Resistance type heating silicon carbide crystal growth thermal field structure
By adding a water-cooled cooling cover to the periphery of the insulation felt of the silicon carbide crystal growth equipment, a hollow temperature insulation layer is formed, which solves the problem of large temperature fluctuations in crystal growth equipment over long and high temperatures, and achieves higher temperature accuracy and more stable crystal growth quality.
Patent Information
- Application Number
- CN202421884866.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-06
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2034-08-06
AI Technical Summary
During the long-term and high-temperature crystal growth process of existing silicon carbide crystal growth equipment, the vacuum cavity and graphite insulation felt are prone to heat leakage, resulting in large fluctuations in the crystal growth temperature, making it difficult to maintain temperature accuracy, and affecting the crystal growth quality.
The resistive heating silicon carbide long crystal heat field structure is adopted. By adding a water-cooled cooling cover to the periphery of the insulation felt, a hollow temperature insulation layer is formed, combined with the internal insulation felt, the external influence of the high temperature is reduced and the temperature control accuracy is improved.
It effectively reduces the fluctuations in crystal growth temperature, improves the accuracy and stability of temperature, and improves the quality of crystal growth.
Smart Images
Figure CN222861716U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of crystal growth equipment, in particular to a resistive heating silicon carbide crystal growth thermal field structure. Background Art
[0002] Please refer to Figure 1 The existing silicon carbide crystal growth equipment generally arranges a graphite heater 02, a graphite insulation felt 03 and a vacuum chamber 04 in sequence on the periphery of a graphite crucible 01, and the thermal field control of the graphite crucible 01 is achieved through the graphite heater 02, the graphite insulation felt 03 and the vacuum chamber 04.
[0003] However, the inventors have discovered that in the existing silicon carbide crystal growth equipment, the graphite heater 02 is insulated only by the vacuum chamber 04 and the graphite insulation felt 03. During the long-term (e.g., about 200 hours) and high-temperature (e.g., 2300°C) crystal growth process, the vacuum chamber 04 and the graphite insulation felt 03 are still prone to heat leakage, resulting in large fluctuations in the crystal growth temperature, difficulty in maintaining the accuracy of the crystal growth temperature, and unstable crystal growth quality. Utility Model Content
[0004] The utility model aims to provide a resistive heating silicon carbide crystal growth thermal field structure, which can reduce the fluctuation of crystal growth temperature, maintain the accuracy of crystal growth temperature, and improve the quality of crystal growth.
[0005] The embodiment of the utility model is achieved as follows:
[0006] The utility model provides a resistive heating silicon carbide crystal growth thermal field structure, which comprises a water-cooled vacuum cavity, a water-cooled cooling cover, a thermal insulation felt and a heater;
[0007] The water-cooling hood is arranged inside the water-cooling vacuum cavity, and the side wall of the water-cooling hood is spaced apart from the side wall of the water-cooling vacuum cavity, so that a hollow area is formed between the side wall of the water-cooling hood and the side wall of the water-cooling vacuum cavity, and the side wall of the water-cooling hood, the side wall of the water-cooling vacuum cavity and the hollow area constitute a hollow thermal insulation layer;
[0008] The heat preservation felt is arranged inside the water-cooling cover, the heater is arranged inside the heat preservation felt, and the interior of the heater is used for placing the crystal growth crucible.
[0009] In an optional embodiment, water channels are provided in the side walls of the water-cooled cooling cover and the side walls of the water-cooled vacuum chamber, and the water channels are used to pass cooling water.
[0010] In an optional embodiment, the outer side of the insulation felt is attached to the inner side of the water-cooled cooling cover, the inner side of the insulation felt is spaced apart from the outer side of the heater, and the center of the heater is used to place the crystal growth crucible.
[0011] In an optional embodiment, the distance a between the side wall of the water-cooled cooling cover and the side wall of the water-cooled vacuum chamber ranges from 100 mm to 140 mm.
[0012] In an optional embodiment, the distance b between the inner side of the insulation felt and the outer side of the heater ranges from 40 mm to 60 mm; the distance c between the inner side of the heater and the outer side of the crystal growth crucible ranges from 70 mm to 95 mm.
[0013] The beneficial effects of the resistive heating silicon carbide crystal growth thermal field structure provided by the embodiment of the utility model include:
[0014] By adding a water-cooling cooling hood on the periphery of the thermal insulation felt, the side wall of the water-cooling cooling hood is spaced apart from the side wall of the water-cooling vacuum chamber, so that a hollow area is formed between the side wall of the water-cooling cooling hood and the side wall of the water-cooling vacuum chamber. The side wall of the water-cooling cooling hood, the side wall of the water-cooling vacuum chamber and the hollow area constitute a hollow thermal insulation layer, which, combined with the internal thermal insulation felt, makes the high temperature inside the thermal insulation felt (the area where the crystal growth crucible is located) less affected by the external environment, which can reduce the fluctuation of the crystal growth temperature, maintain the accuracy of the crystal growth temperature, and improve the crystal growth quality. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the utility model and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying creative work.
[0016] Figure 1 It is a schematic diagram of the full cross-section structure of the existing silicon carbide crystal growth equipment;
[0017] Figure 2 A schematic cross-sectional view of a thermal field structure for resistive heating of silicon carbide crystal growth provided by an embodiment of the utility model;
[0018] Figure 3 This is a schematic diagram of the longitudinal cross-section of the thermal field structure for resistive heating of silicon carbide crystal growth provided in an embodiment of the utility model.
[0019] Icons: 01-graphite crucible; 02-graphite heater; 03-graphite insulation felt; 04-vacuum chamber; 1-crystal growth crucible; 2-heater; 3-insulation felt; 4-water-cooled cooling hood; 5-water-cooled vacuum chamber. DETAILED DESCRIPTION
[0020] In order to make the purpose, technical scheme and advantages of the embodiments of the utility model clearer, the technical scheme in the embodiments of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Generally, the components of the embodiments of the utility model described and shown in the drawings here can be arranged and designed in various different configurations.
[0021] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the present invention to be protected, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0022] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.
[0023] In the description of the present utility model, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, or the orientation or position relationship in which the utility model product is usually placed when in use, which is only for the convenience of describing the utility model and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0024] In addition, the terms "horizontal", "vertical" and the like do not mean that the components are required to be absolutely horizontal or suspended, but can be slightly tilted. For example, "horizontal" only means that its direction is more horizontal than "vertical", and does not mean that the structure must be completely horizontal, but can be slightly tilted.
[0025] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.
[0026] Please refer to Figure 2 and Figure 3 The present embodiment provides a resistive heating silicon carbide crystal growth thermal field structure, which includes a water-cooled vacuum chamber 5, a water-cooled cooling cover 4, a thermal insulation felt 3 and a heater 2.
[0027] Among them, the water-cooled cooling hood 4 is arranged inside the water-cooled vacuum cavity 5, and the side wall of the water-cooled cooling hood 4 is spaced apart from the side wall of the water-cooled vacuum cavity 5, so that a hollow area is formed between the side wall of the water-cooled cooling hood 4 and the side wall of the water-cooled vacuum cavity 5, and the side wall of the water-cooled cooling hood 4, the side wall of the water-cooled vacuum cavity 5 and the hollow area constitute a hollow thermal insulation layer; water channels are arranged in the side walls of the water-cooled cooling hood 4 and the side walls of the water-cooled vacuum cavity 5, and the water channels are used to pass cooling water. The arrangement of the water channels can be various, and the side walls can be evenly cooled.
[0028] The insulation felt 3 is arranged inside the water-cooled cooling cover 4, and the heater 2 is arranged inside the insulation felt 3, and the heater 2 can be a resistive heater 2. The interior of the heater 2 is used to place the crystal growth crucible 1, and the crystal growth crucible 1 can be a graphite crucible.
[0029] By adding a water-cooled cooling hood 4 on the periphery of the thermal insulation felt 3, the side wall of the water-cooled cooling hood 4 is spaced apart from the side wall of the water-cooled vacuum chamber 5, so that a hollow area is formed between the side wall of the water-cooled cooling hood 4 and the side wall of the water-cooled vacuum chamber 5. The side wall of the water-cooled cooling hood 4, the side wall of the water-cooled vacuum chamber 5 and the hollow area constitute a hollow thermal insulation layer, and combined with the internal thermal insulation felt 3, the high temperature inside the thermal insulation felt 3 (the area where the crystal growth crucible 1 is located) is less affected by the external environment, which can reduce the fluctuation of the crystal growth temperature, maintain the accuracy of the crystal growth temperature, and improve the crystal growth quality.
[0030] Preferably, the outer side surface of the insulation felt 3 is attached to the inner side surface of the water-cooled cooling cover 4, so that the water-cooled cooling cover 4 can be used to support the insulation felt 3. The inner side surface of the insulation felt 3 is spaced apart from the outer side surface of the heater 2, and the center of the heater 2 is used to place the crystal growth crucible 1.
[0031] The outer diameter of the water-cooled vacuum chamber 5 may be 1000 mm to 1200 mm, for example, 1081 mm, and the wall thickness of the water-cooled vacuum chamber 5 may be 20 mm to 30 mm. The distance a between the side wall of the water-cooled cooling cover 4 and the side wall of the water-cooled vacuum chamber 5 may be in the range of 100 mm to 140 mm, for example, 122.5 mm. The outer diameter of the water-cooled cooling cover 4 may be 750 mm to 800 mm, for example, 770 mm, and the wall thickness of the water-cooled cooling cover 4 may be 10 mm to 30 mm.
[0032] The distance b between the inner side of the insulation felt 3 and the outer side of the heater 2 ranges from 40 mm to 60 mm, for example, 50 mm; the distance c between the inner side of the heater 2 and the outer side of the crystal growth crucible 1 ranges from 70 mm to 95 mm, for example, 81.5 mm.
[0033] The water-cooled vacuum chamber 5, the water-cooled cooling cover 4, the thermal insulation felt 3 and the heater 2 each include two detachable halves of the same front and rear shapes and sizes. This not only makes it easy to assemble the components, but also the water channels on the water-cooled vacuum chamber 5 and the water-cooled cooling cover 4 can mainly extend in the longitudinal direction, reducing the difficulty of design and production and ensuring uniform cooling.
[0034] Of course, in other embodiments, the water-cooled vacuum chamber 5, the water-cooled cooling cover 4, the thermal insulation felt 3 and the heater 2 can also be designed as a structure in which the upper and lower covers are covered, which can also achieve the technical effect of this embodiment.
[0035] Example
[0036] The periphery of the crystal growth crucible 1 is sequentially provided with a heater 2, a thermal insulation felt 3, a water-cooled cooling hood 4 and a water-cooled vacuum chamber 5. The distance c from the outer side of the crystal growth crucible 1 to the inner side of the heater 2 is 81.5 mm. The distance b from the outer side of the heater 2 to the inner side of the thermal insulation felt 3 is 50 mm. The outer diameter of the thermal insulation felt 3 is 726 mm. The outer diameter of the water-cooled cooling hood 4 is 770 mm. The distance a between the side wall of the water-cooled cooling hood 4 and the side wall of the water-cooled vacuum chamber 5 is 122.5 mm. The outer diameter of the water-cooled vacuum chamber 5 can be 1081 mm.
[0037] During the crystal growth process, the vacuum degree of 3.75 torr is maintained in the hollow area of the hollow insulation layer, and cooling water is introduced into the water-cooled vacuum cavity 5 and the water-cooled cooling cover 4. The statistics of various working parameters of the resistive heating silicon carbide crystal growth thermal field structure are shown in the following table:
[0038]
[0039]
[0040] In the table, the temperature of crystal growth crucible 1 refers to the measured temperature at the center of the bottom surface of crystal growth crucible 1. It can be seen from the table that the maximum temperature of crystal growth crucible 1 in a day is 2251.8℃, the minimum is 2251.2℃, and the maximum drop is 0.6℃ (the maximum drop of existing equipment is generally more than 5℃). It can be seen that the fluctuation of crystal growth temperature is very small, so the controller adjusts the power of heater 2 less (that is, the fluctuation of heater 2 power is very small), which is conducive to maintaining the accuracy of crystal growth temperature and improving crystal growth quality.
[0041] The beneficial effects of the resistive heating silicon carbide crystal growth thermal field structure provided in this embodiment include:
[0042] By adding a water-cooled cooling hood 4 on the periphery of the thermal insulation felt 3, the side wall of the water-cooled cooling hood 4 is spaced apart from the side wall of the water-cooled vacuum chamber 5, so that a hollow area is formed between the side wall of the water-cooled cooling hood 4 and the side wall of the water-cooled vacuum chamber 5. The side wall of the water-cooled cooling hood 4, the side wall of the water-cooled vacuum chamber 5 and the hollow area constitute a hollow thermal insulation layer, and combined with the internal thermal insulation felt 3, the high temperature inside the thermal insulation felt 3 (the area where the crystal growth crucible 1 is located) is less affected by the external environment, which can reduce the fluctuation of the crystal growth temperature, maintain the accuracy of the crystal growth temperature, and improve the crystal growth quality.
[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may be subject to various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.
Claims
1. A resistive heating silicon carbide crystal growth thermal field structure, characterized in that: The resistive heating silicon carbide crystal growth thermal field structure comprises a water-cooled vacuum cavity (5), a water-cooled cooling cover (4), a thermal insulation felt (3) and a heater (2); The water-cooled cooling cover (4) is arranged inside the water-cooled vacuum cavity (5), and the side wall of the water-cooled cooling cover (4) is spaced apart from the side wall of the water-cooled vacuum cavity (5), so that a hollow area is formed between the side wall of the water-cooled cooling cover (4) and the side wall of the water-cooled vacuum cavity (5), and the side wall of the water-cooled cooling cover (4), the side wall of the water-cooled vacuum cavity (5) and the hollow area constitute a hollow thermal insulation layer; The thermal insulation felt (3) is arranged inside the water-cooling hood (4), the heater (2) is arranged inside the thermal insulation felt (3), and the interior of the heater (2) is used to place a crystal growth crucible (1).
2. The resistive heating silicon carbide crystal growth thermal field structure according to claim 1, characterized in that: Water channels are provided in the side walls of the water-cooling cooling cover (4) and the side walls of the water-cooling vacuum cavity (5), and the water channels are used to pass cooling water.
3. The resistive heating silicon carbide crystal growth thermal field structure according to claim 1, characterized in that: The outer side surface of the insulation felt (3) is attached to the inner side surface of the water-cooled cooling cover (4), the inner side surface of the insulation felt (3) is spaced apart from the outer side surface of the heater (2), and the center of the heater (2) is used to place the crystal growth crucible (1).
4. The resistive heating silicon carbide crystal growth thermal field structure according to claim 1, characterized in that: The distance a between the side wall of the water-cooling cooling cover (4) and the side wall of the water-cooling vacuum chamber (5) ranges from 100 mm to 140 mm.
5. The resistive heating silicon carbide crystal growth thermal field structure according to claim 3, characterized in that: The distance b between the inner side surface of the thermal insulation felt (3) and the outer side surface of the heater (2) ranges from 40 mm to 60 mm; the distance c between the inner side surface of the heater (2) and the outer side surface of the crystal growth crucible (1) ranges from 70 mm to 95 mm.