Thermal insulation structure and single crystal furnace
By using a double-layer insulation structure design, combining an inner layer of isostatic graphite and an outer layer of carbon-carbon composite material, the problems of easy damage and low cleanliness of the insulation structure of the single crystal furnace are solved, thus improving the quality and insulation effect of single crystal silicon.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- ZHEJIANG AIKO SOLAR ENERGY TECH CO LTD
- Filing Date
- 2025-06-26
- Publication Date
- 2026-06-30
AI Technical Summary
The insulation structure of existing single crystal furnaces is made of graphite, which is easily damaged. On the other hand, the insulation structure made of carbon-carbon composite material has low material cleanliness, which causes impurities to enter the polycrystalline silicon raw material, affecting the quality of single crystal silicon and resulting in poor insulation effect.
It adopts a double-layer insulation structure design. The inner insulation structure is made of isostatic graphite, and the outer insulation structure is made of carbon-carbon composite material or carbon-ceramic material. The inner layer has high cleanliness and the outer layer has high strength. Combined with the cover, it forms a cavity to reduce heat transfer and improve the insulation effect and material cleanliness.
It improves the quality of monocrystalline silicon, reduces the risk of damage to the insulation structure, and enhances the insulation effect and material cleanliness.
Smart Images
Figure CN224430787U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of semiconductor technology, and in particular to heat preservation structures and single crystal furnaces. Background Technology
[0002] A single crystal furnace is a device used to produce single crystal silicon rods. Single crystal silicon rods can be made from polycrystalline silicon raw materials molten in the furnace through Czochralski or zone melting methods. The single crystal silicon rods can then be cut into wafers for use in chip manufacturing or solar cell production.
[0003] A single crystal furnace mainly consists of a furnace body structure, a heating system, a crystal growth mechanism, and an auxiliary system. The heating system includes a thermal insulation structure (i.e., a thermal field structure), which keeps the polycrystalline silicon raw material in the single crystal furnace at a suitable temperature.
[0004] In existing solutions, the insulation structure of the single crystal furnace is made of graphite or carbon-carbon composite material. If the insulation structure is made of graphite, it is easily damaged due to the low strength of graphite. If the insulation structure is made of carbon-carbon composite material, the low cleanliness of carbon-carbon composite material will cause impurities to enter the polycrystalline silicon raw material, affecting the quality of the single crystal silicon. Utility Model Content
[0005] This invention provides a thermal insulation structure and a single crystal furnace, which can improve the quality of single crystal silicon while reducing the risk of damage to the thermal insulation structure, and improving the thermal insulation effect and material cleanliness.
[0006] To achieve the above objectives, the present invention adopts the following technical solution:
[0007] In a first aspect, a thermal insulation structure is provided, which is applied to a single crystal furnace. The thermal insulation structure includes: an inner thermal insulation structure; an outer thermal insulation structure, which is sleeved on the outside of the inner thermal insulation structure, wherein the material cleanliness of the inner thermal insulation structure is greater than that of the outer thermal insulation structure, and the material strength of the outer thermal insulation structure is greater than that of the inner thermal insulation structure; a first cover connecting the top of the inner thermal insulation structure and the top of the outer thermal insulation structure; and a second cover connecting the bottom of the inner thermal insulation structure and the bottom of the outer thermal insulation structure. The inner thermal insulation structure, the outer thermal insulation structure, the first cover, and the second cover constitute a cavity.
[0008] Based on this, the outer insulation structure is fitted over the outer side of the inner insulation structure. Since the inner insulation structure has a higher material cleanliness than the outer insulation structure, the higher cleanliness of the inner insulation structure reduces impurities entering the polycrystalline silicon raw material, thus improving the quality of the monocrystalline silicon. Simultaneously, because the outer insulation structure has a higher material strength than the inner insulation structure, it can protect the inner insulation structure, reducing the risk of damage. Furthermore, since the top of the inner insulation structure is connected to the top of the outer insulation structure with a first cover, and the bottom of the inner insulation structure is connected to the bottom of the outer insulation structure with a second cover, the inner insulation structure, the outer insulation structure, the first cover, and the second cover form a cavity. This reduces heat transfer between the inner and outer sides of the insulation structure, improving its insulation effect. In summary, this invention improves the quality of monocrystalline silicon while reducing the risk of insulation structure damage, and enhances both insulation effect and material cleanliness.
[0009] In conjunction with the first aspect, in some embodiments of the first aspect, the cavity is filled with graphite felt.
[0010] In conjunction with the first aspect, in some embodiments of the first aspect, the first cover is provided with a first positioning structure, and the second cover is provided with a second positioning structure that cooperates with the first positioning structure.
[0011] In conjunction with the first aspect, in some embodiments of the first aspect, the first positioning structure is a positioning groove and the second positioning structure is a positioning protrusion, or the first positioning structure is a positioning protrusion and the second positioning structure is a positioning groove.
[0012] In conjunction with the first aspect, in some embodiments of the first aspect, the inner insulation structure and the outer insulation structure are annular structures.
[0013] In conjunction with the first aspect, in some embodiments of the first aspect, the first cover or the second cover is provided with at least one through hole, the through hole connecting the cavity and the external space of the insulation structure.
[0014] In conjunction with the first aspect, in some embodiments of the first aspect, the first cover or the second cover is provided with a plurality of through holes, which are distributed circumferentially along the cover.
[0015] In conjunction with the first aspect, in some embodiments of the first aspect, the plurality of through holes are evenly distributed along the circumference of the cover.
[0016] In conjunction with the first aspect, in some embodiments of the first aspect, the inner insulation structure is made of isostatically pressed graphite, and the outer insulation structure is made of carbon-carbon composite material or carbon-ceramic material.
[0017] In a second aspect, a single crystal furnace is provided, which includes the heat preservation structure provided in the first aspect and any of its embodiments.
[0018] The technical effects brought about by the second aspect can be referred to the technical effects brought about by the different implementation methods of the first aspect mentioned above, and will not be repeated here. Attached Figure Description
[0019] Figure 1 A perspective view of a thermal insulation structure provided by this utility model;
[0020] Figure 2 A cross-sectional view of a thermal insulation structure provided by this utility model.
[0021] Figure label:
[0022] Inner insulation structure-101, outer insulation structure-102, first cover-103, second cover-104, through hole-105. Detailed Implementation
[0023] In the description of this utility model, unless otherwise stated, "a plurality of" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of a single item or a plurality of items. For example, at least one of a, b, or c can represent: a, b, c, ab, ac, bc, or abc, where a, b, and c can be single or multiple.
[0024] Furthermore, to facilitate a clear description of the technical solutions of the embodiments of this utility model, the terms "first" and "second" are used in the embodiments of this utility model to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and the terms "first" and "second" are not necessarily different.
[0025] In this embodiment of the invention, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in this embodiment of the invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner for ease of understanding.
[0026] It is understood that the term "embodiment" used throughout the specification means that a specific feature, structure, or characteristic related to an embodiment is included in at least one embodiment of the present invention. Therefore, the various embodiments throughout the specification do not necessarily refer to the same embodiment. Furthermore, these specific features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. It is understood that in the various embodiments of the present invention, the sequence number of each process does not imply the order of execution; the execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
[0027] It is understood that in this utility model, "when," "if," and "if" all refer to the corresponding processing that will be carried out under certain objective circumstances, and are not limited to a specific time, nor do they require a judgment action to be performed, nor do they imply any other limitations.
[0028] It is understood that some optional features in the embodiments of this utility model can be implemented independently in certain scenarios without relying on other features, such as the current solution on which they are based, to solve the corresponding technical problems and achieve the corresponding effects. Alternatively, they can be combined with other features as needed in certain scenarios. Correspondingly, the device given in the embodiments of this utility model can also implement these features or functions, which will not be elaborated here.
[0029] In this utility model, unless otherwise specified, the same or similar parts between the various embodiments can be referred to each other. In the various embodiments and implementation methods of this utility model, unless otherwise specified or logically conflicting, the terminology and / or descriptions between different embodiments and between the implementation methods of different embodiments are consistent and can be mutually referenced. The technical features in different embodiments and between the implementation methods of different embodiments can be combined according to their inherent logical relationships to form new embodiments, implementation methods, implementation methods, or implementation approaches. The following embodiments of this utility model do not constitute a limitation on the scope of protection of this utility model.
[0030] A single crystal furnace is a device used to produce single crystal silicon rods. Single crystal silicon rods can be made from polycrystalline silicon raw materials molten in the furnace through Czochralski or zone melting methods. The single crystal silicon rods can then be cut into wafers for use in chip manufacturing or solar cell production.
[0031] A single crystal furnace mainly consists of a furnace body structure, a heating system, a crystal growth mechanism, and auxiliary systems. The heating system includes an insulation structure, which keeps the polycrystalline silicon raw material in the furnace at a suitable temperature.
[0032] In existing solutions, the insulation structure of the single crystal furnace is made of graphite or carbon-carbon composite material. If the insulation structure is made of graphite, it is easily damaged due to the low strength of graphite. If the insulation structure is made of carbon-carbon composite material, the low cleanliness of carbon-carbon composite material will cause impurities to enter the polycrystalline silicon raw material, affecting the quality of the single crystal silicon. In addition, the single-layer structure of the insulation structure also leads to poor insulation effect.
[0033] To address the aforementioned problems, this utility model provides a heat insulation structure, which is applied to a single crystal furnace, such as... Figure 1 or Figure 2 As shown, the thermal insulation structure 10 includes: an inner thermal insulation structure 101; an outer thermal insulation structure 102, which is sleeved on the outside of the inner thermal insulation structure 101, wherein the cleanliness of the material of the inner thermal insulation structure 101 is greater than that of the material of the outer thermal insulation structure 102, and the material strength of the outer thermal insulation structure 102 is greater than that of the inner thermal insulation structure 101; a first cover 103, which connects the top of the inner thermal insulation structure 101 and the top of the outer thermal insulation structure; and a second cover 104, which connects the bottom of the inner thermal insulation structure 101 and the bottom of the outer thermal insulation structure; the inner thermal insulation structure 101, the outer thermal insulation structure, the first cover 103, and the second cover 104 constitute a cavity.
[0034] Based on this, the outer insulation structure 102 is sleeved on the outside of the inner insulation structure 101. Since the material cleanliness of the inner insulation structure 101 is greater than that of the outer insulation structure 102, the higher cleanliness of the inner insulation structure 101 can reduce impurities entering the polycrystalline silicon raw material, thus improving the quality of the monocrystalline silicon. Simultaneously, since the material strength of the outer insulation structure 102 is greater than that of the inner insulation structure 101, the outer insulation structure 102 can protect the inner insulation structure 101, reducing the risk of damage to the insulation structure 101. Furthermore, since the inner... The top of the inner insulation structure 101 and the top of the outer insulation structure are connected to a first cover 103, and the bottom of the inner insulation structure 101 and the bottom of the outer insulation structure are connected to a second cover 104. The inner insulation structure 101, the outer insulation structure, the first cover 103 and the second cover 104 form a cavity, which can reduce heat transfer between the inner and outer sides of the insulation structure 10 and improve the insulation effect of the insulation structure 10. In summary, the solution of this utility model can improve the quality of monocrystalline silicon while reducing the risk of damage to the insulation structure 10 and improving the insulation effect and material cleanliness.
[0035] In some embodiments, the inner insulation structure 101 is made of isostatic graphite, which is an isotropic high-purity graphite material and is manufactured using an isostatic pressing process. On the one hand, isostatic graphite has a uniform microstructure and excellent thermal properties, which can improve the quality of monocrystalline silicon. On the other hand, isostatic graphite has a high degree of cleanliness, which can reduce impurities entering the polycrystalline silicon raw material.
[0036] In some embodiments, the outer insulation structure 102 is made of a carbon-carbon composite material. Carbon-carbon composite materials are high-performance materials with carbon fiber as reinforcement and pyrolytic carbon or graphite as the matrix. They possess unique advantages such as lightweight, resistance to ultra-high temperatures, high strength, low thermal expansion, and thermal shock resistance. They can protect the inner insulation structure 101, reduce the risk of damage to the insulation structure 10, and improve the insulation effect. For example, the carbon-carbon composite material can be a material made by graphitizing carbon fiber insulation felt with phenolic resin, a material made by carbonizing needle-punched carbon felt or three-dimensionally woven carbon fiber reinforced by CVD or resin impregnation, or a material made by coating a carbon / carbon surface with SiC or melt-infiltrating silicon. Of course, the outer insulation structure 102 can also be made of other carbon-carbon composite materials; this invention does not impose specific limitations on this.
[0037] In some other embodiments, the outer thermal insulation structure 102 may also be made of carbon-ceramic material. Exemplarily, the carbon-ceramic material may be carbon fiber reinforced silicon carbide or carbon fiber reinforced carbon-silicon carbide. Of course, the outer thermal insulation structure 102 may also be made of other carbon-ceramic materials, and this invention does not impose specific limitations on this.
[0038] In some embodiments, the cavity is filled with graphite soft felt. Due to the excellent compressibility and filling properties, extremely low thermal conductivity and excellent thermal shock stability of graphite soft felt, the thermal insulation effect of the insulation structure 10 can be further improved. In addition, since the graphite soft felt is placed inside the cavity, the dust scattered by the graphite soft felt can be reduced, and the cleanliness of the insulation structure 10 can be improved.
[0039] In some embodiments, the first cover is provided with a first positioning structure, and the second cover is provided with a second positioning structure that cooperates with the first positioning structure. Thus, since the first and second covers can be positioned relative to each other through the positioning structures, when multiple insulation structures are used in combination, the positioning structures can be used to fix the first cover of one insulation structure to the positioning structure of the second cover of another insulation structure, improving the efficiency of installing multiple insulation structures.
[0040] For example, the first positioning structure is a positioning groove and the second positioning structure is a positioning protrusion, or the first positioning structure is a positioning protrusion and the second positioning structure is a positioning groove. Of course, the first positioning structure and the second positioning structure can be other positioning structures that can cooperate with each other, and this utility model does not impose specific limitations on them.
[0041] In some embodiments, the inner insulation structure 101 and the outer insulation structure 102 are annular structures, such as elliptical ring structures or circular ring structures. Preferably, as Figure 1 As shown, the inner insulation structure 101 and the outer insulation structure 102 are circular ring structures.
[0042] In some embodiments, the first cover 103 or the second cover 104 is provided with at least one through hole 105, which connects the cavity and the external space of the insulation structure 10. This facilitates the removal of air during the evacuation process of the cavity.
[0043] For example, the number of through holes 105 in the first cover 103 or the second cover 104 can be one or more, and the present invention does not impose a specific limitation on this.
[0044] Preferred, such as Figure 1 or Figure 2 As shown, the first cover 103 or the second cover 104 is provided with a plurality of through holes 105, which are distributed circumferentially along the cover. In some embodiments, the plurality of through holes 105 are evenly distributed circumferentially along the cover. In this way, the efficiency of air removal can be improved during the vacuuming process of the cavity.
[0045] The material of the first cover 103 or the second cover 104 can be carbon-carbon composite material.
[0046] This utility model also provides a single crystal furnace, which includes the heat preservation structure 10 provided in the above specific embodiments.
[0047] In addition to the aforementioned heat preservation structure 10, the single crystal furnace may also include other components, such as furnace body structure, crystal growth mechanism and auxiliary system, etc. This utility model does not impose specific limitations in this regard.
[0048] Although the present invention has been described herein in conjunction with various embodiments, those skilled in the art will understand and implement other variations of the disclosed embodiments by reviewing the accompanying drawings, the disclosure, and the appended claims in carrying out the claimed invention. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude a plurality. A single processor or other unit can implement several functions listed in the claims. While different dependent claims may recite certain measures, this does not mean that these measures cannot be combined to produce good results.
[0049] Although the present invention has been described in conjunction with specific features and embodiments, it is obvious that various modifications and combinations can be made thereto without departing from the spirit and scope of the present invention. Accordingly, this specification and drawings are merely exemplary descriptions of the present invention as defined by the appended claims, and are considered to cover any and all modifications, variations, combinations, or equivalents within the scope of the present invention. Clearly, those skilled in the art can make various alterations and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such modifications and modifications of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and modifications.
Claims
1. An insulating structure, characterized by The insulation structure is applied to a single crystal furnace, and the insulation structure includes: Inner insulation structure; An outer insulation structure is fitted over the outer side of the inner insulation structure. The cleanliness of the material of the inner insulation structure is greater than that of the outer insulation structure, and the strength of the material of the outer insulation structure is greater than that of the inner insulation structure. The first cover connects the top of the inner insulation structure and the top of the outer insulation structure; The second cover connects the bottom of the inner insulation structure and the bottom of the outer insulation structure; The inner insulation structure, the outer insulation structure, the first cover, and the second cover constitute a cavity.
2. The heat retaining structure according to claim 1, wherein The cavity is filled with graphite felt.
3. The heat retaining structure according to claim 1, wherein The first cover is provided with a first positioning structure, and the second cover is provided with a second positioning structure that cooperates with the first positioning structure.
4. The heat retaining structure according to claim 3, wherein The first positioning structure is a positioning groove and the second positioning structure is a positioning protrusion, or the first positioning structure is a positioning protrusion and the second positioning structure is a positioning groove.
5. The heat retaining structure according to claim 1, wherein The inner insulation structure and the outer insulation structure are ring structures.
6. The heat retaining structure according to claim 5, wherein The first cover or the second cover is provided with at least one through hole, which connects the cavity and the external space of the insulation structure.
7. The thermal insulation structure according to claim 6, characterized in that, The first cover or the second cover is provided with a plurality of through holes, which are distributed along the circumference of the cover.
8. The thermal insulation structure according to claim 7, characterized in that, The plurality of through holes are evenly distributed along the circumference of the cover.
9. The thermal insulation structure according to claim 1, characterized in that, The inner insulation structure is made of isostatically pressed graphite, and the outer insulation structure is made of carbon-carbon composite material or carbon-ceramic material.
10. A single crystal furnace, characterized in that, The single crystal furnace includes the heat preservation structure as described in any one of claims 1-9.