Reaction chamber

Abstract

The utility model provides a kind of reaction chamber, heater is equipped in reaction chamber, protective cover, tray, rotating shaft and purging gas supply pipeline;Protective cover is equipped outside heater, protective cover includes opposite open end and closed end, heater is close to closed end, tray is located above closed end to be used to carry substrate, gas flow passage is enclosed with closed end between tray and closed end, and it is communicated with outside;The top end of rotating shaft is from open end and is movably penetrated closed end, and it is rotatably connected with tray to drive tray rotation, rotating shaft includes gas outlet shaft section in gas flow passage, and gas outlet shaft section is along circumferential and is equipped with several gas outlet holes;Purging gas supply pipeline is located in rotating shaft and is communicated with each gas outlet hole, to be used to transport purging gas to gas flow passage.The present application can effectively avoid the oxidation or corrosion of process gas to heater in process.

Description

Technical Field

[0001] This utility model relates to the field of semiconductor device manufacturing equipment technology, and in particular to reaction chambers. Background Technology

[0002] In semiconductor device manufacturing equipment, such as the reaction chamber of a metal-organic chemical vapor deposition (MOCVD) system, the wafer is typically placed on a graphite tray, which is mounted on a spindle, with a heater located below the tray. During the MOCVD process, the graphite tray rotates driven by the spindle, while the heater heats the tray. Process gases enter the reaction chamber from above the tray and flow onto the surface of the wafer on the tray to grow a thin film.

[0003] If the process gas contains oxidizing gases (such as oxygen) or corrosive gases (such as ammonia, HCl, Cl2, etc.), it will oxidize or corrode the components inside the reaction chamber, especially the heating components. For example, when using MOCVD process to grow oxide thin films (such as zinc oxide, tin oxide, gallium oxide, etc.), oxidizing reaction source gases are used.

[0004] To prevent process gases from oxidizing the heater, in low-temperature reactions, heaters typically use silicon- or aluminum-containing alloys as resistance wires. However, the performance is unstable, the heating range is relatively low, and it cannot meet process requirements. If the heater uses materials such as tungsten or rhenium, although heaters made of these materials can be used at high temperatures, they are easily oxidized or corroded by process gases, affecting the service life of the heater. Utility Model Content

[0005] The purpose of this invention is to provide a reaction chamber that can effectively prevent the oxidation or corrosion of the heater by process gases during the process, thereby improving efficiency.

[0006] To achieve the above objectives, the reaction chamber of this invention is provided with a heater, a protective cover, a tray, a rotating shaft, and a purge gas supply pipeline. The protective cover is disposed outside the heater and includes an open end and a closed end opposite to each other. The heater is located near the closed end, and the tray is positioned above the closed end to support the substrate. A gas flow channel communicating with the outside is formed between the tray and the closed end. The top end of the rotating shaft extends movably from the open end through the closed end and is rotatably connected to the tray to drive the tray to rotate. The rotating shaft includes an outlet shaft section located within the gas flow channel, and the outlet shaft section has several outlet holes circumferentially formed. The purge gas supply pipeline is disposed within the rotating shaft and communicates with each of the outlet holes to supply purge gas to the gas flow channel.

[0007] Preferably, the reaction chamber further includes several flow guiding structures, which are disposed on the structure enclosed by the bottom surface of the tray and the closed end, to further enhance the barrier effect on process gases.

[0008] Preferably, the bottom of the tray is provided with a shaft connection portion for connecting with the top end of the rotating shaft; a plurality of the flow guiding structures are radially arranged around the shaft connection portion on the bottom surface of the tray, and each flow guiding structure extends toward the outer edge of the tray.

[0009] Preferably, the flow guiding structure is a rib structure or a groove structure.

[0010] Preferably, the top surface of the tray is provided with a plurality of bearing grooves for bearing the substrate; the number of intersections between the orthographic projection of the rib structure on the top surface of the tray and each of the bearing grooves is 0.

[0011] Preferably, the flow guiding structure is straight in the radial direction.

[0012] Preferably, the flow guiding structure is curved in an arc shape in the radial direction.

[0013] Preferably, the closed end edge is surrounded by a baffle ring, and the baffle ring, the tray, and the closed end form the gas flow channel; the tray includes a body portion, the top of the body portion extends radially to form an extension portion, and the bottom of the body portion protrudes toward the closed end, and the extension portion shields the baffle ring.

[0014] Preferably, the inner wall of the partition ring has a multi-level stepped structure and / or the outer wall of the body has a multi-level stepped structure, so that a tortuous gap flow channel is formed between the inner wall of the partition ring and the outer wall of the body.

[0015] Preferably, the distance h between the bottom of the tray and the top of the protective cover and the diameter D of the vent hole satisfy the following condition: 1 / 2h ≤ D ≤ h.

[0016] Preferably, the number of air outlets is greater than or equal to 6 and less than or equal to 16.

[0017] The beneficial effects of the reaction chamber of this invention are as follows: (1) The protective cover in this application is provided outside the heater, and the heater is close to the closed end of the protective cover, which can prevent corrosive or oxidizing process gases from entering the space where the heater is located through the side wall of the protective cover.

[0018] (2) The tray of this application is located above the closed end to support the substrate. A gas flow channel communicating with the outside is formed between the tray and the closed end. The top end of the rotating shaft moves through the closed end from the open end and is rotatably connected to the tray to drive the tray to rotate, so that there is no motion interference between the tray and the protective cover. More importantly, the rotating shaft includes an exhaust shaft section located in the gas flow channel. The exhaust shaft section has several exhaust holes opened in the circumferential direction. The purge gas supply pipeline is located in the rotating shaft and communicates with each of the exhaust holes to deliver purge gas to the gas flow channel. This allows the purge gas to be continuously discharged from the gas flow channel to form a positive pressure air curtain, which can effectively prevent process gas from entering the protective cover through the gas flow channel, further improving the isolation effect on process gas. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of the reaction chamber in an embodiment of the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of the reaction chamber in an embodiment of the present invention. Figure 2 ; Figure 3 for Figure 1 A magnified schematic diagram of a portion of the purge gas supply line and rotating shaft in the reaction chamber shown. Figure 4 This is a schematic diagram of the tray and flow guiding structure in the reaction chamber of this utility model embodiment; Figure 5 This is a schematic diagram of the purge gas supply pipeline and rotating shaft in the reaction chamber of this utility model embodiment; Figure 6 This is a schematic diagram showing the flow direction of the purging gas in the gas channel in the reaction chamber of this utility model embodiment; Figure 7 This is a schematic diagram of the structure of the protective cover in the reaction chamber according to an embodiment of the present invention; Figure 8This is a cross-sectional view of the protective cover in the reaction chamber according to an embodiment of the present invention; Figure 9 This is a schematic diagram of the flow guiding structure in the reaction chamber of this utility model being disposed at the bottom of the tray. Figure 10 This is a schematic diagram of the structure of the reaction chamber of this utility model, in which the supporting groove is set on the top of the tray; Figure 11 This is a schematic diagram of the orthographic projection of the flow guiding structure and the supporting groove in the reaction chamber of this utility model onto the bottom surface of the tray.

[0020] Explanation of reference numerals in the attached figures: 1. Heater; 2. Gas flow channel; 3. Protective cover; 31. Closed end; 32. Through hole; 33. Baffle ring; 34. Receiving groove; 4. Tray; 41. Shaft connection; 42. Body; 43. Extension; 44. Bearing groove; 5. Rotating shaft; 51. Outlet shaft section; 52. Outlet hole; 53. Support shaft section; 54. Bearing part; 6. Purge gas supply pipeline; 61. Axial pipeline; 62. Radial pipeline; 7. Flow guiding structure; 8. Chamber body bottom plate. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this utility model pertains. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects.

[0022] To overcome the problems existing in the prior art, this utility model provides a reaction chamber that can effectively prevent the oxidation or corrosion of the heater by the process gas during the process, thereby improving the efficiency of use.

[0023] In some embodiments of this utility model, reference is made to Figures 1 to 11The reaction chamber is equipped with a heater 1, a protective cover 3, a tray 4, a rotating shaft 5, and a purge gas supply pipeline 6. The protective cover 3 covers the heater 1 and includes an open end and a closed end 31. The heater 1 is located near the closed end 31. The tray 4 is located above the closed end 31 to support the substrate. A gas flow channel 2 communicating with the outside is formed between the tray 4 and the closed end 31. The top end of the rotating shaft 5 extends movably through the closed end 31 from the open end and is rotatably connected to the tray 4 to drive the tray 4 to rotate. The rotating shaft 5 includes an outlet shaft section 51 located in the gas flow channel 2. The outlet shaft section 51 has several outlet holes 52 circumferentially opened. The purge gas supply pipeline 6 is located in the rotating shaft 5 and communicates with each of the outlet holes 52 to supply purge gas to the gas flow channel 2.

[0024] In this embodiment, reference Figure 7 and Figure 8 The top of the closed end 31 is provided with a through hole 32 for the rotating shaft 5 to pass through.

[0025] In this application, the protective cover 3 is a closed structure with one open end. A gas flow channel 2 is formed between the tray 4 and the protective cover 3, meaning that the tray 4 and the protective cover 3 do not contact each other, thus preventing the protective cover 3 from interfering with the rotation of the tray 4. Because the protective cover 3 covers the heater 1, and the heater 1 is close to the closed end 31 of the protective cover 3, the process gas cannot enter the space where the heater is located through the side wall of the protective cover 3. Therefore, the area of ​​components (especially the heater 1) inside the protective cover 3 that may come into contact with the process gas can be minimized to the greatest extent, effectively isolating oxidizing (or corrosive) process gases, avoiding oxidation or corrosion of the heater 1 by the process gas during the process, and improving the service life of the heater 1.

[0026] Even if process gas enters the gas flow channel 2 between the tray 4 and the protective cover 3, it still needs to pass through the through hole 32 between the rotating shaft 5 and the protective cover 3 to potentially enter the protective cover 3. In this application, the rotating shaft 5 includes an outlet shaft section 51 located within the gas flow channel 2. The outlet shaft section 51 has several outlet holes 52 circumferentially opened. The purge gas supply pipeline 6 is located within the rotating shaft 5 and communicates with each of the outlet holes 52 to supply purge gas to the gas flow channel 2. This allows the purge gas to continuously discharge outward from the edge of the gas flow channel 2, forming a positive pressure air curtain. This effectively prevents process gas from entering the protective cover 3 through the through hole 32 from the gas flow channel 2, further improving the isolation effect of the process gas.

[0027] In some embodiments of this utility model, Figure 1 , Figure 2 , Figure 7 and Figure 8 The protective cover 3 has an inverted barrel shape.

[0028] In some embodiments of this utility model, reference is made to Figure 9 The reaction chamber also includes several flow guiding structures 7, which are located on the bottom surface of the tray 4 and the enclosed end 31 to further enhance the barrier effect on process gases.

[0029] In this embodiment, since the rotating shaft 5 drives the tray 4 to rotate at high speed (e.g., speed ≥ 100 RPM), several flow guiding structures 7 are provided in the gas flow channel 2. During the synchronous rotation of the tray 4 driven by the rotating shaft 5, the flow guiding structures 7 can generate a strong driving force for the gas in the gas flow channel 2 to flow from the center to the edge. This makes the flow guiding structures 7 act like blades in a centrifugal pump, which is conducive to forming an efficient radial purging airflow. This can push the purging gas from the center of the gas flow channel 2 to the edge, thereby establishing a pressure gradient along the center to the edge of the gas flow channel 2, which can effectively prevent the process gas from flowing away from the edge of the tray 4. The gas flow channel 2 is insulated from oxidizing (or corrosive) process gases to the greatest extent, further preventing oxidation or corrosion of heater 1 by process gases during the process. Especially for reaction chambers using oxidizing process gases, heater 1 made of materials such as tungsten, rhenium, or graphite can be selected to meet the process requirements of heating to a maximum temperature of 1600℃, effectively ensuring the service life of heater 1 and improving the uptime and efficiency of MOCVD. Moreover, compared with static purging that relies on pressure difference diffusion, this method is powerful and directional, effectively removing stagnant areas in the gas flow channel 2 and eliminating gas dead zones. At the same time, the gas flow channel 2 between tray 4 and protective cover 3, combined with the continuous flow of purging gas, enhances the convective heat transfer at the bottom of tray 4, helps to equalize the local temperature differences that may be caused by the radiation of heater 1, and promotes a more uniform temperature field on tray 4 carrying the substrate, thereby directly improving the uniformity of thin film deposition or heat treatment processes. In addition, the centrifugal drive generates a stable and symmetrical radial airflow, avoiding random disturbances caused by external gas source fluctuations or chamber pressure changes. The stable and controllable flow field provides a reliable lower boundary condition for the process gas flow field above tray 4, which is conducive to the stability of the process environment in the entire reaction chamber and improves batch repeatability.

[0030] In some specific embodiments of this utility model, reference is made to Figure 9 The flow guiding structure 7 is fixed to the bottom surface of the tray 4, so that the flow guiding structure 7 rotates with the tray 4 to generate driving force. That is, the driving energy of the flow guiding structure 7 comes directly from the same main shaft that provides power for the rotation of the tray 4. There is no need to set up an additional independent external driving mechanism or control circuit, which greatly simplifies the structure inside the chamber, realizes the efficient reuse of energy, and the system has a high energy efficiency ratio.

[0031] In other specific embodiments of this utility model, the flow guiding structure 7 is circumferentially fixed to the surface of the outlet shaft section 51 so as to drive the purge gas in the gas flow channel 2 to flow from the center to the edge of the gas flow channel 2 by rotating synchronously with the rotating shaft 5. Further, the flow guiding structure 7 is located on the outlet path of the outlet hole 52, and the flow guiding structure 7 extends along the direction away from the outlet shaft section 51 of the rotating shaft 5.

[0032] In some embodiments of this invention, the purging gas flowing out through the gas channel 2 is finally discharged together with the process gas in the reaction chamber into the exhaust pipe.

[0033] In some embodiments of this utility model, the other end of the purge gas supply pipeline 6 is connected to the purge gas supply end, and the purge gas is an inert gas.

[0034] In some embodiments of this utility model, reference is made to Figures 1 to 4 , Figure 9 The bottom of the tray 4 is provided with a shaft connecting portion 41 for engaging with the top end of the rotating shaft 5. In some specific embodiments, the shaft connecting portion 41 is a recess (e.g., Figures 1 to 4 , Figure 9 (as shown), boss or mating hole.

[0035] In some embodiments of this utility model, reference is made to Figures 1 to 3 , Figure 5 The rotating shaft 5 further includes a support shaft section 53 and a bearing portion 54 located at both ends of the air outlet shaft section 51, respectively. The support shaft section 53 is connected to a drive mechanism (not shown), and the bearing portion 54 is connected to the shaft connection portion 41 of the tray 4. In some specific embodiments, the bearing portion 54 is frustum-shaped (e.g., Figure 1 and Figure 2 As shown), and adapted to the recess.

[0036] In some embodiments of this utility model, reference is made to Figures 1 to 3 , Figure 5 The purging gas supply line 6 includes an axial line 61 and several radial lines 62. The axial line 61 is arranged axially on the support shaft section 53, and the radial lines 62 are arranged radially on the outlet shaft section 51. One end of the radial line 62 is connected to the axial line 61, and the other end is connected to the outlet hole 52.

[0037] In some embodiments of this utility model, the tray 4 is a graphite tray.

[0038] In some embodiments of this utility model, the rotating shaft 5 may be made of silicon carbide or molybdenum alloy.

[0039] In some embodiments of this utility model, reference is made to Figure 6 The distance h between the bottom of the tray 4 and the top of the protective cover 3 satisfies the following condition: 1 / 2h ≤ D ≤ h. The distance h between the bottom of the tray 4 and the top of the protective cover 3 is the axial height of the gas channel 2, allowing the purge gas to continuously discharge outwards from the edge of the gas channel 2, forming a positive pressure air curtain to prevent process reaction gases and byproduct particles from penetrating or diffusing into the gas channel 2 and the area where the heater 1 is located. The height h of the gas channel 2 should ideally not affect the rotation of the tray 4; the smaller the height h of the gas channel 2, the better.

[0040] In some embodiments of this utility model, reference is made to Figures 1 to 3 , Figure 5 and Figure 6 The number of vent holes 52 is greater than or equal to 6 and less than or equal to 16. When the number of vent holes 52 is less than 6, too little purge gas is discharged into the gas flow channel 2, limiting the blocking effect on the process reaction gas. When the number of vent holes 52 is greater than 16, it will affect the rigidity of the rotating shaft 5, thereby affecting the service life of the rotating shaft 5.

[0041] In some embodiments of this utility model, reference is made to Figure 4 and Figure 9 Several flow guiding structures 7 are radially arranged around the shaft connection portion 41 on the bottom surface of the tray 4, and each flow guiding structure 7 extends toward the outer edge of the tray 4. That is, each flow guiding structure 7 has an inner end and an outer end, the inner end of each flow guiding structure 7 is close to and around the shaft connection portion 41, and the outer end of each flow guiding structure 7 extends toward the outer edge of the tray 4.

[0042] In this embodiment, the flow guiding structure 7 is located at the bottom of the tray 4, providing robust stability and ensuring the smoothness of the tray 4 during high-speed rotation. This reduces vibration and ensures good dynamic balance during high-speed rotation, thereby facilitating a more stable and controllable flow field for the purge gas. Furthermore, the flow guiding structure 7 is radially positioned around the shaft connection 41 at the bottom of the tray 4, forming a series of separated radial flow guiding channels radiating from the center to the edge. This allows the flow guiding structure 7 to not only generate centrifugal force through rotation but also function as a flow guide plate, physically regulating and guiding the gas flow path. This effectively prevents circumferential crossflow of the purge gas, ensuring that the majority of the purge gas is efficiently guided to the edge of the gas flow channel 2, maximizing the driving effect of centrifugal force. In addition, the inner end of each of the flow guiding structures 7 is located on the periphery of the shaft connection 41, so that the purge gas is captured and forced into the strong centrifugal force field created by the high-speed flow guiding structure 7 the moment it is ejected from the air outlet 52 on the side of the rotating shaft 5 and enters the gas flow channel 2. This reduces the turbulence or diffusion of the gas in the central region to the maximum extent, which is beneficial to improving the directional flow and initial velocity of the purge gas.

[0043] In some embodiments of this utility model, the flow guiding structure 7 is evenly distributed circumferentially around the bottom of the tray 4 with the axis of rotation 5 as the center.

[0044] In some embodiments of this utility model, reference is made to Figure 4 and Figure 9 The flow guiding structure 7 is a ribbed structure. The protruding sidewalls of the ribbed structure can effectively guide the airflow, form a clear flow channel boundary, and reduce turbulence.

[0045] In some embodiments of this utility model, the convex rib structure protrudes outward from the bottom surface of the tray 4, so that there is no moving connecting part between the flow guiding structure 7 and the tray 4. It has good rigidity, excellent dynamic balance and high reliability under high speed rotation. Moreover, the convex rib structure itself can serve as a reinforcing rib to enhance the structural rigidity and deformation resistance of the bottom of the tray 4, which is especially suitable for large-sized or high-speed rotating trays 4.

[0046] In other embodiments of this invention, the flow guiding structure 7 is a groove structure. Further, the groove structure is recessed inward from the bottom surface of the tray 4. The groove structure and the tray 4 body are an integral structure without any connecting interface, eliminating the risk of blade detachment due to connection failure (such as welding cracks), providing the highest mechanical reliability and stability, and is particularly suitable for semiconductor process environments with extremely high cleanliness and reliability requirements. Moreover, the bottom of the tray 4 (except inside the groove structure) remains a continuous plane without protrusions, which to some extent reduces the corners where particles accumulate and makes cleaning and maintenance more convenient. Simultaneously, the purge gas flowing within the groove structure can also be guided by the sidewalls of the groove structure and accelerated radially along the groove due to centrifugal force.

[0047] Whether the flow guiding structure 7 described in this application is a ribbed structure or a grooved structure, it can constrain the airflow through physical boundaries and pump the purge gas at the bottom of the tray 4 to the edge of the tray 4 by means of rotation, thereby effectively achieving the purpose of "centrifugal flow guidance". It has a wide range of applications, allowing for optimal selection based on manufacturing costs, tray 4 materials, production batches, and reliability preferences. For example, for a single tray 4 with high reliability requirements, a grooved structure can be machined; for a tray 4 that requires reinforced structure or composite materials, a ribbed structure can be used.

[0048] In some embodiments of this utility model, reference is made to Figure 4 , Figures 9 to 11 The top surface of the tray 4 is provided with several bearing grooves 44 for bearing the substrate (e.g., Figure 10 As shown), the number of intersections between the orthographic projection of the rib structure on the top surface of the tray 4 and each of the bearing grooves 44 is 0, that is, the orthographic projection of the rib structure on the top surface of the tray 4 and the orthographic projection of the bearing grooves 44 on the top surface of the tray 4 are staggered (e.g., Figure 11 As shown), they do not overlap. In other embodiments of this utility model, the number of intersection points between the orthographic projection of the groove structure on the top surface of the tray 4 and each of the supporting grooves 44 is 0, that is, the orthographic projection of the groove structure on the bottom surface of the tray 4 and the orthographic projection of the supporting grooves 44 on the bottom surface of the tray 4 are staggered and do not overlap. That is, when the rib structure or the groove structure is set on the bottom of the tray 4, it should avoid the setting position of the supporting grooves 44 on the top of the tray 4 to ensure the uniformity of the substrate heating temperature.

[0049] In some embodiments of this utility model, the rib structure can be formed by welding, inlaying, or integral casting / forging with the tray 4, which provides flexibility in manufacturing and integration and facilitates subsequent improvement or maintenance. For example, different wear-resistant or corrosion-resistant materials can be selected to manufacture the rib structure and then welded to the bottom of the tray 4.

[0050] In some embodiments of this utility model, the groove structure is formed directly on the bottom of the tray 4 by machining (such as milling) or molding.

[0051] In some embodiments of this invention, the flow guiding structure 7 is straight in the radial extension direction. The straight flow guiding structure is simple in structure, easy to manufacture, and can generate a direct and powerful radial centrifugal driving force. This allows the flow guiding structure 7 to drive the purge gas in a stable airflow direction, making it suitable for scenarios requiring direct and efficient gas flow lines.

[0052] In other embodiments of this invention, the flow guiding structure 7 is curved in an arc shape along the radial extension direction. The arc-shaped flow guiding structure has superior aerodynamic characteristics. A reasonable curved shape (e.g., the curvature similar to that of a centrifugal fan blade) can more smoothly guide the airflow direction, reducing eddies and impact losses caused by the separation of the purge gas from the blade surface. This helps to improve the pumping efficiency of the purge gas, increase flow rate, or reduce noise under the same rotational power consumption, and is beneficial for optimizing the flow field of the purge gas. Furthermore, when the flow guiding structure 7 is arc-shaped, the required curvature can be predetermined as needed.

[0053] In some embodiments of this utility model, the flow guiding structure 7 is arranged perpendicularly to the bottom surface of the tray 4 on its extension surface in a direction away from the bottom of the tray, so that the "scooping" and "pushing" effect on the airflow is most direct and the radial force component generated is the largest, which is especially beneficial for rapid start-up and establishment of a strong radial flow field.

[0054] In other embodiments of this utility model, the extension surface of the flow guiding structure 7 in the direction away from the bottom of the tray is set at an acute angle to the bottom surface of the tray 4. Even if the blade surface of the flow guiding structure 7 forms a certain angle with the rotation direction, the flow guiding structure 7 can better conform to the dynamic angle of gas inflow when rotating, reduce the inflow impact, and help improve the pumping efficiency of the purging gas; moreover, it can guide the gas to obtain radial velocity.

[0055] In some specific embodiments of this utility model, the cross-sectional shape of the rib structure or groove structure is rectangular, trapezoidal, or arc-shaped. The cross-section is a section formed along a direction perpendicular to the bottom surface of the tray 4.

[0056] In some embodiments of this utility model, reference is made to Figures 1 to 4 , Figures 6 to 8The closed end 31 is surrounded by a baffle ring 33, and the baffle ring 33, the tray 4, and the closed end 31 form the gas flow channel 2. The tray 4 includes a body portion 42, the top of which extends radially to form an extension portion 43, and the bottom of the body portion 42 protrudes toward the closed end, and the extension portion 43 covers the baffle ring 33. This creates a three-dimensional labyrinthine gas flow channel between the bottom of the main body 42 and the top of the closed end 31, between the outer wall of the main body 42 and the inner wall of the partition ring 33, and between the bottom of the extension 43 and the top of the partition ring 33 (when the extension 43 surrounds the partition ring 33, it also includes the area between the inner wall of the extension 43 and the outer wall of the partition ring 33). The purge gas flow direction is first radially outward, then axially upward, and finally radially outward (when the extension 43 surrounds the partition ring 33, it also includes the area axially downward). The purge gas flow direction is as follows: Figure 6 The direction indicated by the central arrow effectively prevents backflow of process gas, physically hindering the penetration or diffusion of process reaction gas and byproduct particles into the gas channel 2 and the area where heater 1 is located. At the same time, this channel structure does not require additional complex guide vanes or external gas channels. It cleverly utilizes the centrifugal force provided by the guide structure 7 as the airflow driving force, so that the purge gas flows naturally in the direction of centrifugal force in the channel. This allows the gas to be accelerated in an orderly manner in this labyrinthine gas channel and thrown from the center of the gas channel 2 to the edge. Moreover, the purge gas continuously discharged from the edge of the channel forms a positive pressure air curtain, which further actively blocks the reverse intrusion of pollutants.

[0057] In some embodiments of this utility model, reference is made to Figure 7 and Figure 8 The partition ring 33 extends upward and surrounds the top of the closed end 31 to form a receiving groove 34; the outer diameter of the body part 42 is smaller than the inner diameter of the receiving groove 34, and the outer diameter of the extension part 43 is larger than the outer diameter of the partition ring 33.

[0058] In some embodiments of this utility model, reference is made to Figure 1 , Figure 2 and Figure 6 The extension portion 43 extends radially outward from the outer periphery of the body portion 42. The extension portion 43 is suspended on the partition ring 33 and covers the upper end of the partition ring 33. That is, a radially outward flow channel is formed between the bottom of the extension portion 43 and the top of the partition ring 33.

[0059] In other embodiments of this utility model, the extension portion 43 extends radially outward and downward from the outer periphery of the body portion 42. The extension portion 43 is suspended on the partition ring 33 and surrounds at least a portion of the outer sidewall of the partition ring 33. That is, the extension portion 43 includes a lateral extension portion and an axial extension portion connected to the lateral extension portion. A radially outward flow channel is formed between the bottom of the lateral extension portion and the top of the partition ring 33. An axially downward flow channel is also formed between the inner sidewall of the axial extension portion and the outer sidewall of the partition ring 33.

[0060] In some embodiments of this invention, the inner wall of the baffle ring 33 has a multi-level stepped structure and / or the outer wall of the body part 42 has a multi-level stepped structure, so that a tortuous gap flow channel is formed between the inner wall of the baffle ring 33 and the outer wall of the body part 42. When the purging gas flows outward from the center of the gas flow channel 2 under the centrifugal force generated by the flow guiding structure 7, the stepped structure mainly plays a guiding role, guiding the gas to smoothly turn step by step and flow to the edge, with very little obstruction to active purging. When there is no purging or the pressure reverses, the tortuous gap flow channel prevents process gas or particles attempting reverse permeation from passing through in a straight line, requiring them to undergo multiple turns, collisions, and decelerations, which greatly extends the permeation path and effectively prevents process gas backflow. The tortuous gap flow channel plays the role of mechanical seal, and together with the centrifugal air curtain, it forms a dual and bidirectional protection system of "active purging (dynamic) plus labyrinth barrier (static)," which improves the isolation reliability and can more effectively prevent process gas from entering the protective cover 3 through the through hole 32 from the gas flow channel 2 and contacting and corroding the heater 1, significantly extending the service life of the heater 1 and reducing the maintenance frequency and cost.

[0061] In some embodiments of this utility model, the multi-level stepped structure includes at least two steps, and the transition surface between adjacent steps is a vertical surface or an inclined surface with an angle.

[0062] In some embodiments of this utility model, the protective cover 3 is a silicon carbide barrel or a graphite barrel coated with silicon carbide.

[0063] In some embodiments of this utility model, reference is made to Figure 1 and Figure 2 The bottom of the protective cover 3 is sealed and fixed on the bottom plate 8 of the chamber body.

[0064] Although the embodiments of this utility model 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 this utility model as described in the claims. Moreover, the utility model described herein may have other embodiments and can be implemented or realized in various ways.

Claims

1. A reaction chamber, characterized in that, It has the following features: heater; A protective cover is provided over the heater, the protective cover including opposing open ends and closed ends, the heater being located near the closed ends; A tray, located above the closed end, is used to support the substrate, and a gas flow channel communicating with the outside is formed between the tray and the closed end; A rotating shaft, with its top end extending movably through the closed end from the open end, is rotatably connected to the tray to drive the tray to rotate. The rotating shaft includes an outlet shaft section located within the gas flow channel, and the outlet shaft section has several outlet holes circumferentially open. A purge gas supply line is located inside the rotating shaft and communicates with each of the gas outlets to deliver purge gas to the gas flow channel.

2. The reaction chamber according to claim 1, characterized in that, Also includes: Several flow guiding structures are provided on the structure enclosed by the bottom surface of the tray and the closed end to further enhance the barrier effect on process gases.

3. The reaction chamber according to claim 2, characterized in that, The bottom of the tray is provided with a shaft connection part for connecting with the top end of the rotating shaft; a plurality of flow guiding structures are radially arranged around the shaft connection part on the bottom surface of the tray, and each flow guiding structure extends toward the outer edge of the tray.

4. The reaction chamber according to claim 2, characterized in that, The flow guiding structure is a rib structure or a groove structure.

5. The reaction chamber according to claim 4, characterized in that, The top surface of the tray is provided with a plurality of bearing grooves for bearing the substrate; the number of intersections between the orthographic projection of the rib structure on the top surface of the tray and each of the bearing grooves is 0.

6. The reaction chamber according to claim 3, characterized in that, The flow guiding structure is straight or curved in the radial direction.

7. The reaction chamber according to claim 1, characterized in that, A baffle ring is provided around the edge of the closed end, and the baffle ring, the tray, and the closed end form the gas flow channel; The tray includes a body portion, the top of which has an extension portion extending radially, and the bottom of which protrudes toward the closed end, the extension portion shielding the partition ring.

8. The reaction chamber according to claim 7, characterized in that, The inner wall of the partition ring has a multi-level stepped structure and / or the outer wall of the body has a multi-level stepped structure, so that a tortuous gap flow channel is formed between the inner wall of the partition ring and the outer wall of the body.

9. The reaction chamber according to claim 1, characterized in that, The distance h between the bottom of the tray and the top of the protective cover and the diameter D of the vent hole satisfy the following condition: 1 / 2h ≤ D ≤ h.

10. The reaction chamber according to claim 1, characterized in that, The number of air vents is greater than or equal to 6 and less than or equal to 16.

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