction coil, a Faraday shield cage and a radio frequency feeding electrode; the quartz tube is arranged at the top of a processing chamber; the ceramic top plate is arranged at the opening part of the quartz tube to block the quartz tube; the Faraday shield cage is annularly arranged between the quartz tube and the induction coil, a plurality of slits are formed in the Faraday shield cage and extend along the axial direction of the side wall of the Faraday shield cage; the radio frequency feeding electrode is arranged on the ceramic top plate and connected with a radio frequency power supply; the induction coil is annularly arranged outside the quartz tube and connected with an externally arranged radio frequency power supply; the application separates the ignition and maintenance functions, ignites in a safe position far from the side wall of the quartz tube by using a capacitive coupling electric field, and then maintains the plasma by using an optimized inductive coupling mode, so that the high-efficiency plasma processing capacity is ensured, the quartz tube is greatly protected, and the equipment service life and process yield are improved.

Description

Technical Field

[0001] This invention relates to the field of wafer processing equipment technology, and more particularly to a reaction chamber and wafer processing equipment. Background Technology

[0002] In ICP-type plasma resist stripping or etching equipment used in high-hydrogen processes, although the high-frequency electromagnetic field generated by the coil can effectively excite the plasma, the unavoidable capacitive coupling between the coil and the gas in the reaction chamber causes the plasma (especially hydrogen plasma) to bombard the inner wall of the quartz dielectric window, i.e., the quartz tube, resulting in erosion. Although setting a Faraday shield between the coil and the quartz tube can alleviate this problem to some extent, the open area corresponding to the slit of the quartz tube inner wall and the Faraday shield, as well as the intersection of this open area and the coil, will still be subject to concentrated bombardment by hydrogen ions. After long-term use, this will still lead to erosion of the quartz tube and the shedding of particulate matter, which will then contaminate the wafer, affecting the lifespan of the equipment and the process yield. Summary of the Invention

[0003] This invention proposes a reaction chamber and wafer processing equipment. The purpose is to separate the ignition and maintenance functions, use a capacitive coupling electric field to ignite at a safe position away from the sidewall of the quartz tube, and then use an optimized inductive coupling mode to maintain the plasma. This ensures high-efficiency plasma processing capabilities while greatly protecting the quartz tube and improving equipment life and process yield.

[0004] To achieve the above objectives, the present invention provides a reaction chamber comprising a quartz tube, a ceramic top plate, an induction coil, a Faraday shielding cage, and a radio frequency feed electrode;

[0005] The quartz tube is located at the top of the processing chamber;

[0006] The ceramic top plate is disposed at the opening of the quartz tube to seal the quartz tube;

[0007] The Faraday shielding cage is arranged between the quartz tube and the induction coil, and the Faraday shielding cage has a number of slits that penetrate its sidewalls and extend axially.

[0008] The radio frequency feed electrode is disposed on the ceramic top plate and connected to the radio frequency power supply, so as to form a capacitive coupling electric field between the radio frequency feed electrode and the inner bottom wall of the processing chamber after radio frequency energy is introduced, which can ionize the process gas to generate initial plasma and the electric field direction is along the axis.

[0009] The induction coil is arranged around the outside of the quartz tube and connected to the external radio frequency power supply. It is used to generate an alternating magnetic field that can enter the quartz tube through the slit and maintain or increase the concentration of the ionized initial plasma through the alternating magnetic field.

[0010] Optionally, a matching device is connected in the circuit between the radio frequency power supply and the induction coil to adjust the output impedance of the radio frequency power supply to match the load impedance of the plasma.

[0011] A balancing capacitor is connected in the circuit between the induction coil and the ground to provide an RF grounding loop for the induction coil and to balance the voltage across the induction coil, suppressing its common-mode potential to ground.

[0012] Optionally, the input terminal of the RF feed electrode is connected to an adjustable capacitor, which is connected to the circuit node between the balancing capacitor and the induction coil, so that the RF feed electrode obtains the RF energy signal in parallel from the RF circuit of the induction coil, and the signal strength of the RF energy in parallel to the RF feed electrode is adjusted by controlling the capacitance value of the adjustable capacitor.

[0013] Optionally, the input terminal of the RF feed electrode is connected to an adjustable capacitor, which is connected to the circuit node between the RF power supply and the induction coil, so that the RF feed electrode can obtain the RF energy signal in parallel from the path of the RF power supply, and the signal strength of the RF energy in parallel to the RF feed electrode can be adjusted by controlling the capacitance value of the adjustable capacitor.

[0014] Optionally, the radio frequency feed electrode includes any one of several annular structures, several circular structures, and several rectangular structures, and several radio frequency feed electrodes are arranged in a ring structure on the ceramic top plate.

[0015] Alternatively, the radio frequency feed electrode may include a ring-shaped structure, and one of the ring-shaped structures may be coaxially disposed on the ceramic top plate.

[0016] Optionally, the ceramic top plate has several gas distribution channels inside;

[0017] The inlets of several gas distribution channels are connected to the process gas supply system. The gas distribution channels have an arc-shaped structure with the dome facing the direction of the radio frequency feed electrode. The outlets of the gas distribution channels are connected to the inner cavity of the quartz tube and are located directly below the radio frequency feed electrode.

[0018] Optionally, the top of the ceramic top plate is provided with a first recessed portion that is recessed towards the bottom;

[0019] The radio frequency feed electrode is axially movable within the first recess;

[0020] The radio frequency (RF) feed electrode is connected to a drive component of an external device. The drive component drives the RF feed electrode to move axially toward or away from the inner bottom wall of the processing chamber within the first recess, thereby adjusting the intensity of the capacitive coupling electric field between the RF feed electrode and the inner bottom wall of the processing chamber by adjusting the distance between the RF feed electrode and the inner bottom wall of the processing chamber.

[0021] Optionally, the top of the ceramic top plate is provided with a second recessed portion that is recessed towards the bottom;

[0022] The bottom of the radio frequency feed electrode is provided with a protrusion extending toward the inner cavity of the quartz tube. The protrusion is inserted into the second recess so that when the radio frequency feed electrode is energized, the capacitive coupling electric field is concentrated around the protrusion.

[0023] Optionally, the slit has a circumferential width of 1 mm to 30 mm.

[0024] To achieve the above objectives, the present invention also provides a wafer processing apparatus, comprising:

[0025] The aforementioned reaction chamber;

[0026] A process gas supply system, the gas outlet of which is located on a ceramic top plate and communicates with the inner cavity of a quartz tube, so as to supply process gas into the quartz tube.

[0027] A vacuum system, connected to the inner cavity of the quartz tube, is used to extract gas from the quartz tube and maintain the required vacuum level in the quartz tube.

[0028] The radio frequency power supply is electrically connected to the induction coil and the radio frequency feed electrode.

[0029] The beneficial effects of this invention are as follows:

[0030] In this invention, the radio frequency (RF) feed electrode is positioned on the ceramic top plate and connected to the RF power supply. After RF energy is supplied, it forms a capacitively coupled electric field with the inner bottom wall of the processing chamber. This electric field ionizes the process gas to generate initial plasma, thus completing the "ignition" process. Because this initial plasma is excited near the ceramic top plate (rather than the sidewall of the quartz tube), the axial movement of hydrogen ions in the initial stage mainly occurs between the RF feed electrode and the bottom wall of the processing chamber, thereby avoiding direct impact of hydrogen ions on the inner wall of the quartz tube and fundamentally mitigating the high-energy particle bombardment experienced by the quartz tube during this stage. Subsequently, the induction coil surrounding the outside of the quartz tube operates, generating an alternating magnetic field that can penetrate the quartz tube. This magnetic field inductively couples with the ignited initial plasma, thereby maintaining or increasing the plasma concentration to support subsequent wafer processing. Attached Figure Description

[0031] Figure 1 This is a schematic diagram of the structure of the wafer processing equipment in an embodiment of the present invention. Figure 1 ;

[0032] Figure 2 for Figure 1 Schematic diagram of the structure of the quartz tube and Faraday shielding cage;

[0033] Figure 3 This is a schematic diagram of the structure of the wafer processing equipment in an embodiment of the present invention. Figure 2 ;

[0034] Figure 4 This is a schematic diagram of the structure of the radio frequency feed electrode in the reaction chamber according to an embodiment of the present invention. Figure 1 ;

[0035] Figure 5 This is a schematic diagram of the structure of the radio frequency feed electrode in the reaction chamber according to an embodiment of the present invention. Figure 2 ;

[0036] Figure 6 This is a schematic diagram of the structure of the radio frequency feed electrode in the reaction chamber according to an embodiment of the present invention. Figure 3 .

[0037] Explanation of reference numerals in the attached figures:

[0038] 1. Quartz tube; 2. Processing chamber; 3. Induction coil; 4. Faraday shielding cage; 41. Slit; 5. RF feed electrode; 6. Ceramic top plate; 7. RF power supply; 8. Balancing capacitor; 9. Adjustable capacitor; 10. Gas distribution channel; 11. Second recess; 12. Protrusion. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without inventive effort are within the scope of protection of this invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed following the word and its equivalents, but do not exclude other elements or objects.

[0040] To address the problems existing in the prior art, embodiments of the present invention provide a reaction chamber, such as... Figure 1As shown, the reaction chamber includes a quartz tube 1, a ceramic top plate 6, an induction coil 3, a Faraday shielding cage 4, and a radio frequency feed electrode 5.

[0041] In one embodiment, such as Figure 1 As shown, the quartz tube 1 is located at the top of the processing chamber 2.

[0042] In one embodiment, such as Figure 1 As shown, the ceramic top plate 6 is disposed at the opening of the quartz tube 1 to seal the quartz tube 1.

[0043] In one embodiment, such as Figure 1 and Figure 2 As shown, the Faraday shielding cage 4 is arranged in a ring between the quartz tube 1 and the induction coil 3, and the Faraday shielding cage 4 has a number of slits 41 that penetrate its sidewalls and extend axially.

[0044] In one embodiment, such as Figure 1 As shown, the radio frequency (RF) feed electrode 5 is disposed on the ceramic top plate 6 and connected to the RF power supply 7. This allows for the formation of a capacitively coupled electric field between the RF feed electrode 5 and the inner bottom wall of the processing chamber 2 after RF energy is applied. This field ionizes the process gas to generate initial plasma, and its direction is axial. This embodiment creates an independent and controllable plasma "ignition" source by applying RF energy between the RF feed electrode 5 and the inner bottom wall of the processing chamber 2, forming a strong capacitively coupled electric field along the axial direction. This effectively isolates the initial plasma generation location from the side wall of the quartz tube 1. The RF feed electrode 5 is disposed on the ceramic top plate 6, forming a capacitor with the inner bottom wall of the processing chamber 2 below. When RF energy is applied, a strong capacitively coupled electric field with an axial direction is formed between them (including the cavity enclosed by the processing chamber 2 and the quartz tube 1). The process gas (such as hydrogen) is efficiently ionized within this electric field region, thereby generating initial plasma. This "ignition" process is precisely confined to the top center region of the reaction chamber (i.e., below the radio frequency feed electrode 5). This ensures that, during the crucial initial stage of plasma generation, the axial acceleration and movement of high-energy charged particles (especially hydrogen ions) primarily occur between the radio frequency feed electrode 5 and the inner bottom wall of the processing chamber 2, preventing radial movement towards the inner wall of the quartz tube. This fundamentally prevents high-energy particles from moving towards the sidewall of the quartz tube 1 in the initial stage, effectively reducing the direct impact and bombardment of hydrogen ions on the inner wall of the quartz tube 1 and mitigating the erosion problem of the quartz tube 1 during the plasma ignition stage.

[0045] In one embodiment, such as Figure 1As shown, the induction coil 3 is arranged around the outside of the quartz tube 1 and connected to the external radio frequency power supply 7. It generates an alternating magnetic field that can enter the quartz tube 1 through the slit 41, and uses this alternating magnetic field to maintain or increase the concentration of the ionized initial plasma. This arrangement allows the induction coil 3 and the radio frequency feed electrode 5 to perform their respective functions, effectively decoupling the plasma generation and maintenance functions, thereby optimizing plasma characteristics and protecting the core components of the equipment. The induction coil 3 is arranged around the quartz tube 1, and the alternating magnetic field it generates can penetrate the slit 41 of the quartz tube 1 and the Faraday shield 4, entering the reaction chamber. The main target of this magnetic field is the initial plasma ignited by the capacitive coupling electric field of the radio frequency feed electrode 5. Through the inductive coupling mechanism, the alternating magnetic field induces a vortex electric field in the initial plasma, efficiently ohmically heating the electrons in the plasma, thereby continuously replenishing the plasma energy, maintaining its concentration, and even further increasing the plasma density as needed during the processing. Since the energy of the induction coil 3 is mainly transferred to the plasma through the magnetic field (inductive coupling) rather than the electric field (capacitive coupling), and the Faraday shielding cage 4 significantly weakens the harmful capacitive coupling between the induction coil 3 and the plasma, the plasma potential is reduced. This not only improves the uniformity and controllability of the plasma density, but more importantly, it greatly reduces the directional bombardment and sputtering erosion of the sidewall of the quartz tube 1 by high-energy ions (especially hydrogen ions), solves the problem of damage to the quartz tube 1 and particulate matter contamination, and improves the stability of the process and the service life of the equipment.

[0046] The axial, radial, and circumferential directions described in this invention coincide with or are parallel to the axial, radial, and circumferential directions of the quartz tube 1, and will not be explained further below.

[0047] In one embodiment, such as Figure 1As shown, a matching device is connected in the circuit between the RF power supply 7 and the induction coil 3 to adjust the output impedance of the RF power supply 7 to match the load impedance of the plasma. A balancing capacitor 8 is connected in the circuit between the induction coil 3 and ground to provide an RF grounding loop for the induction coil 3 and to balance the voltage across the induction coil 3, suppressing its common-mode potential to ground. In this embodiment, the matching device and balancing capacitor 8 optimize the transmission efficiency and system stability of RF energy from two key aspects: impedance matching and electrical balance, thereby ensuring the controllable and efficient operation of the plasma process. Specifically, in principle, the matching device is set between the RF power supply 7 and the induction coil 3. Its function is to dynamically adjust the output impedance of the RF power supply 7 to achieve conjugate matching with the impedance of the plasma load (whose impedance fluctuates with process conditions). This minimizes the reflection loss of RF energy in the transmission path, ensures maximum energy transmission efficiency from the power supply to the plasma, and provides a solid power foundation for the induction coil 3 to generate a stable and sufficient alternating magnetic field to maintain the plasma. Meanwhile, the balancing capacitor 8 placed between the induction coil 3 and the ground serves a dual purpose: firstly, it provides a low-impedance radio frequency grounding loop for the induction coil 3, which helps stabilize the radio frequency potential of the induction coil 3; secondly, through the capacitive voltage division effect of the capacitor, it balances the voltage to ground across the induction coil 3, suppressing the common-mode potential of the induction coil 3 relative to ground. This design effectively reduces the harmful capacitive coupling component between the induction coil 3 and the plasma caused by the potential difference, further reducing the bombardment of dielectric windows such as the quartz tube 1 by high-energy ions, improving the uniformity of the plasma, and protecting the reaction chamber.

[0048] In one embodiment, such as Figure 1As shown, an adjustable capacitor 9 is connected to the input terminal of the RF feed electrode 5. The adjustable capacitor 9 is connected to the circuit node between the balancing capacitor 8 and the induction coil 3, allowing the RF feed electrode 5 to obtain RF energy signals in parallel from the RF circuit of the induction coil 3. The signal strength of the RF energy parallel to the RF feed electrode 5 is adjusted by controlling the capacitance of the adjustable capacitor 9. This embodiment provides a "passive" but controllable ignition auxiliary circuit by setting the adjustable capacitor 9, enabling the RF feed electrode 5 to obtain RF energy signals in parallel from the RF main circuit of the induction coil 3. The advantage is that by adjusting the capacitance of the adjustable capacitor 9, the voltage amplitude (i.e., signal strength) of the RF signal parallel to the RF feed electrode 5 can be precisely controlled, thus providing a precisely regulated source of excitation energy for the RF feed electrode 5 and achieving fine control of the plasma ignition process. This allows the operator to flexibly adjust the strength of the capacitive coupling electric field generated by the RF feed electrode 5 without changing the output power of the RF power supply 7. This allows for the optimization of initial plasma ignition conditions (such as lowering the voltage threshold required for ignition) and control of the initial plasma density and spatial distribution. This indirect parallel and independent adjustment mechanism ensures stable ignition while decoupling and independently optimizing the ignition process from the coil sustaining process, thereby improving the window width and controllability of the entire plasma processing technology.

[0049] In one embodiment, such as Figure 3As shown, the input terminal of the RF feed electrode 5 is connected to an adjustable capacitor 9. The adjustable capacitor 9 is connected to the circuit node between the RF power supply 7 and the induction coil 3, so that the RF feed electrode 5 obtains RF energy signals in parallel from the path of the RF power supply 7, and the signal strength of the RF energy in parallel to the RF feed electrode 5 is adjusted by controlling the capacitance value of the adjustable capacitor 9. This provides the RF feed electrode 5 with an ignition control design that is relatively isolated from the circuit of the induction coil 3 and directly obtains energy in parallel from the main path of the RF power supply 7, thereby achieving decoupling and independent adjustment of the ignition energy and the working state of the main coil circuit. In this embodiment, by connecting the adjustable capacitor 9 to the circuit node between the RF power supply 7 and the induction coil 3, the RF feed electrode 5 directly obtains RF energy signals in parallel from the output path of the RF power supply 7. The advantage of this design is that the strength and characteristics of the parallel RF energy signal mainly depend on the direct output of the RF power supply 7 and the adjustment of the adjustable capacitor 9, and are relatively less affected by the impedance changes of the load (plasma) at the back end of the induction coil 3 circuit. This allows the operator to more directly and stably control the signal strength of the RF feed electrode 5 by adjusting the capacitance of the adjustable capacitor 9, thereby precisely adjusting the strength of the capacitive coupling electric field it generates. This coupling method, which extracts energy from the source (power path), ensures high reliability and repeatability of the plasma "ignition" process. Furthermore, the main discharge process of maintaining the plasma with the induction coil 3 can be independently optimized. Even when the matching state of the induction coil 3 or the plasma load changes, the ignition conditions remain relatively stable, improving the overall start-up success rate and controllability of the process.

[0050] In one embodiment, the radio frequency feed electrode 5 includes several annular structures and several circular structures (such as...). Figure 5 (as shown) and several rectangular structures (such as) Figure 6 Any one of the following (as shown), and a plurality of the radio frequency feed electrodes 5 are arranged in a ring structure on the ceramic top plate 6. This embodiment provides the possibility of flexible design and optimization of the plasma ignition electric field by offering a variety of choices for the shape and arrangement of the radio frequency feed electrodes 5, to adapt to different reaction chamber sizes, process gas types and process objectives; or the radio frequency feed electrode 5 includes a ring structure (such as...). Figure 4As shown in the diagram, a ring-shaped structure is coaxially disposed on the ceramic top plate 6. Specifically, setting a ring-shaped radio frequency (RF) feed electrode 5 can generate a ring-shaped strong electric field region around the central axis of the RF feed electrode 5, which is beneficial for concentrating plasma ignition at a specific radial position; several circular RF feed electrodes 5 can generate a more concentrated central electric field, suitable for powerful ignition in the central region of the reaction chamber; while several rectangular structures can form a directional electric field in a specific direction. More importantly, several RF feed electrodes 5 can be set and arranged in a ring structure to form a multi-point, ring-shaped distribution design, so that the RF feed electrodes 5 can cover a larger area on the ceramic top plate 6, thereby generating a more uniformly distributed capacitive coupling electric field in a larger radial range. This helps to avoid uneven initial plasma density caused by overly concentrated ignition positions, making the transition from "ignition" to "maintenance" of the induction coil 3 smoother, ultimately improving the uniformity of the entire plasma in the processing area and improving the overall effect of plasma processing.

[0051] Of course, in other embodiments, the shapes of several radio frequency feed electrodes 5 can be used simultaneously and interchangeably. This can combine the electric field characteristics generated by different electrode shapes, and achieve customization and optimization of the plasma ignition electric field in three-dimensional space (especially in the radial and circumferential directions). For example, both annular and circular radio frequency feed electrodes 5 can be arranged on the ceramic top plate 6. Specifically, in one embodiment, the interlaced annular and circular structures are combined to form a ring; in another embodiment, the annular and circular structures each form a ring, and these two rings are arranged in a concentric manner. This allows the strong ignition in the central region (provided by the circular electrode) to be combined with the annular uniform ignition in the outer region (provided by the annular electrode), thereby forming an initial plasma with controllable radial gradient and better distribution during the ignition stage. If a rectangular radio frequency feed electrode 5 is combined, the electric field direction can also be finely adjusted. This cross-application approach greatly enhances design flexibility, allowing engineers to "piece together" the most ideal ignition electric field distribution based on the geometry of a specific process chamber, gas flow patterns, and the desired plasma uniformity requirements. This enables plasma ignition effects that are more uniform, more efficient, or have specific spatial distribution characteristics than a single RF feed electrode shape or simple arrangement in complex applications, providing semiconductor processes with a higher process window and greater adjustability.

[0052] In one embodiment, such as Figure 1As shown, the ceramic top plate 6 has several gas distribution channels 10 inside; the inlets of the gas distribution channels 10 are connected to the process gas supply system. The gas distribution channels 10 have an arc-shaped structure, with the dome facing the direction of the radio frequency feed electrode 5. The outlets of the gas distribution channels 10 are connected to the inner cavity of the quartz tube 1 and are located directly below the radio frequency feed electrode 5. This embodiment optimizes the release path and spatial distribution of the process gas in the core region of plasma ignition, thereby improving the ignition efficiency, uniformity, and controllability of the initial plasma. Specifically, the gas distribution channels 10 are built into the ceramic top plate 6, and their outlets are precisely located directly below the radio frequency feed electrode 5. This allows the process gas to be directly delivered to the core region of the capacitively coupled electric field formed by the radio frequency feed electrode 5 and the bottom wall of the processing chamber 2. The gas distribution channel 10 is designed as an arc-shaped structure with its dome facing the radio frequency feed electrode 5. This arc-shaped flow channel guides the process gas to better "wrap" or cover the electric field concentration area below the electrode when it leaves the outlet. This ensures that the process gas molecules have the highest concentration and residence time in the area with the strongest electric field and the easiest to be ionized, which greatly enhances the gas ionization efficiency and reduces the plasma ignition threshold. On the other hand, multiple such channels are evenly distributed below the electrode, which helps to form a more spatially uniform gas environment in the ignition area, laying the foundation for generating a uniform initial plasma and thus improving the overall uniformity of the steady-state plasma maintained by the induction coil 3.

[0053] In one embodiment, the top of the ceramic top plate 6 is provided with a first recessed portion that slopes downwards; the radio frequency (RF) feed electrode 5 is axially movably disposed within the first recessed portion; the RF feed electrode 5 is connected to an external driving component, which drives the RF feed electrode 5 to move axially towards or away from the inner bottom wall of the processing chamber 2 within the first recessed portion, thereby adjusting the strength of the capacitive coupling electric field between the RF feed electrode 5 and the inner bottom wall of the processing chamber 2 by adjusting the distance between the RF feed electrode 5 and the inner bottom wall of the processing chamber 2. By controlling the axial movement of the RF feed electrode 5 within the first recessed portion of the ceramic top plate 6 through the external driving component, the physical distance between the RF feed electrode 5 and the inner bottom wall of the processing chamber 2 can be directly and precisely adjusted, specifically the physical distance between the bottom of the RF feed electrode 5 and the inner bottom wall of the processing chamber 2. This distance is a key parameter determining the field strength and spatial distribution of the capacitive coupling electric field formed between the two. When the RF feed electrode 5 moves downwards closer to the bottom wall of the processing chamber 2, the distance between the capacitor plates formed by the RF feed electrode 5 and the bottom of the processing chamber 2 decreases. Under the same RF voltage, the electric field strength increases, which is beneficial for igniting the plasma under lower power or gas pressure conditions, or for generating a higher density initial plasma. Conversely, when the RF feed electrode 5 moves upwards away from the bottom wall of the processing chamber 2, the distance between the capacitor plates formed by the RF feed electrode 5 and the bottom of the processing chamber 2 increases, and the electric field weakens. This allows for milder ignition conditions or different process formulations. This adjustable design allows operators to flexibly optimize ignition conditions for different process gases, pressures, target plasma densities, and other variables, broadening the process window and improving the compatibility and stability of the equipment in handling different processes.

[0054] In one embodiment, the driving component can be a linear motor, a servo motor, a cylinder, or a combination of a stepper motor and a lead screw / ball screw. Through the external driving component, the RF feed electrode 5 can be automatically and precisely driven to move up and down along its axial direction (i.e., the depth direction of the first recess), thereby achieving dynamic adjustment of its position.

[0055] In one embodiment, such as Figure 3As shown, the top of the ceramic top plate 6 is provided with a second recessed portion 11 that is recessed towards the bottom; the bottom of the RF feed electrode 5 is provided with a protrusion 12 extending towards the inner cavity of the quartz tube 1. The protrusion 12 is inserted into the second recessed portion 11 so that when the RF feed electrode 5 is energized, the capacitive coupling electric field is concentrated around the protrusion 12. This changes the local electric field distribution of the RF feed electrode 5, thereby enhancing the ignition efficiency of the initial plasma. Specifically, a second recessed portion 11 is provided in the ceramic top plate 6, and a protrusion 12 extending into and inserted into the second recessed portion 11 is provided at the bottom of the RF feed electrode 5. When the RF feed electrode 5 is energized, this protrusion 12 extending into the second recessed portion 11 (similar to a "sharp point" or "probe") makes the electric field lines on the surface of the RF feed electrode 5 highly concentrated and dense in this area (i.e., around the protrusion 12). This electric field concentration effect greatly enhances the electric field strength in the local space near the protrusion 12. Since the process gas (through the gas distribution channel 10) is released directly below the RF feed electrode 5, the strong electric field region and the high-concentration gas region can overlap more efficiently, thereby ionizing gas molecules at lower power or in a shorter time, greatly reducing the plasma ignition threshold and improving ignition speed and reliability.

[0056] In one embodiment, the protrusion 12 can be a conical, cylindrical, pyramidal, hemispherical, or any geometric shape with a pointed tip. By designing protrusions 12 of different shapes, the electric field concentration effect near their tips or surfaces can be flexibly controlled. For example, a conical structure or a pyramidal protrusion with a pointed tip can generate a very strong electric field tip effect, achieving extremely high electric field strength in a very small area, thus efficiently igniting the gas even under low power conditions; while a cylindrical or hemispherical protrusion can provide a relatively smoother and wider-covering electric field concentration area, which helps to generate a more uniform initial plasma. This design flexibility allows engineers to select and optimize the geometry of the protrusion 12 according to specific process requirements (such as ignition speed, electric field concentration, plasma uniformity, etc.), thereby achieving fine-grained control of the plasma ignition process.

[0057] In one embodiment, the circumferential width of the slit 41 is 1mm-30mm. This setting allows for a precise balance and optimization of plasma excitation efficiency and protection of the quartz tube 1. On one hand, a sufficiently wide slit 41 (e.g., close to 30mm) allows the alternating magnetic field generated by the induction coil 3 to pass through more effectively, ensuring that the magnetic field strength entering the reaction chamber is sufficient to efficiently inductively couple heating and maintain the plasma, guaranteeing the high plasma density required for the process. On the other hand, controlling the width of the slit 41 within a certain range (e.g., as narrow as 1mm) can significantly limit and weaken the harmful capacitive coupling component between the induction coil 3 and the plasma. By physically limiting the radial penetration of the electric field through the Faraday cage 4, this width range can effectively reduce the plasma potential, thereby greatly reducing the directional bombardment and erosion of the inner wall of the quartz tube 1 by high-energy ions (especially hydrogen ions), solving the core problem of particulate contamination caused by the erosion of the quartz tube 1. Therefore, the range of 1mm to 30mm is a key design parameter that has been carefully weighed, ensuring efficient plasma generation and maintenance while maximizing protection of the core component of the reaction chamber, the quartz tube 1.

[0058] In one embodiment, the Faraday shield 4 is also grounded, thus creating a high-low potential between the RF feed electrode 5 and the Faraday shield 4. The Faraday shield 4, being grounded, is at a low potential, while the RF feed electrode 5 is at a high potential when energized. During ignition, the accelerated free ions tilt towards the RF feed electrode 5, bombarding the inner wall of the quartz tube 1. Although this bombardment is relatively weak, to address this issue, in one embodiment, such as... Figure 1 As shown, the upper part of the quartz tube 1 (i.e. the part connected to the ceramic top plate 6) is made of ceramic material. In this way, even if accelerated ions bombard this area, the more corrosion-resistant ceramic material can effectively resist them, further protecting the equipment from damage and preventing particulate matter contamination.

[0059] In one embodiment, the ceramic top plate 6 and the upper part of the ceramic quartz tube 1 can be integrally molded. This integrated structural design eliminates the physical seam between the two components, which not only fundamentally eliminates the risk of leakage or abnormal discharge caused by plasma at the interface, but also significantly enhances the overall mechanical strength and thermal shock resistance of this critical area. Simultaneously, it avoids interface defects and thermal expansion coefficient mismatches introduced by using different materials or connection processes, thereby improving the long-term reliability and stability of the component in high-temperature, high-vacuum, and plasma environments, further ensuring the cleanliness and service life of the process chamber.

[0060] To address the problems existing in the prior art, embodiments of the present invention also provide a wafer processing apparatus, such as... Figure 1As shown, the wafer processing equipment includes the reaction chamber, process gas supply system, vacuum system, and radio frequency power supply 7; the outlet of the process gas supply system is located on the ceramic top plate 6 and communicates with the inner cavity of the quartz tube 1 to supply process gas to the quartz tube 1; the vacuum system is connected to the quartz tube 1 and is used to extract the gas in the quartz tube 1 and maintain the required vacuum level of the quartz tube 1; the radio frequency power supply 7 is electrically connected to the induction coil 3 and the radio frequency feed electrode 5.

[0061] In one embodiment, the wafer processing equipment can be a plasma etching apparatus, a plasma-enhanced chemical vapor deposition apparatus, or a plasma resist stripping apparatus. Specifically, in the etching apparatus, this design provides stable and uniform plasma for precise material removal; in the deposition apparatus, a controllable plasma environment helps achieve high-quality, uniform film growth; and in the resist stripping apparatus (especially for high-hydrogen processes), it effectively excites plasma while significantly reducing the bombardment and erosion of the quartz window by hydrogen ions.

[0062] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the present invention. Furthermore, the present invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A reaction chamber, characterized in that, Includes a quartz tube, a ceramic top plate, an induction coil, a Faraday shield, and an RF feed electrode; The quartz tube is located at the top of the processing chamber; The ceramic top plate is disposed at the opening of the quartz tube to seal the quartz tube; The Faraday shielding cage is arranged between the quartz tube and the induction coil, and the Faraday shielding cage has a number of slits that penetrate its sidewalls and extend axially. The radio frequency feed electrode is disposed on the ceramic top plate and connected to the radio frequency power supply, so as to form a capacitive coupling electric field between the radio frequency feed electrode and the inner bottom wall of the processing chamber after radio frequency energy is introduced, which can ionize the process gas to generate initial plasma and the electric field direction is along the axis. The induction coil is arranged around the outside of the quartz tube and connected to the external radio frequency power supply. It is used to generate an alternating magnetic field that can enter the quartz tube through the slit and maintain or increase the concentration of the ionized initial plasma through the alternating magnetic field. The top of the ceramic top plate is provided with a second recessed portion that is recessed towards the bottom; The bottom of the radio frequency feed electrode is provided with a protrusion extending toward the inner cavity of the quartz tube. The protrusion is inserted into the second recess so that when the radio frequency feed electrode is energized, the capacitive coupling electric field is concentrated around the protrusion.

2. The reaction chamber according to claim 1, characterized in that, A matching device is connected in the circuit between the radio frequency power supply and the induction coil to adjust the output impedance of the radio frequency power supply to match the load impedance of the plasma. A balancing capacitor is connected in the circuit between the induction coil and the ground to provide an RF grounding loop for the induction coil and to balance the voltage across the induction coil, suppressing its common-mode potential to ground.

3. The reaction chamber according to claim 2, characterized in that, The input terminal of the RF feed electrode is connected to an adjustable capacitor, which is connected to the circuit node between the balancing capacitor and the induction coil, so that the RF feed electrode can obtain the RF energy signal in parallel from the RF circuit of the induction coil, and the signal strength of the RF energy in parallel to the RF feed electrode can be adjusted by controlling the capacitance value of the adjustable capacitor.

4. The reaction chamber according to claim 2, characterized in that, The input terminal of the RF feed electrode is connected to an adjustable capacitor, which is connected to the circuit node between the RF power supply and the induction coil, so that the RF feed electrode can obtain the RF energy signal in parallel from the RF power supply path, and the signal strength of the RF energy in parallel to the RF feed electrode can be adjusted by controlling the capacitance value of the adjustable capacitor.

5. The reaction chamber according to claim 1, characterized in that, The radio frequency feed electrode includes any one of several annular structures, several circular structures, and several rectangular structures, and several radio frequency feed electrodes are arranged in a ring structure on the ceramic top plate. Alternatively, the radio frequency feed electrode may include a ring-shaped structure, and one of the ring-shaped structures may be coaxially disposed on the ceramic top plate.

6. The reaction chamber according to claim 1, characterized in that, The ceramic top plate has several gas distribution channels inside; The inlets of several gas distribution channels are connected to the process gas supply system. The gas distribution channels have an arc-shaped structure with the dome facing the direction of the radio frequency feed electrode. The outlets of the gas distribution channels are connected to the inner cavity of the quartz tube and are located directly below the radio frequency feed electrode.

7. The reaction chamber according to claim 1, characterized in that, The top of the ceramic top plate is provided with a first recessed portion that is recessed towards the bottom; The radio frequency feed electrode is axially movable within the first recess; The radio frequency (RF) feed electrode is connected to a drive component of an external device. The drive component drives the RF feed electrode to move axially toward or away from the inner bottom wall of the processing chamber within the first recess, thereby adjusting the intensity of the capacitive coupling electric field between the RF feed electrode and the inner bottom wall of the processing chamber by adjusting the distance between the RF feed electrode and the inner bottom wall of the processing chamber.

8. The reaction chamber according to claim 1, characterized in that, The slit has a circumferential width of 1 mm to 30 mm.

9. A wafer processing apparatus, characterized in that, include: The reaction chamber as described in any one of claims 1 to 8; A process gas supply system, the gas outlet of which is located on a ceramic top plate and communicates with the inner cavity of a quartz tube, so as to supply process gas into the quartz tube. A vacuum system, connected to the inner cavity of the quartz tube, is used to extract gas from the quartz tube and maintain the required vacuum level in the quartz tube. The radio frequency power supply is electrically connected to the induction coil and the radio frequency feed electrode.

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