Cover body and polycrystalline silicon reduction furnace
By designing a special fin structure inside the polycrystalline silicon reduction furnace, the problems of eddy currents and dead zones in the reaction gas within the furnace were solved, achieving uniform gas distribution between the furnace wall and the silicon core, thus improving the uniformity of polycrystalline silicon deposition and production efficiency.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-08
- Publication Date
- 2026-03-06
AI Technical Summary
In existing polysilicon production processes, the flow path of reactive gases within the reduction furnace is complex, easily forming local eddies or dead zones, resulting in uneven temperature distribution and affecting the uniformity and quality of polysilicon deposition.
A special fin structure is designed inside the reduction furnace shroud. The fins are installed around the circumference of the shroud to form a uniform flow field. The shroud is then fastened to a chassis equipped with silicon cores to ensure that the gas is evenly distributed between the furnace wall and the silicon cores.
It improved the temperature distribution inside the furnace, enhanced the uniformity and quality of polysilicon deposition, and increased production efficiency.
Smart Images
Figure CN223973879U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of polysilicon production equipment, and more particularly to a polysilicon reduction furnace. Background Technology
[0002] In the polysilicon production process, the reduction furnace is one of the key pieces of equipment. The reduction furnace uses chemical vapor deposition (CVD) to decompose reactive gases (such as SiHCl3 and H2) at high temperatures, generating polysilicon which is then deposited on the surface of the silicon core. However, existing technologies have the following problems: after the reactive gases enter the furnace, their flow paths are complex, easily forming localized eddies or dead zones, resulting in uneven flow field distribution and consequently uneven temperature distribution within the furnace, affecting the uniformity and quality of polysilicon deposition. Furthermore, uneven temperature can lead to excessively fast or slow deposition rates in some areas, reducing overall production efficiency. Utility Model Content
[0003] To address the aforementioned problems, this application provides a cover comprising:
[0004] The cover body is provided with a material inlet and a material outlet; the cover body is divided into multiple first installation areas along its axial direction.
[0005] The fins are installed circumferentially in a first mounting area along the body of the cover, with each first mounting area having a set of fins; each fin is obliquely downward and has an angle of 30 to 90° with the inner wall of the body of the cover below it; the circumferential angle between multiple fins in each first mounting area is 15 to 30°.
[0006] Furthermore, the axial spacing between two adjacent fin groups is 0.2 to 0.35 times the height of the hood body.
[0007] Furthermore, the fin assembly at the bottom layer is spaced from the bottom of the shroud body by 0.25 to 0.4 times the height of the shroud body.
[0008] Furthermore, the shape of the fin is any one of a straight plate, a trapezoidal plate, or a corrugated plate.
[0009] Furthermore, when the fins are in the shape of straight plates, the length of each fin is 0.02 to 0.04 times the diameter of the shroud body, the width is 0.01 to 0.02 times the diameter of the shroud body, and the thickness is 0.002 to 0.004 times the diameter of the shroud body.
[0010] Furthermore, the fins are installed on the inner wall of the cover body by welding or bolting.
[0011] This application also provides a polycrystalline silicon reduction furnace, which includes:
[0012] The aforementioned cover is equipped with a cooling water jacket;
[0013] The chassis has a cooling water jacket, and a silicon core is installed on the chassis. The cover body is fastened to the chassis to form a furnace structure that houses the silicon core.
[0014] Furthermore, the top surface of the chassis is divided into multiple second mounting areas in a radial direction outward from the center of the chassis; multiple electrode units are evenly spaced along the circumference of each second mounting area on the chassis for mounting the silicon core.
[0015] Furthermore, each electrode unit includes two electrodes, which are respectively mounted on both ends of a silicon core.
[0016] Furthermore, each second installation area is a square strip area or a circular strip area.
[0017] Compared with the prior art, the beneficial effects of this utility model are:
[0018] By designing special fins inside the furnace enclosure, the reaction gas entering the enclosure is less likely to form eddies or dead zones. Furthermore, by fastening the enclosure to the chassis equipped with silicon cores, the gas entering the furnace can be distributed into a uniform flow field between the furnace wall and the silicon cores, which improves the temperature distribution inside the furnace and enhances the uniformity, quality, and deposition efficiency of polycrystalline silicon deposition. Attached Figure Description
[0019] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0020] Figure 1 This is a schematic diagram of a cover structure according to an embodiment of this application;
[0021] Figure 2 This is a bottom view of a cover according to an embodiment of this application;
[0022] Figure 3 This is a schematic cross-sectional view along the A-A' direction of a polycrystalline silicon reduction furnace according to an embodiment of this application;
[0023] Figure 4 This is a top view of the chassis of a polycrystalline silicon reduction furnace according to an embodiment of this application.
[0024] Figure label:
[0025] 10. Cover; 11. Gas inlet; 12. Gas outlet; 13. Fins;
[0026] 20. Chassis;
[0027] 30. Electrode unit; 31. Silicon core. Detailed Implementation
[0028] In the following description, only certain exemplary embodiments are briefly described. As those skilled in the art will recognize, the described embodiments can be modified in various ways without departing from the spirit or scope of this invention. Therefore, the drawings and description are considered exemplary in nature and not restrictive.
[0029] In the description of this utility model, it should be understood that the terms "length", "width", "thickness", "upper", "lower", "top", "bottom", "inner", "outer", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this utility model is in use, or the orientation or positional relationship commonly understood by those skilled in the art. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.
[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.
[0031] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.
[0033] The following disclosure provides many different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the present invention. Furthermore, reference numerals may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments discussed. In addition, examples of various specific processes and materials are provided in the present invention, but those skilled in the art will recognize the application of other processes and / or the use of other materials.
[0034] The embodiments of this utility model will now be described in detail with reference to the accompanying drawings.
[0035] Example 1
[0036] This utility model embodiment provides a cover 10, please refer to... Figures 1-2 .
[0037] The cover 10 is equipped with a cooling water jacket, and has a gas inlet 11 near its bottom end and a gas outlet 12 near its top end. The gas inlet 11 is equipped with a nozzle structure. The cover 10 is divided into multiple first installation areas along its axial direction. Multiple fins 13 are distributed circumferentially along the inner wall of the cover 10 within each first installation area. The fins 13 in each first installation area form a group. The axial spacing between two adjacent fin groups is 0.2 to 0.35 times the height of the cover. The spacing between the bottom fin group and the bottom end of the cover is 0.25 to 0.4 times the height of the cover. The circumferential angle α between the multiple fins 13 in each fin group is 15 to 30°.
[0038] Preferably, taking a cover height of 5 meters as an example, the cover 10 is divided into three first installation areas along its axial direction, with a distance of 1 meter between two adjacent fin groups, a distance of 1 meter between the bottom fin group and the bottom of the cover, and a distance of 100 mm between two adjacent fins in the fin group.
[0039] Each fin 13 is made of a high-temperature and corrosion-resistant material, such as stainless steel or nickel-based alloy. The fins 13 are fixed to the inner wall by welding or bolting to ensure installation stability. The shape of the fins 13 can be any one of a straight plate, trapezoidal plate, or corrugated plate. Each fin 13 is angled downwards, with an angle β of 30° to 90° between it and the inner wall of the cover below it. Taking a straight plate shape as an example, the length of each fin 13 is 0.02 to 0.04 times the diameter of the cover 10, the width is 0.01 to 0.02 times the diameter of the cover 10, and the thickness is 0.002 to 0.004 times the diameter of the cover 10.
[0040] Preferably, taking a shroud diameter of 3 meters as an example, the fins are 100 mm long, 5 mm thick, and 50 mm wide.
[0041] Based on this, when the reactive gas is injected into the shroud 10 through the gas inlet 11, the fins 13 have a turbulent effect on the gas field inside the shroud 10, thus avoiding the occurrence of local eddies or dead zones in the flow field.
[0042] Example 2
[0043] This application provides a polycrystalline silicon reduction furnace; please refer to [reference needed]. Figures 3-4 The polysilicon reduction furnace includes the enclosure 10 and the chassis 20 as described in Example 1;
[0044] The chassis 20 is equipped with a cooling water jacket and is connected to the bottom of the cover. In other words, by fastening the cover 10 onto the chassis, a furnace structure with an internal cavity can be formed, allowing the silicon core 30 to be placed upright in the cavity.
[0045] In the area on the top surface of the chassis 20 covered by the aforementioned receiving cavity, multiple second mounting areas are sequentially divided radially outward from the center of the chassis 20. Each second mounting area is a square or circular strip area. Multiple electrode units 30 are evenly spaced along the circumference of each second mounting area on the chassis 20. Each electrode unit 30 includes two electrodes, which are respectively mounted on both ends of a silicon core 31.
[0046] Based on this, the silicon core 31 is assembled on the chassis 20, and the cover 10 is assembled on the chassis 20. The reaction gas is injected into the space between the furnace wall and the silicon core 31 through the gas inlet 11. The airflow is disturbed by the fins 13 designed above to form a uniform flow field, so that the temperature distribution inside the furnace is uniform, which improves the uniformity and quality of polycrystalline silicon deposition, while also improving the deposition efficiency.
[0047] Based on the above embodiments, the working principle of this application is as follows:
[0048] The corresponding silicon core 31 is assembled at the electrode unit 30 of the chassis 20, and the cover 10 is assembled on the chassis 20. The reaction gas is injected into the space between the furnace wall and the silicon core 31 through the gas inlet 11. The resulting flow field becomes uniformly distributed under the disturbance of the fins 13.
[0049] Based on the above embodiments, the advantages of this application are:
[0050] By designing special fins 13 inside the enclosure 10 of the reduction furnace, the reaction gas entering the enclosure 10 is less likely to form eddies or dead zones. Furthermore, by fastening the enclosure 10 to the chassis 20 equipped with the silicon core 31, the gas entering the reduction furnace can be distributed into a uniform flow field between the furnace wall and the silicon core 31, which improves the temperature distribution inside the furnace and enhances the uniformity, quality, and deposition efficiency of polycrystalline silicon deposition.
Claims
1. A cover characterized by, It includes: The cover body is provided with a feeding port and a discharging port; The cover body is divided into a plurality of first mounting areas along its axial direction; The fins are installed on a first mounting area along the circumferential direction of the cover body, and the fins provided on each first mounting area form a group; each fin is inclined downward and is provided at an angle of 30-90° with the inner wall of the cover body below it; the circumferential angle between the fins in each first mounting area is 15-30°.
2. The enclosure of claim 1, wherein: The spacing between two adjacent fin groups in the axial direction of the cover body is 0.2-0.35 times the height of the cover body.
3. The enclosure of claim 2, wherein: The spacing between the bottommost fin group and the bottom end of the cover body is 0.25-0.4 times the height of the cover body.
4. The enclosure of claim 3, wherein: The shape of the fin is any one of a straight plate, a trapezoidal plate or a corrugated plate.
5. The enclosure of claim 4, wherein: When the shape of the fin is a straight plate, the length of each fin is 0.02-0.04 times the diameter of the cover body, the width is 0.01-0.02 times the diameter of the cover body, and the thickness is 0.002-0.004 times the diameter of the cover body.
6. The enclosure of claim 5, wherein: The fin is installed on the inner wall of the cover body by welding or bolt connection.
7. A polycrystalline silicon reduction furnace, characterized by It includes: The cover body of any one of claims 1-6 with a cooling water jacket; A base plate with a cooling water jacket, the base plate is provided with a silicon core, and the cover body is buckled on the base plate to form a furnace structure containing the silicon core.
8. The polysilicon reduction furnace of claim 7, wherein: The top surface area of the base plate is divided into a plurality of second mounting areas along the radial direction of the base plate from the center of the base plate; a plurality of electrode units are uniformly spaced along the circumferential direction of each second mounting area on the base plate for mounting the silicon core.
9. The polycrystalline silicon reduction furnace of claim 8, wherein: Each electrode unit includes two electrodes, and each electrode is provided with one end of a silicon core.
10. The polycrystalline silicon reduction furnace of claim 9, wherein: Each second mounting area is a square area or a circular area.