A protective disc tablet for a single crystal furnace

Abstract

The utility model belongs to single crystal furnace equipment technical field, concretely speaking is a kind of for the single crystal furnace's guard disc tablet press, including multiple tablet press body, multiple tablet press body are all set to fan shape, and constitute a circular;The arc small end of tablet press body is all set with first installation slot;The arc big end of tablet press body is all set with second installation slot;First fixed sleeve is installed in the first installation slot;By setting multiple fan-shaped tablet press body, tablet press body head-to-tail connection constitutes circular tablet press, arc surface constitutes complete circumference, guard disc tablet press is placed in the inside of lower heat preservation cylinder, is placed in the upper end of pressing felt layer, for protecting heat preservation pressing felt layer from being damaged guard disc tablet press, and prevent warping under the action of external force, by setting first fixed sleeve and second fixed sleeve, the both ends of tablet press body are pressed tightly fixed, prevent warping, to realize the splicing piece of partially replaceable damaged tablet press body, need not overall replacement, reduce maintenance cost.

Description

Technical Field

[0001] This utility model belongs to the technical field of single crystal furnace equipment, specifically a protective plate pressing device for single crystal furnaces. Background Technology

[0002] A single crystal furnace is a device that melts polycrystalline materials such as polycrystalline silicon in an inert gas environment using a graphite heater, and grows dislocation-free single crystal silicon using the Czochralski method. Inside the single crystal furnace, the thermal field mainly consists of a set of components including a flow guide tube, various graphite parts, heaters, furnace bottom protective plates and pressure plates, and insulation materials. The protective plates and pressure plates are placed inside the lower insulation cylinder, above the pressure plate felt layer, to protect the insulation pressure plate felt layer from damage.

[0003] A Chinese patent with publication number CN223255520U discloses an integrated protective plate pressing sheet for a single crystal furnace. The sheet includes an integrated protective plate pressing sheet body, with a first reinforcing rib and a second reinforcing rib perpendicular to each other at its bottom. This invention reduces the contact area between the protective plate pressing sheet and the insulating felt, thus reducing heat loss. Simultaneously, the integrated structure eliminates gaps between the protective plate pressing sheet and joints, reducing the corrosive effects of furnace gases on the insulation material, extending its service life, and thereby lowering production costs.

[0004] In the current technology, the protective plate is set as an integral structure. Due to the influence of the crucible's own weight and the plastic deformation that easily occurs during the extrusion of the filler, wear may occur at the electrode sleeve hole. However, if any electrode sleeve hole is worn, the entire protective plate needs to be replaced.

[0005] Therefore, a protective plate pressing device for single crystal furnaces is proposed to address the above problems. Utility Model Content

[0006] To overcome the shortcomings of existing technologies and solve the problem of needing to replace the entire protective plate when any electrode sleeve hole is worn, a protective plate pressing method for single crystal furnaces is proposed.

[0007] The technical solution adopted by this utility model to solve its technical problem is as follows: The protective plate pressing sheet for a single crystal furnace of this utility model includes multiple pressing sheet bodies, each of which is fan-shaped and forms a circle; a first mounting groove is opened at the end of the pressing sheet body with a smaller arc; a second mounting groove is opened at the end of the pressing sheet body with a larger arc; a first fixing sleeve is fitted inside the first mounting groove; a second fixing sleeve is fitted inside the second mounting groove, and the outer wall of the second fixing sleeve is in contact with the inner wall of the single crystal furnace.

[0008] Preferably, the bottom of the tablet body is fixedly provided with a first reinforcing rib and two second reinforcing ribs, with the first reinforcing rib penetrating through the two second reinforcing ribs; the arc shape of the second reinforcing rib is the same as the arc shape of the tablet body.

[0009] Preferably, the center of the first fixing sleeve has a support rod through hole; two air guide holes are opened on the two symmetrical pressing bodies, and electrode sleeve holes are opened on the remaining pressing bodies.

[0010] Preferably, limiting grooves are provided on both side walls of the tablet body, and the two limiting grooves are respectively provided on the top and bottom of the tablet body, and the limiting grooves of two adjacent tablet bodies are engaged and inserted.

[0011] Preferably, a fiber Bragg grating sensor is embedded inside the tablet press body to detect abnormal vibrations of the tablet press body.

[0012] Preferably, a detection line is embedded in the first fixing sleeve, and the two ends of the detection line are respectively connected to the adjacent electrodes and linked with the detection circuit.

[0013] Preferably, the thickness of the first and second reinforcing ribs is 4-7 mm, the width is 6-10 mm, and the connection between them and the tablet body is formed by casting; both the first and second reinforcing ribs are made of carbon-carbon composite material.

[0014] Preferably, the thickness of the tablet body is 10-12 mm; the tablet body is made of high-purity graphite material and coated with a boron nitride ceramic coating, the thickness of which is 50-100 micrometers.

[0015] The beneficial effects of this utility model are: This utility model provides a protective plate for a single crystal furnace. Multiple fan-shaped plate bodies are connected end-to-end to form a circular plate, with the arc surfaces forming a complete circumference. The protective plate is placed inside the lower insulation cylinder, above the pressure plate felt layer, to protect the insulation felt layer from damage and prevent warping under external force. A first and second fixing sleeve are used to press and fix both ends of the plate body, preventing warping. This allows for partial replacement of damaged plate bodies without requiring complete replacement, reducing maintenance costs.

[0016] This invention provides a protective plate pressing device for a single crystal furnace. It uses a fiber optic grating sensor to monitor abnormal vibrations and trigger an early warning. A detection line is installed inside the first fixed sleeve, with electrodes connected to both ends and linked to the detection circuit. When the detection line melts due to silicon molten material overflow, an alarm signal is triggered to provide timely warning of an accident. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the present invention and form part of this application, illustrate exemplary embodiments of the present invention and, together with the description thereof, serve to explain the present invention and do not constitute an undue limitation thereof. In the drawings: Figure 1 This is a perspective view of the present invention; Figure 2 This is a perspective view of the first and second reinforcing ribs in this utility model; Figure 3 This is a perspective view of the first mounting slot box and the second mounting slot in this utility model; Figure 4 This is a perspective view of the tablet body in this utility model; Figure 5 This is a cross-sectional view of the tablet body in this utility model; Legend: 1. Tablet body; 11. First fixing sleeve; 12. Second fixing sleeve; 13. Support rod through hole; 14. Gas guide through hole; 15. Electrode sheath hole; 16. Limiting groove; 17. First mounting groove; 18. Second mounting groove; 2. First reinforcing rib; 21. Second reinforcing rib; 3. Fiber optic grating sensor; 4. Detection line. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0019] Specific implementation examples are given below.

[0020] Please see Figures 1-5 This utility model provides a protective plate pressing device for a single crystal furnace, comprising multiple pressing bodies 1, each of which is fan-shaped and forms a circle; each pressing body 1 has a first mounting groove 17 at its smaller arc end; each pressing body 1 has a second mounting groove 18 at its larger arc end; a first fixing sleeve 11 is fitted inside the first mounting groove 17; a second fixing sleeve 12 is fitted inside the second mounting groove 18, and the outer wall of the second fixing sleeve 12 contacts the inner wall of the single crystal furnace.

[0021] In existing technologies, the protective plate pressing sheet is designed as a single unit. Due to the weight of the crucible and the plastic deformation that easily occurs during the extrusion of the filler, wear may occur at the electrode sleeve hole 15. However, if any electrode sleeve hole 15 is worn, the entire protective plate pressing sheet needs to be replaced. By setting multiple fan-shaped pressing sheet bodies 1, which are connected end to end to form a circular pressing sheet with arc surfaces forming a complete circumference, the protective plate pressing sheet is placed inside the lower insulation cylinder and above the pressure plate felt layer. This protects the insulation pressure plate felt layer from damage to the protective plate pressing sheet and prevents it from warping under external force. By setting the first fixing sleeve 11 and the second fixing sleeve 12, the two ends of the pressing sheet body 1 are pressed and fixed to prevent warping. This allows for the partial replacement of damaged pressing sheet body 1 splices without the need for complete replacement, thus reducing maintenance costs.

[0022] Furthermore, such as Figure 1 As shown, the bottom of the tablet body 1 is fixed with a first reinforcing rib 2 and two second reinforcing ribs 21, and the first reinforcing rib 2 passes through the two second reinforcing ribs 21; the arc shape of the second reinforcing rib 21 is the same as the arc shape of the tablet body 1.

[0023] During operation, the first reinforcing rib 2 and the second reinforcing rib 21 are in direct contact with the top of the insulation material. At the same time, the first reinforcing rib 2 and the second reinforcing rib 21 are evenly distributed at the bottom of the pressing body 1, and evenly bear the pressure brought by the pressing body 1 and the single crystal furnace above it, thereby increasing the mechanical strength of the pressing body 1 above the insulation material and extending the length of the pressing body 1. Meanwhile, the first reinforcing rib 2 and the second reinforcing rib 21 are in direct contact with the insulation material, which reduces the area of ​​the pressing body 1 in direct contact with the insulation material, thereby reducing heat loss and achieving reduced power consumption.

[0024] Furthermore, such as Figure 2 As shown, the first fixing sleeve 11 has a support rod through hole 13 in the center; two air guide holes 14 are opened on the two symmetrical pressing bodies 1, and electrode sheath holes 15 are opened on the remaining pressing bodies 1.

[0025] During operation, the support rod penetrates the circular protective plate formed by all the pressing bodies 1, forming a rigid spindle support; effectively suppressing the radial displacement or warping deformation of the protective plate caused by thermal expansion under high temperature environment, ensuring that the coaxiality error between the protective plate and the crucible is <0.5mm, and ensuring the stability of the crystal growth interface; two symmetrical gas guide holes 14 form a counter-flow gas inlet structure, forcibly forming a laminar flow gas barrier; preventing volatile impurities from diffusing upward to the seed crystal area; accelerating the discharge of desorbed gas from the melt surface, reducing the bubble defect rate; the electrode sheath hole 15 has a corundum tube or boron nitride ceramic sleeve built in, achieving triple protection.

[0026] Furthermore, such as Figure 4As shown, limiting grooves 16 are provided on both side walls of the tablet body 1, and the two limiting grooves 16 are respectively provided on the top and bottom of the tablet body 1, and the limiting grooves 16 of two adjacent tablet bodies 1 are inserted into each other.

[0027] During operation, the limiting grooves 16 of two adjacent pressing bodies 1 are connected end to end and interlocked to effectively suppress the creep deformation of graphite materials at high temperatures. Good sealing is crucial to prevent impurities from entering the molten silicon.

[0028] Furthermore, such as Figure 5 As shown, a fiber optic grating sensor 3 is embedded inside the tablet body 1 to detect abnormal vibrations of the tablet body 1.

[0029] During operation, the single crystal furnace is a high-temperature device used to grow semiconductor materials. Under high-temperature conditions, the materials may undergo thermal expansion or be subjected to mechanical stress, resulting in abnormal vibration, which in turn affects the crystal quality or even causes failure. The embedded fiber optic grating sensor 3 monitors abnormal vibration. If the abnormal vibration threshold is set to 5 Hz / g, an early warning will be triggered.

[0030] Furthermore, such as Figure 5 As shown, a detection line 4 is embedded in the first fixing sleeve 11. The two ends of the detection line 4 are respectively connected to the adjacent electrodes and are linked with the detection circuit.

[0031] During operation, a detection line 4 is installed inside the first fixed sleeve 11, with electrodes connected to both ends and linked to the detection circuit. When the overflow of silicon liquid causes the detection line 4 to melt and break, an alarm signal is triggered to provide timely warning of accidents.

[0032] Furthermore, such as Figure 2 As shown, the thickness of the first reinforcing rib 2 and the second reinforcing rib 21 is 4-7 mm, the width is 6-10 mm, and the connection between them and the tablet body 1 is formed by casting; both the first reinforcing rib 2 and the second reinforcing rib 21 are made of carbon-carbon composite material.

[0033] During operation, the temperature inside the single crystal furnace reaches over 1400℃, requiring materials with extremely high temperature resistance and thermal stability. Long-term exposure to corrosive media such as silicon vapor and molten metal impurities necessitates corrosion resistance. The protective plate must withstand combined loads including its own weight, thermal stress, and crystal growth tension, requiring a high-strength, lightweight structure. A carbon-carbon composite material is employed, possessing a high melting point, good thermal shock resistance, and low density, reducing weight while maintaining strength.

[0034] Furthermore, such as Figure 4As shown, the thickness of the tablet body 1 is 10-12 mm; the tablet body 1 is made of high-purity graphite material and is coated with a boron nitride ceramic coating, the thickness of which is 50-100 micrometers.

[0035] During operation, the thickness of the tablet body 1 is 10-12 mm, ensuring sufficient mechanical strength without being overly bulky. High-purity graphite is used, exhibiting excellent stability at high temperatures, resistance to oxidation, and good thermal conductivity. This is crucial for single-crystal furnaces, which require rapid heat dissipation to prevent damage from localized overheating. Furthermore, graphite's chemical inertness makes it suitable for handling corrosive environments such as silicon melts. The surface is coated with a boron nitride ceramic layer with a thickness between 50-100 micrometers. Boron nitride itself is a very hard and wear-resistant material with good corrosion resistance. The coating likely serves to further protect the graphite matrix from chemical erosion and mechanical wear, extending its service life.

[0036] Working principle: Multiple fan-shaped pressing bodies 1 are set up, and the pressing bodies 1 are connected end to end to form a circular pressing body. The arc surface forms a complete circumference. The protective pressing body is placed inside the lower insulation cylinder and on the upper end of the pressing plate felt layer. It is used to protect the insulation pressing plate felt layer from damage to the protective pressing body and to prevent the edge from warping under external force. By setting the first fixing sleeve 11 and the second fixing sleeve 12, the two ends of the pressing body 1 are pressed and fixed to prevent warping. Thus, the spliced ​​pieces of the damaged pressing body 1 can be replaced locally without replacing the whole body, reducing maintenance costs.

[0037] The first reinforcing rib 2 and the second reinforcing rib 21 are directly in contact with the top of the insulation material. At the same time, the first reinforcing rib 2 and the second reinforcing rib 21 are evenly distributed at the bottom of the pressing body 1, and evenly bear the pressure brought by the pressing body 1 and the single crystal furnace above it, thereby increasing the mechanical strength of the pressing body 1 above the insulation material and extending the length of the pressing body 1. At the same time, the first reinforcing rib 2 and the second reinforcing rib 21 are in direct contact with the insulation material, reducing the area of ​​the pressing body 1 in direct contact with the insulation material, reducing heat loss and achieving reduced power consumption.

[0038] The foregoing has shown and described the basic principles, main features, and advantages of this utility model. Those skilled in the art should understand that this utility model is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of this utility model. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model.

Claims

1. A protective plate pressing device for a single crystal furnace, characterized in that: The device includes multiple tablet pressing bodies (1), each of which is fan-shaped and forms a circle. Each tablet pressing body (1) has a first mounting groove (17) at the smaller arc end and a second mounting groove (18) at the larger arc end. A first fixing sleeve (11) is installed inside the first mounting groove (17) and a second fixing sleeve (12) is installed inside the second mounting groove (18). The outer wall of the second fixing sleeve (12) is in contact with the inner wall of the single crystal furnace.

2. The protective plate pressing device for a single crystal furnace according to claim 1, characterized in that: The bottom of the tablet body (1) is fixed with a first reinforcing rib (2) and two second reinforcing ribs (21), and the first reinforcing rib (2) passes through the two second reinforcing ribs (21); the arc shape of the second reinforcing rib (21) is the same as the arc shape of the tablet body (1).

3. The protective plate pressing device for a single crystal furnace according to claim 2, characterized in that: The first fixing sleeve (11) has a support rod through hole (13) in the center; two gas guide holes (14) are opened on the two symmetrical pressing bodies (1), and electrode sheath holes (15) are opened on the remaining pressing bodies (1).

4. A protective plate pressing device for a single crystal furnace according to claim 3, characterized in that: Limiting grooves (16) are provided on both side walls of the tablet body (1), and the two limiting grooves (16) are respectively located at the top and bottom of the tablet body (1), and the limiting grooves (16) of two adjacent tablet bodies (1) are connected in a cooperative manner.

5. A protective plate press for a single crystal furnace according to claim 4, characterized in that: The tablet body (1) is internally embedded with a fiber optic grating sensor (3) for detecting abnormal vibrations of the tablet body (1).

6. A protective plate pressing device for a single crystal furnace according to claim 5, characterized in that: The first fixing sleeve (11) is embedded with a detection line (4), the two ends of which are connected to the adjacent electrodes and linked with the detection circuit.

7. A protective plate press for a single crystal furnace according to claim 6, characterized in that: The thickness of the first reinforcing rib (2) and the second reinforcing rib (21) is 4-7 mm and the width is 6-10 mm. The connection between them and the tablet body (1) is formed by casting. Both the first reinforcing rib (2) and the second reinforcing rib (21) are made of carbon-carbon composite material.

8. A protective plate pressing device for a single crystal furnace according to claim 7, characterized in that: The thickness of the tablet body (1) is 10-12 mm; the tablet body (1) is made of high-purity graphite material and is coated with a boron nitride ceramic coating, the thickness of which is 50-100 micrometers.

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