A reaction chamber for plasma processing and a semiconductor processing apparatus

Abstract

The application relates to the technical field of wafer processing equipment, in particular to a reaction chamber for plasma processing and a semiconductor processing equipment, which comprises a dielectric window, an induction coil and a movable shield; the dielectric window is arranged at the top of a processing chamber; the induction coil is arranged around the outside of the dielectric window; the movable shield is arranged around the dielectric window and the induction coil and can move up and down along the axial direction of the dielectric window or perform telescopic movement; during the plasma ignition stage, the movable shield moves to a position staggered with the induction coil; after the plasma ignition is completed, the movable shield is reset between the dielectric window and the induction coil; the movable shield is arranged to avoid the problem that the magnetic field is shielded during ignition, and can effectively block the bombardment of high-energy ions on the dielectric window in the steady-state process, so that the erosion of the dielectric window and the generation of particles are reduced, and the service life of the equipment and the 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 semiconductor processing equipment for plasma processing. 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 induction coil can effectively excite the plasma, the unavoidable capacitive coupling between the induction coil and the gas in the reaction chamber causes the plasma (especially hydrogen plasma) to bombard the quartz dielectric window, resulting in erosion. Although setting a Faraday shield between the induction coil and the dielectric window can alleviate this problem to some extent, the intersection of the slit opening area and the induction coil will still be subject to concentrated bombardment by hydrogen ions. After long-term use, this will still lead to erosion of the dielectric window and the shedding of particulate matter, which will then contaminate the wafer, affecting the equipment life and process yield. Summary of the Invention

[0003] This invention proposes a reaction chamber and semiconductor processing equipment for plasma processing. The purpose is to avoid the problem of magnetic field shielding during ignition by setting up a movable shielding component, and to effectively block the bombardment of dielectric windows by high-energy ions in steady-state processes, thereby reducing the corrosion of dielectric windows and the generation of particulate matter, and improving equipment life and process yield.

[0004] To achieve the above objectives, the present invention provides a reaction chamber for plasma processing, comprising a dielectric window, an induction coil, and a movable shield:

[0005] The medium window is located at the top of the processing chamber;

[0006] The induction coil is arranged around the outside of the dielectric window and connected to the external radio frequency power supply. It is used to generate an alternating magnetic field that can enter the dielectric window so as to induce an eddy current electric field through the alternating magnetic field to accelerate the collision of free electrons with the process gas to generate plasma.

[0007] The movable shield is arranged around the medium window and the induction coil, and can move up and down or extend and retract along the axial direction of the medium window.

[0008] During the plasma ignition stage, the movable shield moves to a position where its orthographic projection structure on the dielectric window is offset from the orthographic projection structure of the induction coil on the dielectric window, so that the alternating magnetic field generated by the induction coil can penetrate into the dielectric window. After plasma ignition is completed, the movable shield returns to a position between the dielectric window and the induction coil, and its orthographic projection structure on the dielectric window covers the orthographic projection structure of the induction coil on the dielectric window, so as to shield and protect the dielectric window.

[0009] Optionally, the movable shielding component includes a plurality of annular shielding portions arranged sequentially along the axial direction, and the annular shielding portion near the processing chamber is connected to the top of the processing chamber; any two adjacent annular shielding portions include a first annular shielding portion and a second annular shielding portion, the mating end of the first annular shielding portion is provided with a receiving groove extending along the axial direction, and at least a portion of the second annular shielding portion is slidably inserted into the receiving groove, and can move toward or away from the bottom of the receiving groove, so as to reduce or increase the overall height of the movable shielding component in the axial direction.

[0010] Optionally, the receiving groove has an axially extending anti-detachment groove on the side wall near the opening end, and the second annular shield has an anti-detachment block on the side wall near its insertion end. The anti-detachment block is slidably disposed in the anti-detachment groove to prevent the second annular shield from detaching from the receiving groove.

[0011] Optionally, the annular shield that is furthest from the top of the processing chamber among the plurality of annular shields is the third annular shield. The third annular shield is connected to an axial drive member, which drives the third annular shield to move axially toward or away from the bottom of the receiving groove of the annular shield below it. The driving force is transmitted sequentially through the nested sliding fit between the annular shields, so that the annular shield in the upper position slides in the receiving groove of the annular shield in the lower position, thereby reducing or increasing the overall height of the movable shield in the axial direction.

[0012] Optionally, the reaction chamber for plasma treatment further includes a first sensor and a first processor. The first processor is connected to the axial drive and the first sensor respectively. The first sensor is disposed inside or outside the medium window to collect the plasma concentration inside the medium window. According to the ignition command signal, the first processor controls the axial drive to drive the movable shield to extend and retract along the axial direction of the medium window. After the plasma concentration is greater than or equal to a preset threshold, the processor controls the axial drive to drive the movable shield to reset between the medium window and the induction coil to shield and protect the medium window.

[0013] Optionally, the first annular shield is provided with a first slit extending circumferentially, and the second annular shield is provided with a second slit extending axially. A plurality of the first and second slits are provided and arranged axially. When the movable shield is reset between the dielectric window and the induction coil, the first and second slits located in the overlapping area of ​​the first and second annular shields overlap to form a first channel for the alternating magnetic field to enter the dielectric window. The first and second slits located in the non-overlapping area of ​​the first and second annular shields independently form a second channel for the alternating magnetic field to enter the dielectric window.

[0014] Optionally, both the first slit and the second slit include a plurality of sub-slits spaced apart circumferentially;

[0015] The induction coil includes several annular segments arranged at intervals along the axial direction, and a connecting segment connecting two adjacent annular segments. When the movable shield is reset between the dielectric window and the induction coil, the orthographic projection structure of the sub-slits on the dielectric window is located between the orthographic projection structures of two adjacent annular segments on the dielectric window, and the orthographic projection structure of the connecting segment on the dielectric window is located between the orthographic projection structures of two circumferentially adjacent sub-slits on the dielectric window.

[0016] Optionally, the movable shielding component includes a pneumatic telescopic shielding tube and an air-filling / exhausting component; the pneumatic telescopic shielding tube is located at the top of the processing chamber, and an air storage cavity is provided inside its tube wall; the air-filling / exhausting component is connected to the air storage cavity, so as to fill the air storage cavity with air through the air-filling / exhausting component, thereby causing the pneumatic telescopic shielding tube to perform telescopic movement.

[0017] Optionally, the active shielding component further includes a second sensor and a second processor, the second processor being connected to the gas pumping component and the second sensor, and the second sensor being disposed within the medium window to collect the plasma concentration within the medium window;

[0018] The second processor controls the pumping and filling device to draw air from the gas storage chamber of the pneumatic telescopic shield tube according to the ignition command signal, causing the pneumatic telescopic shield tube to contract. After the contraction, the orthographic projection structure of the pneumatic telescopic shield tube on the medium window is offset from the orthographic projection structure of the induction coil on the medium window. After receiving that the plasma concentration is greater than or equal to a preset threshold, the processor controls the pumping and filling device to fill the gas storage chamber of the pneumatic telescopic shield tube, so that the pneumatic telescopic shield tube returns to the position between the medium window and the induction coil, thereby shielding and protecting the medium window.

[0019] Optionally, the induction coil includes several annular segments arranged at intervals along the axial direction, and a connecting segment connecting two adjacent annular segments. The pneumatic telescopic shielding tube is provided with several circumferentially extending third slits to form a third channel for the alternating magnetic field to enter the dielectric window. The third slits are located between two adjacent annular segments, and the orthographic projection structure of the third slits on the dielectric window is offset from the orthographic projection structure of the connecting segment on the dielectric window.

[0020] Optionally, the movable shielding component further includes several guide components. The several guide components are arranged in a ring at equal intervals on the top of the processing chamber and extend axially. The wall of the pneumatic telescopic shielding tube is provided with several guide holes that are axially connected. The guide holes are not connected to the air storage chamber. The guide components are movably disposed in the guide holes one by one to guide the pneumatic telescopic shielding tube when it performs axial telescopic movement.

[0021] To achieve the above objectives, the present invention also provides a semiconductor processing apparatus, comprising:

[0022] The aforementioned reaction chamber for plasma processing;

[0023] A process gas supply system is connected to a medium window to supply process gas into the medium window;

[0024] A vacuum system, connected to the medium window, is used to extract gas from the medium window and maintain the required vacuum level of the medium window;

[0025] The radio frequency power supply is electrically connected to the induction coil.

[0026] The beneficial effects of this invention are as follows:

[0027] This invention introduces a movable shield that can move up and down or extend and retract along the axial direction. During the plasma ignition phase, this shield is moved so that its projection structure on the dielectric window is misaligned with the projection structure of the induction coil, allowing the alternating magnetic field to penetrate the dielectric window unimpeded for efficient ignition. After plasma ignition, the movable shield is reset to between the dielectric window and the induction coil, completely covering the coil's projection structure, thus providing shielding protection for the dielectric window during the process. This dynamic shielding mechanism fundamentally avoids the problem of magnetic field shielding during ignition and effectively blocks high-energy ion bombardment of the dielectric window during steady-state processes, significantly reducing dielectric window erosion and particulate matter generation, thereby improving equipment lifespan and process yield. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the structure of the semiconductor processing device in an embodiment of the present invention;

[0029] Figure 2 for Figure 1 An enlarged schematic diagram of the structure at position A in the illustrated embodiment;

[0030] Figure 3 for Figure 1 A partial structural schematic diagram of the overlapping area of ​​two adjacent annular shielding parts in the embodiment shown.

[0031] Figure 4 This is a schematic diagram of the structure of the pneumatic telescopic shielding tube and the air-filling component in an embodiment of the present invention;

[0032] Figure 5 for Figure 4 The schematic diagram of the pneumatic telescopic shielding tube in the embodiment shown is a top view.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Medium window; 2. Induction coil; 3. Movable shield; 31. Annular shield; 32. Receiving groove; 33. First slit; 34. Second slit; 4. Processing chamber; 5. Anti-detachment groove; 6. Anti-detachment block; 7. Axial drive component; 8. Drive end; 9. Pneumatic telescopic shield tube; 10. Air pumping component; 11. Guide component. Detailed Implementation

[0035] 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.

[0036] To address the problems existing in the prior art, embodiments of the present invention provide a reaction chamber for plasma processing. By setting up a movable shielding component, the problem of magnetic field shielding during ignition is avoided, and high-energy ions can be effectively blocked from bombarding the dielectric window in steady-state processes, reducing the erosion of the dielectric window and the generation of particulate matter, thereby improving equipment life and process yield.

[0037] In one embodiment, such as Figure 1 As shown, the reaction chamber for plasma processing includes a dielectric window 1, an induction coil 2, and a movable shield 3.

[0038] In one embodiment, such as Figure 1 As shown, the medium window 1 is located at the top of the processing chamber 4.

[0039] In one embodiment, such as Figure 1 As shown, the induction coil 2 is arranged around the outside of the dielectric window 1 and connected to the external radio frequency power supply. It is used to generate an alternating magnetic field that can enter the dielectric window 1 so as to induce an eddy current electric field for accelerating the collision of free electrons with the process gas to generate plasma.

[0040] In one embodiment, such as Figure 1 As shown, the movable shield 3 is arranged around the dielectric window 1 and the induction coil 2, and can move up and down or extend and retract along the axial direction of the dielectric window 1. During the plasma ignition stage, the movable shield 3 moves to a position where its orthographic projection structure on the dielectric window 1 is offset from the orthographic projection structure of the induction coil 2 on the dielectric window 1, so that the alternating magnetic field generated by the induction coil 2 can penetrate into the dielectric window 1. After the plasma ignition is completed, the movable shield 3 returns to its original position between the dielectric window 1 and the induction coil 2, and its orthographic projection structure on the dielectric window 1 covers the orthographic projection structure of the induction coil 2 on the dielectric window 1, so as to shield and protect the dielectric window 1.

[0041] This embodiment dynamically removes the movable shield 3 between the dielectric window 1 and the induction coil 2 during the plasma ignition stage. This prevents the movable shield 3 from blocking the alternating magnetic field from penetrating the dielectric window 1, thus ensuring the efficiency and success rate of plasma ignition. After plasma ignition, the movable shield 3 is immediately reset to cover the induction coil 2, providing effective shielding for the dielectric window 1 and preventing high-energy ions (especially hydrogen ions) generated by capacitive coupling between the induction coil 2 and the plasma from bombarding the dielectric window 1. This dynamic alternating magnetic field working mechanism of "passing through during ignition and shielding during steady state" solves the contradiction between ignition efficiency and long-term shielding protection that traditional static Faraday shielding struggles to balance, while ensuring ignition efficiency. This reduces the erosion rate of the dielectric window 1, decreases particulate contamination, extends equipment lifespan, and improves process yield.

[0042] In one embodiment, such as Figure 1 and Figure 2As shown, the movable shield 3 includes several annular shielding parts 31 arranged sequentially along the axial direction. The annular shielding part 31 closest to the processing chamber 4 is connected to the top of the processing chamber 4. The annular shielding part 31 closest to the processing chamber 4 is the one closest to the top of the processing chamber 4. Any two adjacent annular shielding parts 31 include a first annular shielding part and a second annular shielding part. The mating end of the first annular shielding part is provided with an axially extending receiving groove 32. At least a portion of the second annular shielding part is slidably inserted into the receiving groove 32 and can move towards or away from the bottom of the receiving groove 32 to reduce or increase the overall axial height of the movable shield 3. This nested telescopic annular shielding part 31 design allows the movable shield 3 to achieve reliable, stable, and compact adjustment of its axial height.

[0043] During the plasma ignition stage, the annular shield 31 located at the axially upward position among the two adjacent annular shields is driven to move axially. By nesting and sliding (such as the second annular shield located at the axially upward position sliding into the receiving groove 32 of the first annular shield located at the axially downward position), the total height of the first and second annular shields is compressed. By adjusting the height of multiple adjacent annular shields 31, the overall axial height of the movable shield 3 is adjusted, thereby making the entire movable shield 3 "shorter". This causes the orthographic projection structure of the movable shield 3 on the dielectric window 1 to fall below the orthographic projection structure of the induction coil 2 on the dielectric window 1 (which can be understood as the annular shield 31 shrinking from top to bottom, so that the final movable shield 3 is shortened to the position below the plane where the induction coil 2 is located), ensuring that the alternating magnetic field generated by the induction coil 2 directly enters the dielectric window 1. After ignition, the reverse drive causes the annular shield 31 to extend and reset, restoring its complete height so that the orthographic projection structure of the movable shield 3 on the dielectric window 1 covers the orthographic projection structure of the induction coil 2 on the dielectric window 1. This telescopic structure of the movable shield 3 occupies little space, moves smoothly in the axial direction, and the nested design of multiple annular shielding parts 31 can maintain good mechanical coaxiality in both the contracted and extended states, ensuring accurate switching of shielding effect and magnetic field path.

[0044] In one embodiment, the annular shielding portion 31 may also retract from bottom to top, which will not be described in detail here.

[0045] In one embodiment, the first annular shield and the second annular shield are in Figure 2In the example, it can be understood that in two adjacent annular shielding portions 31, the upper annular shielding portion 31 is the second annular shielding portion, and the lower annular shielding portion 31 is the first annular shielding portion. Except for the uppermost annular shielding portion 31, the mating ends (facing the upper end) of all other annular shielding portions 31 have receiving grooves 32 to mate with the annular shielding portion 31 located above it. A portion (facing the lower end), or even the entire annular shielding portion 31, is slidably inserted into the receiving grooves 32 of the annular shielding portion 31 located below it, thereby achieving contraction from top to bottom and ultimately adjusting the overall height of the movable shielding member 3 in the axial direction.

[0046] In one embodiment, the cavity of the receiving groove 32 is an annular structure that matches the shape of the second annular shield to which it is inserted.

[0047] In one embodiment, such as Figure 2 As shown, the receiving groove 32 has an axially extending anti-detachment groove 5 on its side wall near the opening end. The second annular shield has an anti-detachment block 6 on its side wall near its insertion end. The anti-detachment block 6 is slidably disposed within the anti-detachment groove 5 to prevent the second annular shield from detaching from the receiving groove 32. The cooperation between the anti-detachment block 6 and the anti-detachment groove 5 constitutes a structure combining axial sliding guidance and mechanical limiting. When the movable shield 3 performs telescopic movement, the anti-detachment block 6 slides along the anti-detachment groove 5, ensuring that the movement trajectory of the second annular shield within the receiving groove 32 is a stable axial straight line, preventing deflection or jamming during movement. More importantly, when the telescopic movement reaches its limit position (for example, when the second annular shield is about to completely detach from the receiving groove 32 in the extended state, or when the anti-detachment block 6 reaches the bottom of the anti-detachment groove 5 in the compressed state), the end of the anti-detachment groove 5 can prevent the anti-detachment block 6 from continuing to move, thereby effectively preventing the second annular shield from accidentally detaching from the receiving groove 32 or its plug-in end from colliding with the bottom of the receiving groove 32 in the compressed state, ensuring the reliability and integrity of the entire multi-layer nested structure and avoiding equipment failure caused by component separation.

[0048] In one embodiment, the mating end and the insertion end are both opposite ends of two adjacent annular shielding portions 31, that is, the axially symmetrical ends of an annular shielding portion 31 are the mating end and the insertion end, wherein the mating end of the uppermost annular shielding portion 31 is suspended, and the insertion end of the lowermost annular shielding portion 31 is connected to the top of the processing chamber 4. Specifically, as shown... Figure 2As shown, the mating end of the first annular shield is located at the upper end of the first annular shield, and the receiving groove 32 is a groove that is axially recessed from the end face of the upper end in a direction away from the end face. The insertion end of the second annular shield is located at the lower end of the second annular shield, and it is used to slide into the receiving groove 32 of the first annular shield. Moreover, the upper end of the second annular shield is the mating end and is provided with a receiving groove 32 that mates with the insertion end of the annular shield 31 located above the second annular shield.

[0049] The process of the overall height of the movable shield 3 decreasing is as follows: First, the uppermost annular shield 31 moves into the receiving groove 32 of the lower annular shield 31. When the anti-detachment block 6 touches the bottom wall of the anti-detachment groove 5, the annular shield 31 containing the uppermost annular shield 31 will continue to move into the receiving groove 32 of the lower annular shield 31. This process is repeated until the overall height of the movable shield 3 decreases.

[0050] In one embodiment, such as Figure 1 As shown, the annular shield 31 furthest from the top of the processing chamber 4 is the third annular shield. This third annular shield is connected to the axial drive 7. The axial drive 7 drives the third annular shield to move axially toward or away from the bottom of the receiving groove 32 of the annular shield 31 below it. The driving force is transmitted sequentially through the nested sliding fit between the annular shields 31, causing the annular shield 31 in the upper position to slide within the receiving groove 32 of the annular shield 31 in the lower position, thereby reducing or increasing the overall axial height of the movable shield 3. In this embodiment, the axial drive 7 drives the third annular shield to move axially, and its thrust or pull is transmitted sequentially through the nested annular shields 31, ultimately driving the second annular shield to slide within the receiving groove 32 of the first annular shield, thus achieving flexible adjustment of the overall height of the movable shield 3. This "top-driven, linked telescopic" design simplifies the drive structure, requiring only one component to apply driving force to control the entire shielding assembly, thus reducing complexity and cost. On the other hand, the power transmission path is clear, reliably converting the linear motion of the axial drive component 7 into the telescopic movement of the entire nested structure.

[0051] In one embodiment, the axial drive member 7 can be disposed on the top of the processing chamber 4 or on its external structure, and connected to the top or side of the third annular shield (i.e., the annular shield 31 located on top of the movable shield 3). The drive end 8 of the axial drive member 7 (such as a push rod or connecting rod) acts directly on the third annular shield. By precisely controlling the movement of the axial drive member 7 (such as a motor-driven lead screw, hydraulic cylinder, or pneumatic cylinder), the third annular shield can be driven to move up and down precisely along the axial direction (i.e., in a direction parallel to the central axis of the medium window 1), thereby enabling the entire movable shield 3 to achieve overall height adjustment through its linkage with the nested annular shield 31 below.

[0052] In one embodiment, the reaction chamber for plasma processing further includes a first sensor and a first processor. The first processor is connected to the axial drive 7 and the first sensor, respectively. The first sensor is disposed inside or outside the dielectric window 1 to collect the plasma concentration inside the dielectric window 1. According to the ignition command signal, the first processor controls the axial drive 7 to drive the movable shield 3 to extend and retract along the axial direction of the dielectric window 1. After the plasma concentration is greater than or equal to a preset threshold, the processor controls the axial drive 7 to drive the movable shield 3 to reset between the dielectric window 1 and the induction coil 2 to shield and protect the dielectric window 1.

[0053] In this embodiment, the configuration of the first sensor and the first processor enables automated and intelligent control of the plasma ignition and shielding protection process. By monitoring the plasma concentration and ignition command signal within the medium window 1 in real time through the first sensor, the system can automatically control the axial drive component 7 upon receiving the ignition command, causing the movable shield 3 to move to allow magnetic field penetration and assist ignition. Once the first sensor detects that the plasma concentration has reached a preset threshold (indicating successful plasma ignition and a stable state), the first processor immediately issues a command to drive the movable shield 3 to automatically reset to its shielding position. This closed-loop control mechanism based on real-time detection ensures the accuracy and timeliness of the movable shield 3's state switching, avoiding delays or misjudgments caused by manual operation. While ensuring efficient ignition, it can immediately protect the medium window 1 once the plasma reaches the working concentration, greatly improving the reliability and repeatability of the process and facilitating fully automated and safe operation of the equipment.

[0054] In one embodiment, the preset threshold can be a pre-set critical density value used to determine whether the plasma has been successfully excited and entered a stable state. This threshold is usually pre-calibrated experimentally based on specific process parameters such as process gas, reaction chamber pressure, and radio frequency power, and will not be elaborated here.

[0055] In one embodiment, the first sensor may be an optical emission spectrometer sensor, a Langmuir probe, or a plasma optical density sensor, etc. This sensor is positioned inside the dielectric window 1 (e.g., to detect plasma emission through an observation window) or outside the dielectric window 1 (e.g., to detect the intensity of light of a specific wavelength transmitted from the dielectric window 1), and is used to acquire signals reflecting the plasma concentration (or density) within the dielectric window 1 in real time and transmit them to the first processor. When the first processor analyzes and determines that the plasma concentration is greater than or equal to the preset threshold, it will trigger a reset command for the active shield 3.

[0056] In one embodiment, the first processor may be a programmable logic controller, a microprocessor, or a central processing unit. It is connected to the axial drive 7 and the first sensor, and is used to receive an externally input ignition command signal and plasma concentration information transmitted by the first sensor, and to control the axial drive 7 to move according to the ignition command signal and plasma concentration information to drive the movable shield 3 to move (perform lifting or telescopic movements).

[0057] In one embodiment, such as Figure 3 As shown, a first slit 33 extending circumferentially is provided through the first annular shield, and a second slit 34 extending axially is provided through the second annular shield. Several of the first slit 33 and the second slit 34 are provided and arranged axially. When the movable shield 3 is reset between the dielectric window 1 and the induction coil 2, the first slit 33 and the second slit 34 located in the overlapping area of ​​the first annular shield and the second annular shield overlap to form a first channel for the alternating magnetic field to enter the dielectric window 1. The first slit 33 and the second slit 34 located in the non-overlapping area of ​​the first annular shield and the second annular shield independently form a second channel for the alternating magnetic field to enter the dielectric window 1.

[0058] In this embodiment, when the movable shield 3 is reset between the dielectric window 1 and the induction coil 2 to shield the dielectric window 1, the adjacent two annular shields 31 will partially overlap due to their nested arrangement. The first slit 33 and the second slit 34 on the overlapping shields of the two annular shields 31 are partially or completely aligned with each other, forming a dedicated "window" or channel that allows the alternating magnetic field to pass through, ensuring that the plasma can continuously obtain energy during the steady-state process. In the shields where the two annular shields 31 do not overlap, the first slit 33 and the second slit 34 of each shield independently serve as alternating magnetic field channels. This design cleverly utilizes the axial offset characteristics of the multi-layer nested shields, so that when the movable shield 3 is performing its shielding function, the slit array on it provides a sufficient penetration path for the alternating magnetic field. This ensures effective electrostatic shielding of the dielectric window 1 (blocking high-energy ion bombardment) without excessively hindering the entry of the magnetic field, thus ensuring the stable maintenance of the plasma.

[0059] In one embodiment, both the first slit 33 and the second slit 34 include a plurality of sub-slits spaced apart along the circumference, that is, a plurality of sub-slits are provided in multiple circumferential regions of the first annular shield and the second annular shield located at different axial heights.

[0060] In one embodiment, the induction coil 2 includes a plurality of annular segments spaced apart along the axial direction, and a connecting segment connecting two adjacent annular segments. When the movable shield 3 is reset between the dielectric window 1 and the induction coil 2, the orthographic projection structure of the sub-slits on the dielectric window 1 is located between the orthographic projection structures of two adjacent annular segments on the dielectric window 1, and the orthographic projection structure of the connecting segment on the dielectric window 1 is located between the orthographic projection structures of two circumferentially adjacent sub-slits on the dielectric window 1. This is to physically block the electric field path between the low-potential ionized ions in the dielectric window 1 and the induction coil 2, which is at a high potential when energized, while forming a channel for the alternating magnetic field to enter the dielectric window 1, thereby preventing the accelerated ionized ions from bombarding the inner wall of the dielectric window 1.

[0061] This embodiment achieves synergistic optimization of the magnetic field channel and electric field shielding by precisely aligning the spatial arrangement of the annular segment and connecting segment of the induction coil 2 with the position of the sub-slits on the movable shield 3. Specifically, the annular segment of the induction coil 2 is the main part that generates the alternating magnetic field, and the sub-slit channel on the movable shield 3 is located between two adjacent annular segments. This allows the magnetic field generated by the annular segment to pass through the sub-slits and enter the dielectric window 1 to maintain the plasma. Moreover, the connecting segment of the induction coil 2 is located between two adjacent sub-slits, which means that when the induction coil 2 is energized, the connecting segment, which is at a high potential, is spatially offset from the sub-slit channel that allows the magnetic field to pass through (which is also the potential electric field path for low-potential ionized ions in the plasma). This spatially staggered design can physically block the direct electric field coupling path between low-potential ionized ions in the plasma and the high-potential connecting and annular sections when energized. This effectively prevents ions from being accelerated by the electric field and directly bombarding the inner wall of the dielectric window 1. It solves the problem that in traditional Faraday shielding, there is still electric field concentration and susceptibility to ion bombardment at the intersection of the slit and the coil connecting section. This application greatly enhances the protection of the dielectric window 1 while ensuring the magnetic field penetration efficiency.

[0062] In one embodiment, such as Figure 4 As shown, the movable shield 3 includes a pneumatic telescopic shield tube 9 and an air-filling component 10; the pneumatic telescopic shield tube 9 is located at the top of the processing chamber 4, and an air storage cavity is provided inside its tube wall; the air-filling component 10 is connected to the air storage cavity, so as to fill the air storage cavity with air through the air-filling component 10, so that the pneumatic telescopic shield tube can perform telescopic movement.

[0063] In one embodiment, the movable shield 3 further includes a second sensor and a second processor. The second processor is connected to the gas pumping component 10 and the second sensor. The second sensor is disposed inside the medium window 1 to collect the plasma concentration inside the medium window 1. The second processor controls the gas pumping component 10 to pump air from the gas storage chamber of the pneumatic telescopic shield tube 9 according to the ignition command signal, causing the pneumatic telescopic shield tube 9 to contract. This causes the orthographic projection structure of the pneumatic telescopic shield tube 9 on the medium window 1 after contraction to be offset from the orthographic projection structure of the induction coil 2 on the medium window 1. After receiving that the plasma concentration is greater than or equal to a preset threshold, the processor controls the gas pumping component 10 to pump air into the gas storage chamber of the pneumatic telescopic shield tube 9, causing the pneumatic telescopic shield tube 9 to return to the position between the medium window 1 and the induction coil 2, thereby providing shielding protection for the medium window 1.

[0064] This embodiment uses a pneumatic telescopic shielding tube 9 instead of a mechanical nesting structure, providing a simpler, faster-responding, and better-sealing movable shielding solution. Upon receiving the ignition command, the second processor controls the pumping and filling component 10 to extract air from the gas storage chamber of the pneumatic telescopic shielding tube 9, causing it to contract axially and quickly move away from between the dielectric window 1 and the induction coil 2, ensuring the alternating magnetic field penetrates to complete plasma ignition. Simultaneously, the second sensor monitors the plasma concentration within the dielectric window 1 in real time. When a preset threshold is reached (indicating successful ignition), the second processor immediately controls the pumping and filling component 10 to fill the gas storage chamber, causing the pneumatic telescopic shielding tube 9 to quickly and smoothly reposition and extend, precisely shielding between the dielectric window 1 and the induction coil 2, providing comprehensive shielding protection. This pneumatic control method has a compact structure, no complex mechanical linkage components, smooth movement, and is easy to seal, making it particularly suitable for vacuum or special gas environments in reaction chambers, and enabling fast and reliable automatic control.

[0065] In one embodiment, the second sensor has the same structure and principle as the first sensor, and the second processor has the same structure and principle as the first processor, which will not be described again here.

[0066] In one embodiment, the gas pumping / filling component 10 can be a combination of an air pump, a vacuum pump, and a filling valve, or a pneumatic actuator capable of providing controllable positive and negative pressure. It is connected to the gas storage chamber inside the pneumatic telescopic shielding tube 9 via a pipeline and is controlled by the second processor. Based on received control commands (such as control commands sent by the second processor based on ignition commands or plasma concentration information), the gas pumping / filling component 10 can perform actions to either pump air from the gas storage chamber (causing the pneumatic telescopic shielding tube 9 to contract) or fill air into the gas storage chamber (causing the pneumatic telescopic shielding tube 9 to extend), thereby precisely driving the pneumatic telescopic shielding tube 9 to contract and reposition during the ignition phase and reset its shielding position during the steady-state phase.

[0067] In one embodiment, the induction coil 2 includes a plurality of annular segments spaced apart along the axial direction, and a connecting segment connecting two adjacent annular segments. The pneumatic telescopic shielding tube 9 is provided with a plurality of third slits extending circumferentially to form a third channel for the alternating magnetic field to enter the dielectric window 1. The third slits are located between two adjacent annular segments, and the orthographic projection structure of the third slits on the dielectric window 1 is offset from the orthographic projection structure of the connecting segment on the dielectric window 1. This is to physically block the electric field path between the low-potential ionized ions in the dielectric window 1 and the induction coil 2, which is at a high potential when energized, while forming a channel for the alternating magnetic field to enter the dielectric window 1, thereby preventing the accelerated ionized ions from bombarding the inner wall of the dielectric window 1. In this embodiment, the number, arrangement, and function of the third slit are the same as those of the first slit 33 and the second slit 34. For example, the third slit also includes several sub-slits in the circumferential direction. When the movable shield 3 is reset between the dielectric window 1 and the induction coil 2, the orthographic projection structure of the sub-slits on the dielectric window 1 is located between the orthographic projection structures of two adjacent annular segments on the dielectric window 1. The orthographic projection structure of the connecting segment on the dielectric window 1 is located between the orthographic projection structures of two circumferentially adjacent sub-slits on the dielectric window 1. This will not be elaborated further here.

[0068] In one embodiment, such as Figure 5 As shown, the movable shield 3 also includes several guide members 11. These guide members 11 are arranged in a ring at equal intervals on the top of the processing chamber 4 and extend axially. The pneumatic telescopic shield tube 9 has several axially penetrating guide holes on its wall. These guide holes are not connected to the air storage chamber. Each guide member 11 is movably positioned within one of the guide holes to guide the pneumatic telescopic shield tube 9 during axial telescopic movement. The cooperation between the guide members 11 and the guide holes provides precise and stable axial movement guidance for the pneumatic telescopic shield tube 9. The guide members 11 are fixed to the top of the processing chamber 4 and extend axially, while the guide holes on the wall of the pneumatic telescopic shield tube 9 are isolated from the air storage chamber and do not affect its airtightness. When the inflation / extension unit 10 drives the pneumatic telescopic shield tube 9 to telescopically move, the guide members 11 slide within the guide holes, effectively limiting the radial sway, twisting, or wobbling of the pneumatic telescopic shield tube 9, ensuring that it only moves in a straight line along the axial direction. This not only ensures the positional accuracy of the pneumatic telescopic shielding tube 9 during the contraction and resetting process, allowing its projection structure on the medium window 1 to accurately switch between "misalignment" and "coverage," thereby reliably achieving magnetic field penetration and shielding functions, but also reduces wear, sealing failure, or interference with surrounding components (such as induction coil 2) caused by unstable movement, thus improving the reliability and service life of the equipment.

[0069] In one embodiment, the shape of the guide member 11 and the cavity shape of the guide hole can be a matching cylindrical, square, polygonal, or any non-circular cross-sectional shape (e.g., rectangular, elliptical, D-shaped, etc.). The guide member 11 (e.g., a guide rod) is fixed to the top of the processing chamber 4, and its cross-sectional shape matches the cavity shape of the guide hole opened on the wall of the pneumatic telescopic shielding tube 9. This close fit of shapes allows the guide member 11 to slide smoothly within the guide hole, providing precise linear guidance for the axial telescopic movement of the pneumatic telescopic shielding tube 9, while effectively constraining its degrees of freedom in the radial and circumferential directions, preventing the pneumatic telescopic shielding tube 9 from deflecting, swaying, or spinning during movement, ensuring the stability and positioning accuracy of its movement trajectory.

[0070] Of course, in other embodiments, the movable shield 3 is an integral structure and does not have the function of telescopic or lifting movement, that is, the whole is a rigid structure; in this embodiment, the movable shield 3 is driven by a driving device to move its whole body upward and downward in the axial direction. During the upward movement, the movable shield 3 moves above the induction coil 2, which is suitable for the ignition stage. After ignition is completed, the movable shield 3 is driven to reset between the medium window 1 and the induction coil 2 to shield and protect the medium window 1. The specific movement process and principle are similar to those described above, and will not be repeated here.

[0071] To address the problems existing in the prior art, embodiments of the present invention also provide a semiconductor processing apparatus, such as... Figure 1 As shown, the semiconductor processing equipment includes a reaction chamber for plasma processing, a process gas supply system, a vacuum system, and a radio frequency power supply; the process gas supply system is connected to the dielectric window 1 to supply process gas into the dielectric window 1; the vacuum system is connected to the dielectric window 1 to extract gas from the dielectric window 1 and maintain the required vacuum level of the dielectric window 1; the radio frequency power supply is electrically connected to the induction coil 2.

[0072] In one embodiment, the semiconductor processing equipment can be various plasma process equipment for wafer processing, such as, but not limited to, inductively coupled plasma etching equipment, plasma-enhanced chemical vapor deposition equipment, and plasma resist stripping (or plasma cleaning) equipment. These devices all include the aforementioned reaction chamber for plasma processing, which commonly uses an induction coil 2 to excite plasma. A movable shield 3, as described in this invention, is removed during the ignition phase to allow magnetic field penetration and reset during the process phase to protect the dielectric window 1. This makes it suitable for processes sensitive to the erosion of the dielectric window 1, such as high-hydrogen processes, thereby improving equipment lifespan and process yield.

[0073] 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 for plasma processing, characterized in that, Includes dielectric window, induction coil, and movable shield; The medium window is located at the top of the processing chamber; The induction coil is arranged around the outside of the dielectric window and connected to the external radio frequency power supply. It is used to generate an alternating magnetic field that can enter the dielectric window so as to induce an eddy current electric field through the alternating magnetic field to accelerate the collision of free electrons with the process gas to generate plasma. The movable shield is arranged around the medium window and the induction coil, and can move up and down or extend and retract along the axial direction of the medium window. During the plasma ignition stage, the movable shield moves to a position where its orthographic projection structure on the dielectric window is offset from the orthographic projection structure of the induction coil on the dielectric window, so that the alternating magnetic field generated by the induction coil can penetrate into the dielectric window. After plasma ignition is completed, the movable shielding component is reset between the dielectric window and the induction coil, and its orthographic projection structure on the dielectric window covers the orthographic projection structure of the induction coil on the dielectric window, so as to shield and protect the dielectric window. The movable shielding component consists of several annular shielding parts that are sequentially connected along the axial direction.

2. The reaction chamber for plasma processing according to claim 1, characterized in that, The annular shielding part near the processing chamber is connected to the top of the processing chamber; any two adjacent annular shielding parts include a first annular shielding part and a second annular shielding part, the mating end of the first annular shielding part is provided with a receiving groove extending along the axial direction, and at least part of the second annular shielding part is slidably inserted into the receiving groove, and can move toward or away from the bottom of the receiving groove to reduce or increase the overall height of the movable shielding part in the axial direction.

3. The reaction chamber for plasma processing according to claim 2, characterized in that, The receiving groove has an axially extending anti-detachment groove on its side wall near the opening end, and the second annular shield has an anti-detachment block on its side wall near its insertion end. The anti-detachment block is slidably disposed in the anti-detachment groove to prevent the second annular shield from detaching from the receiving groove.

4. The reaction chamber for plasma treatment according to claim 2, characterized in that, The annular shield that is furthest from the top of the processing chamber among the plurality of annular shields is the third annular shield. The third annular shield is connected to an axial drive member. The axial drive member drives the third annular shield to move axially toward or away from the bottom of the receiving groove of the annular shield below it. The driving force is transmitted sequentially through the nested sliding fit between the annular shields, so that the annular shield in the upper position slides in the receiving groove of the annular shield in the lower position, thereby reducing or increasing the overall height of the movable shield in the axial direction.

5. The reaction chamber for plasma processing according to claim 4, characterized in that, It also includes a first sensor and a first processor. The first processor is connected to the axial drive and the first sensor respectively. The first sensor is disposed inside or outside the medium window to collect the plasma concentration inside the medium window. According to the ignition command signal, the first processor controls the axial drive to drive the movable shield to perform telescopic movement along the axial direction of the medium window. After the plasma concentration is greater than or equal to a preset threshold, the processor controls the axial drive to drive the movable shield to reset between the medium window and the induction coil to shield and protect the medium window.

6. The reaction chamber for plasma treatment according to claim 2, characterized in that, The first annular shield is provided with a first slit extending circumferentially, and the second annular shield is provided with a second slit extending axially. There are a plurality of the first slit and the second slit, which are arranged axially. When the movable shield is reset between the dielectric window and the induction coil, the first slit and the second slit located in the overlapping area of ​​the first annular shield and the second annular shield overlap to form a first channel for the alternating magnetic field to enter the dielectric window. The first slit and the second slit located in the non-overlapping area of ​​the first annular shield and the second annular shield independently form a second channel for the alternating magnetic field to enter the dielectric window.

7. The reaction chamber for plasma processing according to claim 6, characterized in that, Both the first slit and the second slit include a plurality of sub-slits spaced apart circumferentially; The induction coil includes several annular segments arranged at intervals along the axial direction, and a connecting segment connecting two adjacent annular segments. When the movable shield is reset between the dielectric window and the induction coil, the orthographic projection structure of the sub-slits on the dielectric window is located between the orthographic projection structures of two adjacent annular segments on the dielectric window, and the orthographic projection structure of the connecting segment on the dielectric window is located between the orthographic projection structures of two circumferentially adjacent sub-slits on the dielectric window.

8. A semiconductor processing apparatus, characterized in that, include: A reaction chamber for plasma processing as described in any one of claims 1 to 7; A process gas supply system is connected to a medium window to supply process gas into the medium window; A vacuum system, connected to the medium window, is used to extract gas from the medium window and maintain the required vacuum level of the medium window; The radio frequency power supply is electrically connected to the induction coil.

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