Gas guide cylinder for exhaust pipeline of single crystal furnace

Abstract

The utility model provides a gas guide cylinder for an exhaust pipeline of a single crystal furnace, and relates to the field of single crystal furnace production. The exhaust duct gas guide cylinder of the single crystal furnace comprises a cylinder body, a gas guide pipe and a gas guide pipe, the reducing structure comprises a reducing structure body, the reducing structure body extends in the circumferential direction of the inner wall of the barrel, and the reducing structure body is at least provided with a wave crest part, a wave crest part and a wave crest part, and the wave crest part protrudes in the direction of the central axis of the barrel; the wave trough parts are sunken in the direction away from the central axis of the cylinder body, and the wave trough parts and the wave crest parts are alternately arranged; according to the utility model, argon and other gases in the single crystal furnace are guided into the exhaust pipeline to be exhausted, the heat loss can be reduced, and oxide blockage is not easy to generate.

Description

Technical Field

[0001] The utility model relates to the field of single crystal furnace production, and particularly to a gas guide cylinder for an exhaust pipeline of a single crystal furnace. Background Art

[0002] The Czochralski process, also known as the direct pulling method, abbreviated as the CZ method, is a crystal growth method used to obtain semiconductors (such as silicon, germanium, and gallium arsenide, etc.), metals (such as palladium, platinum, silver, gold, etc.), salts, and synthetic gemstones. In the single crystal furnace using the CZ method, argon gas enters the single crystal furnace from the auxiliary chamber or the main chamber through the argon gas control system, passes through the crystal rod and the thermal field, and finally is discharged from the exhaust pipeline at the bottom of the furnace.

[0003] A gas guide cylinder can be installed in the existing exhaust pipeline, and the gas can flow into the exhaust pipeline through the gas guide cylinder and be discharged. However, the heat and oxides in the thermal field are also discharged along with the gas. During the design, the diameter of the gas guide cylinder can be adjusted to adjust the discharged heat and oxides. When the diameter of the gas guide cylinder is reduced, the heat discharged from the thermal field will also decrease, which is beneficial to reducing the power input of the heater and achieving the effect of energy consumption reduction. However, oxides are likely to accumulate at the gas guide cylinder, resulting in blockage after long-term operation. Therefore, the diameter of the existing gas guide cylinder is usually designed to be larger to avoid blockage, but this also increases heat loss and causes energy waste. Summary of the Utility Model

[0004] The utility model provides a gas guide cylinder for an exhaust pipeline of a single crystal furnace with reduced heat loss and not prone to oxide blockage, while avoiding oxides from starting to accumulate on the cylinder wall and causing blockage, and solving the problem of large diameter of the gas guide cylinder in the prior art, more heat loss in the gas, and energy waste.

[0005] The technical solution adopted by the utility model is as follows:

[0006] A gas guide cylinder for an exhaust pipeline of a single crystal furnace, comprising:

[0007] A cylinder body, on the inner wall of which a variable diameter structure is provided;

[0008] Wherein, the variable diameter structure includes a variable diameter structure body, the variable diameter structure body extends circumferentially along the inner wall of the cylinder body, and the variable diameter structure body at least has:

[0009] A wave crest part, protruding towards the central axis direction of the cylinder body; and

[0010] A wave trough part, recessed away from the central axis direction of the cylinder body and arranged alternately with the wave crest part.

[0011] Further, the wave crest part is in an arc-shaped protruding shape, and the wave trough part is in an arc-shaped recessed shape.

[0012] Further, the radius of curvature of the peak portion is equal to that of the trough portion.

[0013] Further, the peak portion is symmetric about the radial direction of the cylinder passing through its midpoint, and the trough portion is symmetric about the radial direction of the cylinder passing through its midpoint.

[0014] Further, the tangents at the junction of the peak portion and the trough portion coincide.

[0015] Further, the trough portion includes a first half-trough portion, which is arranged at the air inlet end of the cylinder, and the depression at the junction of the first half-trough portion and the air inlet end of the cylinder is the deepest.

[0016] Further, the trough portion includes a second half-trough portion, which is arranged at the air outlet end of the cylinder, and the depression at the junction of the second half-trough portion and the air outlet end of the cylinder is the deepest.

[0017] Further, it further includes: an air guide cover, which is arranged at the air inlet end of the cylinder, and the air guide cover at least has:

[0018] a communication hole, which is arranged at one end where the air guide cover is connected to the cylinder; and

[0019] a plurality of air inlets, which are arranged on the side wall of the air guide cover.

[0020] Further, an annular groove is arranged at the air inlet end of the cylinder, a convex ring surrounding the communication hole is arranged on the air guide cover, and the convex ring is adapted to the annular groove.

[0021] Further, the shape and size of the communication hole are adapted to the opening at the air inlet end of the cylinder.

[0022] The beneficial effects of the present utility model are as follows:

[0023] 1. By arranging the peak portion, the present utility model reduces the local cross-sectional area inside the cylinder, reduces the exhaust diameter of the air guide cylinder, thereby reducing heat loss; at the same time, by arranging the trough portion, a cylinder wall with a changing diameter is formed in cooperation with the peak portion. When the exhaust diameter of the air guide cylinder becomes smaller, the air flow passes through the alternately narrowing and expanding inner wall to increase the air flow velocity, thereby strengthening the impact force on the oxide, reducing the adhesion amount of the oxide, reducing the blockage of impurities such as oxide particles, and thus avoiding the aggregation of oxides starting from the cylinder wall to cause blockage, while solving the problems in the prior art that the diameter of the air guide cylinder is large, and more heat is lost in the gas, resulting in energy waste. Description of the Drawings

[0024] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0025] Figure 1 Isometric perspective view of the air guide cylinder according to the embodiment of the present utility model;

[0026] Figure 2 Internal structure schematic diagram of the air guide cylinder according to the embodiment of the present utility model;

[0027] Figure 3 Is Figure 2 Enlarged view of part A in

[0028] Figure 4 Isometric schematic diagram of the air guide cover according to the second embodiment of the present utility model;

[0029] Figure 5 Internal structure schematic diagram of the air guide cylinder according to the second embodiment of the present utility model.

[0030] Reference numerals:

[0031] 100 - Cylinder body, 120 - Crest part, 140 - Trough part, 142 - First half - trough part, 144 - Second half - trough part, 150 - Annular groove, 160 - First annular outer flange;

[0032] 200 - Air guide cover, 201 - Communication hole, 203 - Air inlet, 250 - Convex ring, 260 - Second annular outer flange;

[0033] D1 - Minimum inner diameter; D2 - Maximum inner diameter; D3 - Outer diameter; L - Length; R1 - First radius of curvature; R2 - Second radius of curvature; R3 - Third radius of curvature; R4 - Fourth radius of curvature. Detailed implementation manners

[0034] In the description of the present utility model, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0035] The following disclosure provides many different embodiments or examples for implementing different structures of the present utility model. To simplify the disclosure of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present utility model.

[0036] The embodiments of the utility model will be described in detail below with reference to the accompanying drawings.

[0037] Embodiment 1

[0038] Please refer to Figures 1-3 , this embodiment provides a gas guiding cylinder for the exhaust pipeline of a single crystal furnace, which is installed at the bottom of the single crystal furnace. Its intake end is located above the thermal field at the bottom of the single crystal furnace, and its outlet end extends into the exhaust pipeline, used to guide gases such as argon in the single crystal furnace into the exhaust pipeline for discharge, and can reduce heat loss and is not prone to oxide blockage, such as blockage by silicon monoxide and dust impurities. The gas guiding cylinder for the exhaust pipeline of the single crystal furnace mainly includes: a cylinder body 100, etc.

[0039] As Figure 1 , Figure 2 shown in, the cylinder body 100 is a cylinder-shaped cylinder body, which is the main gas guiding structure of the gas guiding cylinder for the exhaust pipeline of the single crystal furnace in this embodiment. And, compared with the straight wall structure more commonly used in the inner wall of the existing gas guiding cylinder, a variable diameter structure is provided on the inner wall of the cylinder body 100 in this embodiment. Among them, the variable diameter structure includes a variable diameter structure body, and the variable diameter structure body extends circumferentially along the inner wall of the cylinder body 100, passing through a circular extension trajectory to form an annular variable diameter structure, and its cross-sections in different radial directions are the same, maintaining the uniformity of the gas flow velocity in different radial directions inside the gas guiding cylinder.

[0040] The variable diameter structure body mainly has a wave crest part 120 and a wave trough part 140, and the wave trough part 140 and the wave crest part 120 are arranged alternately. Among them, three wave crest parts 120 protrude towards the central axis direction of the cylinder body 100, used to reduce the local inner diameter of the cylinder body 100 and narrow the exhaust diameter of the gas guiding cylinder. At the highest point of the wave crest part 120, the minimum inner diameter D1 of the cylinder body 100 is 110 mm. Four wave trough parts 140 are recessed away from the central axis direction of the cylinder body 100, used to cooperate with the wave crest part 120 to form a cylinder wall with a variable diameter. At the deepest part of the wave trough part 140, the maximum inner diameter D2 of the cylinder body 100 is 130 mm. At the same time, the outer diameter D3 of the cylinder body 100 is 176 mm, and the length L is 350 mm.

[0041] In this embodiment, by providing the crest portion 120 in the gas guide cylinder of the exhaust pipeline of the single crystal furnace, the local cross-sectional area inside the cylinder body 100 is reduced, the exhaust diameter of the gas guide cylinder is narrowed, thereby reducing heat loss. At the same time, the trough portion 140 is provided, which cooperates with the crest portion 120 to form a cylinder wall with a changing diameter. When the exhaust diameter of the gas guide cylinder becomes smaller, the air flow passes through the alternately narrowing and expanding inner wall to increase the air flow velocity, thereby strengthening the impact force on the oxide, reducing the adhesion amount of the oxide, and reducing the blockage of impurities such as oxide particles. Thus, while avoiding the accumulation of oxides starting from the cylinder wall and causing blockage, the problem in the prior art that the diameter of the gas guide cylinder is large and a large amount of heat is lost in the gas, resulting in energy waste, is solved.

[0042] Meanwhile, in this embodiment, the crest portion 120 is in an arc-shaped convex shape; the trough portion 140 is in an arc-shaped concave shape. On the one hand, the arc shape can reduce the adhesion stability of the oxide on the inner wall of the cylinder body 100. At the same time, the arc shape can avoid the existence of sharp points or edges and corners in the shape of the protrusion or depression, resulting in large fluctuations in the air flow velocity near the inner wall of the cylinder body 100, thereby avoiding the accumulation of oxides caused by the reduction of the gas flow velocity at local positions on the crest portion 120 and the trough portion 140.

[0043] Furthermore, in this embodiment, the first curvature radius R1 and the second curvature radius R2 of the crest portion 120 and the trough portion 140 are designed to be equal, both being 82.4 mm, to avoid large fluctuations in the air flow velocity at the junction of the adjacent crest portion 120 and trough portion 140 due to the difference in the curvature radii, thereby avoiding the accumulation of oxides caused by the reduction of the gas flow velocity at the junction of the crest portion 120 and the trough portion 140. As Figure 3 shown, the crest portion 120 is symmetric about the radial direction of the cylinder body 100 passing through its midpoint; the trough portion 140 is symmetric about the radial direction of the cylinder body 100 passing through its midpoint, so that the curvature radii on both sides of the crest portion 120 and the trough portion 140 are equal, to avoid large fluctuations in the air flow velocity near the crest portion 120 and the trough portion 140, thereby avoiding the accumulation of oxides caused by the reduction of the gas flow velocity at local positions on the crest portion 120 and the trough portion 140. And, the tangents at the junction of the crest portion 120 and the trough portion 140 coincide, to avoid the generation of edges and corners at the junction of the adjacent crest portion 120 and trough portion 140, resulting in large fluctuations in the air flow velocity, thereby avoiding the accumulation of oxides caused by the reduction of the gas flow velocity at the junction of the crest portion 120 and the trough portion 140.

[0044] In addition, the trough portion 140 of this embodiment further includes a first half-trough portion 142 and a second half-trough portion 144 at both ends of the cylinder 100. The shapes of the first half-trough portion 142 and the second half-trough portion 144 are different from those of the other trough portions 140 in the middle of the cylinder 100, but are approximately the same as the half-side shapes of the other trough portions 140. However, the third curvature radius R3 and the fourth curvature radius R4 of both the first half-trough portion 142 and the second half-trough portion 144 are 80 mm. Among them, the first half-trough portion 142 is arranged at the air inlet end of the cylinder 100, and the junction of the first half-trough portion 142 and the air inlet end of the cylinder 100 is the deepest recess. The first half-trough portion 142 widens the aperture at the air inlet end of the cylinder 100, making it easier for the air flow to pass through, reducing the gas flow to the surrounding heat field, and avoiding the corrosion of nearby heat field components by the corrosive components in the gas. The second half-trough portion 144 is arranged at the air outlet end of the cylinder 100, and the junction of the second half-trough portion 144 and the air outlet end of the cylinder 100 is the deepest recess. The first half-trough portion 142 widens the aperture at the air outlet end of the cylinder 100, which is used to avoid large fluctuations in the air flow velocity at the air outlet end, thereby avoiding the accumulation of oxides after the air flow velocity decreases at the air outlet end.

[0045] Embodiment 2

[0046] The second embodiment proposes another gas guide cylinder for the exhaust pipe of a single crystal furnace, and a gas guide cover 200 is further added on the basis of the above embodiment.

[0047] Please refer to Figures 4-5 , the gas guide cover 200 in the second embodiment is generally in a cylindrical shape and is hollow inside for passing air flow. The gas guide cover 200 is arranged at the air inlet end of the cylinder 100, and the gas guide cover 200 has at least one communication hole 201 and a plurality of air inlets 203. In this embodiment, one communication hole 201 is circular and is arranged at the end where the gas guide cover 200 is connected to the cylinder 100; four air inlets 203 are generally rectangular and are arranged on the side wall of the gas guide cover 200. By arranging the gas guide cover 200, it can prevent the high-temperature silicon material generated during the silicon melting process from entering the exhaust pipe through the gas guide cylinder and avoid damaging the exhaust pipe; at the same time, it can increase the air flow velocity at the air inlet end of the cylinder 100 and increase the impact force of the gas on the inner wall of the cylinder 100, thereby reducing the oxides attached to the inner wall of the cylinder 100, reducing the possibility of blockage, and being beneficial to realizing long-term operation.

[0048] Moreover, in this embodiment, an annular groove 150 is provided at the air inlet end of the cylinder body 100, and a convex ring 250 surrounding the communication hole 201 is provided on the air guide cover 200. The convex ring 250 is adapted to the annular groove 150. The insertion of the convex ring 250 into the annular groove 150 can connect the cylinder body 100 and the air guide cover 200. By providing the annular groove 150 and the convex ring 250, a detachable connection between the cylinder body 100 and the air guide cover 200 is formed, which facilitates the regular removal of the air guide cover 200 for cleaning the connection between the cylinder body 100 and the air guide cover 200. Further, a first annular outer flange 160 is provided at the air inlet end of the cylinder body 100, and a second annular outer flange 260 is provided at one end of the air guide cover 200 connected to the cylinder body 100. The second annular outer flange 260 is adapted to the first annular outer flange 160 in terms of size and shape. The cooperation of the two can improve the connection stability between the air guide cover 200 and the cylinder body 100, reduce the concentration of extrusion force at the connection, reduce stress accumulation, and extend the service life of the air guide cylinder.

[0049] Meanwhile, in this embodiment, the shape and size of the communication hole 201 are adapted to the opening of the air inlet end of the cylinder body 100. Since the inner diameter of the cylinder body 100 is expanded in the above embodiment, the size of the communication hole 201 in this embodiment is also expanded, so as to increase the flow rate of the hot field air flow directly flowing into the cylinder body 100, accelerate the exhaust speed, and reduce the corrosion of oxides in the gas to nearby hot field components (such as bottom heaters).

[0050] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. The above embodiments and the descriptions in the specification are only preferred examples of the present invention and do not limit the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of protection claimed by the present invention is defined by the appended claims and their equivalents.

Claims

1. A gas guide tube for an exhaust duct of a single crystal furnace, characterized in that: Include: The cylinder (100) has a diameter-changing structure disposed on its inner wall; The variable diameter structure comprises a variable diameter structure body, the variable diameter structure body extends circumferentially along the inner wall of the cylinder (100), and the variable diameter structure body has at least: The crest portion (120) protrudes toward the central axis of the cylinder (100); and The trough portion (140) is recessed away from the central axis direction of the cylinder (100), and is arranged alternately with the peak portion (120).

2. The single crystal furnace exhaust duct gas guide tube according to claim 1, characterized in that: The crest portion (120) is in an arc-shaped convex shape, and the trough portion (140) is in an arc-shaped concave shape.

3. The single crystal furnace exhaust duct gas guide tube according to claim 2, characterized in that: The curvature radii of the crest portion (120) and the trough portion (140) are equal.

4. The single crystal furnace exhaust duct gas guide tube according to claim 2, characterized in that: The wave crest portion (120) is symmetrical on both sides with the radial direction of the cylinder (100) passing through the midpoint thereof as an axis, and the wave trough portion (140) is symmetrical on both sides with the radial direction of the cylinder (100) passing through the midpoint thereof as an axis.

5. The single crystal furnace exhaust duct gas guide tube according to claim 2, characterized in that: The tangent line at the junction of the crest portion (120) and the trough portion (140) coincides.

6. The single crystal furnace exhaust duct gas guide tube according to claim 1, characterized in that: The trough portion (140) comprises a first half trough portion (142), the first half trough portion (142) being arranged at the air inlet end of the cylinder (100), and the first half trough portion (142) is most deeply recessed at the junction with the air inlet end of the cylinder (100).

7. The single crystal furnace exhaust duct gas guide tube according to claim 1, characterized in that: The trough portion (140) comprises a second half trough portion (144), the second half trough portion (144) being arranged at the gas outlet end of the cylinder (100), and the junction between the second half trough portion (144) and the gas outlet end of the cylinder (100) is the deepest.

8. The single crystal furnace exhaust duct gas guide tube according to any one of claims 1 to 7, characterized in that: It also comprises: an air guide cover (200), the air guide cover (200) being arranged at the air inlet end of the cylinder (100), the air guide cover (200) having at least: a communication hole (201), arranged at one end where the air guide cover (200) is connected to the cylinder (100); and A plurality of air inlets (203) are arranged on the side wall of the air guide cover (200).

9. The single crystal furnace exhaust duct gas guide tube according to claim 8, characterized in that: An annular groove (150) is provided on the air inlet end of the cylinder (100), and a convex ring (250) surrounding the communication hole (201) is provided on the air guide cover (200), and the convex ring (250) is adapted to fit the annular groove (150).

10. The single crystal furnace exhaust duct gas guide tube according to claim 8, characterized in that: The communicating hole (201) is adapted in shape and size to the opening of the air inlet end of the cylinder (100).

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