Single crystal furnace with multi-section heating structure

Abstract

The invention belongs to the technical field of single crystal furnaces, and particularly relates to a single crystal furnace with a multi-section heating structure, which comprises a control device, a furnace body is fixed on one side of the control device, a support frame is mounted at the top end of the control device, and a crystal pulling assembly is connected to one side, close to the furnace body, of the support frame through a lifting device. A first lifting rod is arranged in the crystal pulling assembly, a clamping seat is fixed at the bottom end of the first lifting rod, an isolation pipe is fixed in the furnace body, and a crucible is arranged in the isolation pipe; a plurality of resistance heaters are arranged in the isolation pipe; by arranging the multiple resistance heaters, the crucible can be heated more quickly to melt polycrystalline silicon particles, the multiple resistance heaters are separated after melting, the multiple resistance heaters can heat the interior of the furnace body at different heights, the temperature of the upward moving path of a silicon rod is gradually reduced, and the situation that the cooling speed of the silicon rod is too high can be avoided.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of single crystal furnaces, in particular to a single crystal furnace with a multi-section heating structure. BACKGROUND

[0002] A single crystal furnace is a core equipment for growing high-purity single crystals. By precisely controlling the temperature, vacuum environment, gas atmosphere, and crystal / crucible movement in the furnace, the raw materials such as polycrystalline silicon are melted into a liquid, and then a single crystal with complete structure and high purity is cultivated using the Czochralski method.

[0003] A single crystal furnace with a new heater structure is disclosed in a Chinese patent with publication number CN118773726A. The single crystal furnace includes a furnace cylinder, an insulation sleeve, a crucible device, and a heater device. The transverse support mechanism is connected to the heating sheet mechanism and horizontally passes through the side wall of the insulation sleeve in the horizontal direction. The transverse electrode mechanism is connected to the transverse support mechanism and horizontally passes through the side wall of the furnace cylinder in the horizontal direction. The transverse electrode mechanism is used for electrical connection with an external power supply, enhancing the stability of the overall structure.

[0004] The above technical solution concentrates the heating area in one location, resulting in only a single location being able to be heated or cooled during the heating process. During the crystal pulling process, the crystal rod is moved to a low-temperature zone after being pulled out, and the large temperature difference between the low-temperature zone and the high-temperature zone, as well as the short length of the transition zone, can cause internal thermal stress of the crystal rod to affect the quality of the crystal rod.

[0005] Therefore, the application provides a single crystal furnace with a multi-section heating structure. SUMMARY

[0006] To make up for the deficiencies of the prior art and solve at least one technical problem raised in the background.

[0007] The technical solution adopted by the application to solve its technical problem is as follows: The single crystal furnace with a multi-section heating structure comprises a control device, one side of the control device is fixed with a furnace body, the top end of the control device is installed with a support frame, the side close to the furnace body of the support frame is connected with a crystal pulling assembly through a lifting device, the inside of the crystal pulling assembly is provided with a first lifting rod, the bottom end of the first lifting rod is fixed with a clamping seat, the bottom end of the clamping seat can clamp a seed crystal, the inside of the furnace body is fixed with an isolation pipe, the inside of the isolation pipe is provided with a crucible, the bottom end inside the furnace body is installed with a rotating assembly, the rotating shaft end of the rotating assembly is fixedly connected with the bottom end of the crucible. The inside of the isolation pipe is provided with a plurality of resistance heaters, adjacent two resistance heaters are provided with a gap, the top end of each resistance heater is installed with a plurality of temperature sensors at equal intervals, the height of the temperature sensor is less than the size of the gap between the resistance heaters, and the two sides of the bottom end inside the furnace body are installed with first motors. When the first motor rotates forward, the distance between the resistance heaters increases, and when the first motor reverses, the distance between the resistance heaters decreases.

[0008] Preferably, the lowermost resistance heater is fixed on both sides with a fixed plate, the fixed plate is fixedly connected with the isolation tube, the shaft end of the first motor penetrates through the inside of the fixed plate, and the shaft end is fixed with a rotating column one, the uppermost resistance heater is fixed on both sides with a top connecting plate, one side of the top connecting plate is fixed with a rotating tube three, and the lower side of the top connecting plate is provided with a movable plate two, the movable plate two is fixedly connected with one of the resistance heaters, one side of the movable plate two is rotatably connected with a rotating tube two, the top end of the rotating tube two is fixed with a rotating column three, the rotating column three is inserted into the inside of the rotating tube three, the upper side of the fixed plate is provided with a movable plate one, the movable plate one is also fixedly connected with one of the resistance heaters, one side of the movable plate one is rotatably connected with a rotating tube one, the top end of the rotating tube one is fixed with a rotating column two, the rotating column two is inserted into the inside of the rotating tube two, the rotating column one is inserted into the inside of the rotating tube one, the outside of the rotating column one, the rotating column two and the rotating column three are all provided with a spiral sliding groove, the top end and the bottom end of the spiral sliding groove are both provided with a limiting groove, the inside of the rotating tube one, the rotating tube two and the rotating tube three are both fixed with a protrusion, and the protrusion is slidingly connected in the inside of the spiral sliding groove.

[0009] Preferably, the inside of the clamping seat is fixed with a spiral heat absorption pipe at the bottom end, the side of the furnace body away from the control device is fixed with a box body, the inside of the box body is provided with a heating pot, and the lower side of the heating pot is provided with a heat dissipation fin. The spiral heat absorption pipe absorbs the heat of the seed crystal clamped by the clamping seat, and the heat dissipation fin conducts and volatilizes the heat.

[0010] Preferably, the side of the top end of the box body is installed with a water pump, the outside end of the spiral heat absorption pipe is fixed with an outlet pipe, the inside end of the spiral heat absorption pipe is fixed with an inlet pipe, the other end of the inlet pipe is connected with the outlet end of the water pump, the inlet end of the water pump is connected with the outlet end of the heat dissipation fin through a pipeline, the other end of the outlet pipe is connected with the inlet end of the heat dissipation fin, and the bottom end of the box body is provided with an air inlet, and the inside of the air inlet is installed with a heat dissipation fan.

[0011] Preferably, the inside of the heating pot is provided with a first material turning frame, the middle part of the first material turning frame is fixed with a connecting rod, the upper side of the heating pot is provided with a second motor, and the shaft end of the second motor is fixedly connected with the top end of the connecting rod.

[0012] Preferably, the bottom end of the second motor is installed with a lifting frame, the lower side of the lifting frame away from the second motor is provided with a second lifting rod, one side of the box body is fixed with a supporting plate, and the bottom end of the second lifting rod is fixedly connected with the supporting plate.

[0013] Preferably, the two sides of the supporting plate are both provided with a guide hole, the two sides of the lifting frame are both provided with a sliding block, and the sliding block is slidingly connected in the inside of the guide hole.

[0014] Preferably, the upper part of the guide hole is provided with a bending section, and the sliding block can slide in the bending section. When the sliding block slides into the bending section from the guide hole, the lifting frame is driven by the sliding block to move towards the second lifting rod.

[0015] Preferably, the bottom end of the lifting frame is fixed with a guide rail, and the top end of the second lifting rod is fixed with a guide block which is slidingly connected outside the guide rail.

[0016] Preferably, the inside of the first material turning frame is rotatably connected with a pair of second material turning frames, the rotary shaft of the second material turning frame is rotatably connected to the inside of the connecting rod, the inside of the connecting rod is rotatably connected with a rotating rod, the bottom end of the rotating rod is fixed with a gear disc, the end of the second material turning frame is fixed with a gear, the gear and the gear disc are meshingly connected, the top end of the rotating rod is fixed with a first gear, the first gear is meshingly connected with a second gear on one side, the second gear is rotatably connected to the inside of the connecting rod, the other side of the second gear extends out from the outside of the connecting rod, and the bottom end of the lifting frame close to the connecting rod is fixed with a gear ring, the gear ring and the second gear are meshingly connected.

[0017] The beneficial effects of the present application are as follows: 1. The single crystal furnace with a multi-section heating structure can heat the crucible more quickly to melt the polysilicon particles by arranging multiple resistance heaters, and the polysilicon particles can be dispersed after melting, so that the multiple resistance heaters can heat the different heights inside the furnace body, the temperature of the path for the silicon rod to move upward gradually decreases, and the situation that the silicon rod cools too quickly can be avoided.

[0018] 2. The single crystal furnace with a multi-section heating structure can heat the seed crystal through the spiral heat absorption pipe, and the heat absorption pipe can evaporate heat through the heat dissipation fan blowing air to the heat dissipation fins, so as to heat the heating pot and preheat the polysilicon particles inside the heating pot. BRIEF DESCRIPTION OF DRAWINGS

[0019] The present application will be further described below with reference to the accompanying drawings.

[0020] Figure 1 is a perspective view of the present application; Figure 2 is a schematic view of the internal structure of the furnace body in the present application; Figure 3 is a schematic view of the resistance heater structure in the present application; Figure 4 is an exploded view of the rotating column I and the rotating pipe I in the present application; Figure 5 is a schematic view of the internal structure of the rotating pipe in the present application; Figure 6 is a schematic view of the structure of the spiral heat absorption pipe in the present application; Figure 7 is the box internal structure schematic diagram in the application; Figure 8 is the support plate structure schematic diagram in the application; Figure 9 is the rotating rod structure schematic diagram in the application.

[0021] In the figure: 1, control device; 11, furnace body; 111, isolation pipe; 112, crucible; 113, rotating assembly; 12, crystal pulling assembly; 121, support frame; 122, first lifting rod; 123, clamping seat; 124, spiral heat absorption pipe; 125, water inlet pipe; 126, water outlet pipe; 127, water pump; 128, heat dissipation fin; 13, resistance heater; 131, first motor; 132, temperature sensor; 133, fixed plate; 134, rotating column one; 1341, rotating column two; 1342, rotating column three; 135, movable plate one; 1351, movable plate two; 136, rotating pipe one; 1361, rotating pipe two; 1362, rotating pipe three; 137, top connecting plate; 138, protrusion; 139, spiral chute; 2, box; 21, heat dissipation fan; 22, heating pot; 23, support plate; 231, guide hole; 232, second lifting rod; 233, guide block; 24, lifting frame; 241, guide rail; 242, second motor; 243, first material turning frame; 244, second material turning frame; 245, connecting rod; 246, rotating rod; 247, gear ring; 248, first gear; 249, second gear. DETAILED DESCRIPTION

[0022] In order to make the technical means, creative features, purposes and effects realized by the application easy to understand, the application will be further described below in combination with specific embodiments.

[0023] As Figures 1 to 5 shown, the single crystal furnace with multi-section heating structure according to the embodiment of the application includes a control device 1, one side of the control device 1 is fixed with a furnace body 11, a support frame 121 is installed at the top end of the control device 1, the support frame 121 is connected with a crystal pulling assembly 12 through a lifting device at one side close to the furnace body 11, a first lifting rod 122 is arranged in the crystal pulling assembly 12, a clamping seat 123 is fixed at the bottom end of the first lifting rod 122, the clamping seat 123 can clamp a seed crystal at the bottom end, an isolation pipe 111 is fixed in the furnace body 11, a crucible 112 is arranged in the isolation pipe 111, a rotating assembly 113 is installed at the bottom end in the furnace body 11, the rotating shaft end of the rotating assembly 113 is fixedly connected with the bottom end of the crucible 112; The inside of the isolation tube 111 is provided with a plurality of resistance heaters 13, and adjacent two resistance heaters 13 are provided with a gap, and a plurality of temperature sensors 132 are installed at the top end of each resistance heater 13 at equal intervals, and the temperature sensor 132 is smaller in height than the size of the gap between the resistance heaters 13, and the first motor 131 is installed at the bottom end of the inside of the furnace body 11 on both sides; Wherein, when the first motor 131 rotates forward, the spacing between the resistance heaters 13 is increased, and when the first motor 131 reverses, the spacing between the resistance heaters 13 is reduced; When the crystal bar is manufactured, a single crystal furnace will be used, the single crystal furnace will heat and melt the polycrystalline silicon particles, and pull out the silicon rod through the seed crystal, and when in use, the lifting device of the support frame 121 drives the pulling crystal assembly 12 to rise from the top end of the furnace body 11, at this time the pulling crystal assembly 12 drives the first lifting rod 122 and the clamping seat 123 to separate from the inside of the furnace body 11, then the polycrystalline silicon particles are put into the inside of the crucible 112, and the seed crystal is installed at the bottom end of the clamping seat 123, after installation, the lifting device drives the pulling crystal assembly 12 to move downwards, at this time the pulling crystal assembly 12 drives the first lifting rod 122 and the clamping seat 123 to extend into the inside of the furnace body 11, the pulling crystal assembly 12 seals the top end of the furnace body 11, then the resistance heater 13 is powered on, the resistance heater 13 generates heat to heat the crucible 112, at this time the polycrystalline silicon particles in the inside of the crucible 112 are heated and melted, after melting, the first lifting rod 122 drives the clamping seat 123 to make the seed crystal at the bottom end thereof contact the liquid silicon material, then the mechanism in the inside of the pulling crystal assembly 12 pulls the first lifting rod 122 to rise, the first lifting rod 122 pulls the clamping seat 123 to make the seed crystal drive the liquid silicon material to move upwards, at the same time, the rotating assembly 113 drives the crucible 112 to rotate slowly, when the liquid silicon material rises from the liquid plane of the crucible 112, the temperature will be reduced below the melting point, at this time the silicon material will re-solidify into a solid, in this way, the seed crystal is slowly pulled up, so that the liquid silicon material forms a silicon rod at the bottom of the seed crystal; When melting polycrystalline silicon particles, the crucible 112 needs to be heated. This requires a large amount of heat inside the crucible 112, but after heating, only the melting point temperature needs to be maintained. Therefore, when heating the crucible 112, the first motor 131 is activated to move multiple resistance heaters 13, causing them to converge on the outside of the crucible 112. This allows multiple resistance heaters 13 to heat the crucible 112 simultaneously, while temperature is measured simultaneously by a temperature sensor 132 positioned below adjacent resistance heaters 13. When the polycrystalline silicon particles inside the crucible 112... Once silicon reaches its melting point, the crucible 112 requires less heat, necessitating the dispersion of multiple resistance heaters 13. At this point, the first motor 131 rotates in the opposite direction, causing the multiple resistance heaters 13 to rise and disperse. Simultaneously, the temperature sensor 132 at the top of each resistance heater 13 measures the temperature. The dispersed resistance heaters 13 then adjust according to the measured temperature, causing the temperature of the lowest resistance heater 13 to gradually decrease upwards. This method allows the silicon rod to be gradually cooled after being pulled out, thus preventing excessive temperature differences at the points where the silicon rod passes through, which could affect the molding quality of the silicon rod due to internal thermal stress.

[0024] like Figures 1 to 5 As shown, fixing plates 133 are fixed on both sides of the bottom resistance heater 13. The fixing plates 133 are fixedly connected to the isolation tube 111. The shaft end of the first motor 131 passes through the interior of the fixing plate 133, and a rotating column 134 is fixed to the shaft end. Top connecting plates 137 are fixed on both sides of the top resistance heater 13. A rotating tube 1362 is fixed on one side of the top connecting plate 137. A movable plate 1351 is provided below the top connecting plate 137. The movable plate 1351 is fixedly connected to one of the resistance heaters 13. A rotating tube 1361 is rotatably connected to one side of the movable plate 1351. A rotating column 1342 is fixed to the top of the rotating tube 1361 and inserted into the rotating tube 1362. A movable plate 135 is provided above the fixed plate 133. The movable plate 135 is also fixedly connected to one of the resistance heaters 13. A rotating tube 136 is rotatably connected to one side of the movable plate 135. A rotating column 2 1341 is fixed at the top of the rotating tube 136. The rotating column 2 1341 is inserted inside the rotating tube 2 1361. The rotating column 134 is inserted inside the rotating tube 136. A spiral groove 139 is provided on the outer side of the rotating column 134, the rotating column 2 1341 and the rotating column 3 1342. A limit groove is provided at the top and bottom of the spiral groove 139. A protrusion 138 is fixed on both sides inside the rotating tube 136, the rotating tube 2 1361 and the rotating tube 3 1362. The protrusion 138 is slidably connected inside the spiral groove 139. In the initial state, the distance between the resistance heaters 13 is at its minimum. (Reference) Figure 3After the crucible 112 is heated, the resistance heaters 13 need to be dispersed. At this time, the first motor 131 is started to rotate in the opposite direction. The first motor 131 drives the rotating column 134 to rotate. The fixed plate 133 keeps the lowest resistance heater 13 in a fixed state. The rotating column 134 at the end of the rotating shaft rotates inside the upper rotating tube 136. Due to the weight of the multiple resistance heaters 13 above, pressure is applied to the top connecting plate 137, the second movable plate 1351 and the first movable plate 135, so that the rotating tube 136, the second rotating tube 1361 and the third rotating tube 1362 remain stationary. At this time, the rotating column 134 will extend out of the interior of the rotating tube 136 under the action of the protrusion 138 and the spiral groove 139. Then the spiral groove 139 of the rotating column 134 and the protrusion 138 of the rotating tube 136 will be stuck, so that the rotating column 134 and the rotating tube 136 form a whole. At this time, continuing to rotate the first rotating column 134 will drive the first rotating tube 136 to rotate, and the first rotating tube 136 will drive the second rotating column 1341 at the top to rotate. The second rotating column 1341 extends out from the inside of the second rotating tube 1361 under the action of the protrusion 138 and the spiral groove 139, and connects the second rotating column 1341 and the second rotating tube 1361 through the protrusion 138 and the spiral groove 139. Next, rotating the first rotating column 134 drives the first rotating tube 136, the second rotating column 1341 and the second rotating tube 1361 to rotate. The second rotating tube 1361 drives the third rotating column 1342 to extend out from the inside of the third rotating tube 1362 under the action of the protrusion 138 and the spiral groove 139. At this time, the distance between the four adjacent resistance heaters 13 is adjusted to the same distance, and the multiple resistance heaters 13 are controlled to be set to different temperatures from bottom to top, so that the formed silicon rod is gradually cooled down.

[0025] like Figures 1 to 7 As shown, a spiral heat-absorbing tube 124 is fixed at the bottom of the clamping seat 123, and a box 2 is fixed on the side of the furnace body 11 away from the control device 1. A heating pot 22 is installed inside the box 2, and heat dissipation fins 128 are installed below the heating pot 22. Among them, the spiral heat absorption tube 124 absorbs the heat of the seed crystal held by the clamping seat 123, and the heat dissipation fins 128 conduct and evaporate the heat. During the seed crystal pulling process, heat from the liquid silicon material is absorbed. At this time, the spiral heat absorption tube 124 absorbs the heat and conducts it to the heat dissipation fins 128. The heat dissipation fins 128 heat the heating pot 22. The polycrystalline silicon particles to be used are placed inside the heating pot 22. The polycrystalline silicon particles are dried by heat, which can preheat the polycrystalline silicon particles and dry their surface moisture, so as to avoid being affected during the melting process.

[0026] like Figures 1 to 7As shown, a water pump 127 is installed on one side of the top of the box 2. A water outlet pipe 126 is fixed to the outer end of the spiral heat absorption pipe 124, and a water inlet pipe 125 is fixed to the inner end of the spiral heat absorption pipe 124. The other end of the water inlet pipe 125 is connected to the water outlet of the water pump 127. The water inlet of the water pump 127 is connected to the water outlet of the heat dissipation fin 128 through a pipe. The other end of the water outlet pipe 126 is connected to the water inlet of the heat dissipation fin 128. An air inlet is opened at the bottom of the box 2, and a cooling fan 21 is installed inside the air inlet. A heat-conducting fluid is injected into the spiral heat absorber 124, the inlet pipe 125, and the outlet pipe 126. When the spiral heat absorber 124 needs to conduct heat, the water pump 127 is started to draw liquid and input it into the inlet pipe 125. The inlet pipe 125 inputs the liquid into the middle of the spiral heat absorber 124 and diffuses it outward through the middle of the inlet pipe 125. At the same time, the liquid inside the spiral heat absorber 124 carries away the heat absorbed by the spiral heat absorber 124 and inputs it into the outlet pipe 126. The outlet pipe 126 inputs the liquid into the heat dissipation fins 128. The heat dissipation fins 128 evaporate the heat of the liquid. The heat can be carried away by the airflow through the cooling fan 21. The airflow carrying heat can heat the heating pot 22 by passing through the bottom of the heating pot 22, thereby preheating the polycrystalline silicon particles inside the heating pot 22.

[0027] like Figures 1 to 8 As shown, a first tilting frame 243 is provided inside the heating pot 22, and a connecting rod 245 is fixed in the middle of the first tilting frame 243. A second motor 242 is provided above the heating pot 22, and the end of the rotating shaft of the second motor 242 is fixedly connected to the top of the connecting rod 245. During the heating process inside the heating pot 22, the particles inside the heating pot 22 will be in a static state. At this time, only the particles close to the inside of the heating pot 22 can be heated well. Starting the second motor 242 drives the connecting rod 245 to rotate, which can drive the first turning frame 243 to rotate inside the heating pot 22. At this time, the first turning frame 243 can turn the particles in contact with the surface of the heating pot 22, so that more particles can come into contact with the surface of the heating pot 22.

[0028] like Figures 1 to 8 As shown, a lifting frame 24 is installed at the bottom of the second motor 242, and a second lifting rod 232 is provided on the side of the lifting frame 24 away from the second motor 242. A support plate 23 is fixed on one side of the housing 2, and the bottom end of the second lifting rod 232 is fixedly connected to the support plate 23. When the preheating is complete and the particles inside the heating pot 22 need to be transferred into the crucible 112, the first tilting frame 243 needs to be separated from the heating pot 22. At this time, the second lifting rod 232 is activated to lift the lifting frame 24. The lifting frame 24 drives the connecting rod 245 to separate the first tilting frame 243 from the inside of the heating pot 22, which makes it easier to remove the heating pot 22 from the inside of the box 2.

[0029] like Figures 1 to 8 As shown, guide holes 231 are provided on both sides of the support plate 23, and sliders are provided on both sides of the lifting frame 24. The sliders are slidably connected inside the guide holes 231. When the lifting frame 24 is raised, it slides inside the guide hole 231 through the sliders on both sides, which can maintain the stability of the lifting frame 24 during lifting.

[0030] like Figures 1 to 8 As shown, a bent section is provided above the guide hole 231, and the slider can slide inside the bent section; When the slider slides from the guide hole 231 into the bent section, the lifting frame 24 is driven by the slider to move in the direction of the second lifting rod 232; When the first tilting rack 243 is raised, in order not to block the heating pot 22, a bent section is set above the guide hole 231. When the slider slides to the bent section, it will drive the slider to move the lifting rack 24 towards the direction of the second lifting rod 232. At this time, the lifting rack 24 drives the first tilting rack 243 to move into the support plate 23, so that the first tilting rack 243 will not block the path of taking out the heating pot 22.

[0031] like Figures 1 to 8 As shown, a guide rail 241 is fixed to the bottom end of the lifting frame 24, and a guide block 233 is fixed to the top end of the second lifting rod 232. The guide block 233 is slidably connected to the outside of the guide rail 241. When the lifting frame 24 slides inside the support plate 23, in order to maintain the connection between the second lifting rod 232 and the lifting frame 24, a guide block 233 is provided that can slide outside the guide rail 241. At this time, the guide rail 241 and the guide block 233 can keep the lifting frame 24 in a horizontal state when it moves towards the second lifting rod 232.

[0032] like Figures 1 to 9 As shown, a pair of second tilting frames 244 are rotatably connected inside the first tilting frame 243. One end of the rotating shaft of the second tilting frame 244 is rotatably connected inside the connecting rod 245. A rotating rod 246 is rotatably connected inside the connecting rod 245. A gear is fixed at the bottom end of the rotating rod 246. A gear is fixed at the end of the second tilting frame 244. The gear and the gear are meshed together. A first gear 248 is fixed at the top end of the rotating rod 246. A second gear 249 is meshed with one side of the first gear 248. The second gear 249 is rotatably connected inside the connecting rod 245. The other side of the second gear 249 extends out from the outside of the connecting rod 245. A toothed ring 247 is fixed near the bottom end of the lifting frame 245. The toothed ring 247 and the second gear 249 are meshed together. When the first turning rack 243 turns the material inside the heating pot 22, the particles in the middle of the heating pot 22 are not turned. Therefore, a second turning rack 244 is set up. When the connecting rod 245 rotates, it drives the first gear 248 and the second gear 249 to rotate. When the second gear 249 rotates, it rotates inside the gear ring 247. The second gear 249 is driven to rotate by the gear ring 247. The second gear 249 drives the first gear 248 to rotate, thereby causing the rotating rod 246 to drive the gear plate to rotate. The gear plate drives the second turning rack 244 to rotate through the two gears to turn the material in the middle of the heating pot 22, which can achieve better heating inside the heating pot 22.

[0033] The foregoing has shown and described 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 to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A single-crystal furnace with a multi-stage heating structure, characterized in that: The device includes a control unit, a furnace body fixed to one side of the control unit, a support frame installed at the top of the control unit, a crystal pulling assembly connected to the side of the support frame near the furnace body via a lifting device, a first lifting rod inside the crystal pulling assembly, a clamping seat fixed at the bottom of the first lifting rod, the bottom of the clamping seat being able to clamp the seed crystal, an isolation tube fixed inside the furnace body, a crucible inside the isolation tube, a rotating assembly installed at the bottom of the furnace body, and the end of the rotating shaft of the rotating assembly being fixedly connected to the bottom of the crucible. The isolation tube is equipped with multiple resistance heaters. There is a gap between two adjacent resistance heaters. Multiple temperature sensors are installed at equal intervals on the top of each resistance heater. The height of the temperature sensors is smaller than the size of the gap between the resistance heaters. The first motor is installed on both sides of the bottom of the furnace body. Specifically, when the first motor rotates forward, it increases the distance between the resistance heaters; when the first motor rotates in reverse, it decreases the distance between the resistance heaters.

2. A single crystal furnace with a multi-segment heating structure according to claim 2, characterized in that: Fixed plates are fixed to both sides of the bottom resistance heater, and the fixed plates are fixedly connected to the isolation tube. The end of the shaft of the first motor passes through the inside of the fixed plate, and a rotating column is fixed to the end of the shaft. Top connecting plates are fixed to both sides of the top resistance heater. A rotating tube is fixed to one side of the top connecting plate. A movable plate is set below the top connecting plate. The movable plate is fixedly connected to one of the resistance heaters. A rotating tube is rotatably connected to one side of the movable plate. A rotating column is fixed to the top of the rotating tube and inserted into the rotating tube. A movable plate is provided above the fixed plate, and the movable plate is also fixedly connected to one of the resistance heaters. A rotating tube is rotatably connected to one side of the movable plate. A rotating column is fixed to the top of the rotating tube. The rotating column is inserted inside the rotating tube and the rotating column is inserted inside the rotating tube. A spiral groove is provided on the outer side of the rotating column, the rotating column, and the rotating column. A limit groove is provided at the top and bottom of the spiral groove. Protrusions are fixed on both sides inside the rotating tube, the rotating tube, and the rotating tube. The protrusions are slidably connected inside the spiral groove.

3. A single crystal furnace with a multi-segment heating structure according to claim 3, characterized in that: A spiral heat-absorbing tube is fixed at the bottom of the clamping seat. A box is fixed on the side of the furnace body away from the control device. A heating pot is installed inside the box, and heat dissipation fins are installed below the heating pot. The spiral heat absorber absorbs the heat from the seed crystal held by the clamping seat, while the heat dissipation fins conduct and dissipate the heat.

4. A single crystal furnace with a multi-segment heating structure according to claim 1, characterized in that: A water pump is installed on one side of the top of the enclosure. A water outlet pipe is fixed to the outer end of the spiral heat absorption tube, and a water inlet pipe is fixed to the inner end of the spiral heat absorption tube. The other end of the water inlet pipe is connected to the water outlet of the water pump. The water inlet of the water pump is connected to the water outlet of the heat dissipation fins through a pipe. The other end of the water outlet pipe is connected to the water inlet of the heat dissipation fins. An air inlet is opened at the bottom of the enclosure, and a cooling fan is installed inside the air inlet.

5. A single crystal furnace with a multi-segment heating structure according to claim 5, characterized in that: The heating pot is equipped with a first tilting rack inside, and a connecting rod is fixed in the middle of the first tilting rack. A second motor is installed above the heating pot, and the end of the rotating shaft of the second motor is fixedly connected to the top of the connecting rod.

6. A single crystal furnace with a multi-segment heating structure according to claim 1, characterized in that: A lifting frame is installed at the bottom of the second motor. A second lifting rod is installed on the side of the lifting frame away from the second motor. A support plate is fixed on one side of the housing. The bottom end of the second lifting rod is fixedly connected to the support plate.

7. A single crystal furnace with a multi-segment heating structure according to claim 1, characterized in that: Guide holes are provided on both sides of the support plate, and sliders are provided on both sides of the lifting frame. The sliders are slidably connected inside the guide holes.

8. A single crystal furnace with a multi-segment heating structure according to claim 1, characterized in that: A bent section is provided above the guide hole, and the slider can slide inside the bent section; When the slider slides from the guide hole into the bent section, the lifting frame is driven by the slider to move towards the direction of the second lifting rod.

9. A single crystal furnace with a multi-segment heating structure according to claim 1, characterized in that: The bottom of the lifting frame is fixed with a guide rail, and the top of the second lifting rod is fixed with a guide block, which is slidably connected to the outside of the guide rail.

10. A single crystal furnace with a multi-segment heating structure according to claim 10, characterized in that: A pair of second tilting frames are rotatably connected inside the first tilting frame. One end of the rotating shaft of the second tilting frame is rotatably connected inside the connecting rod. A rotating rod is rotatably connected inside the connecting rod. A gear is fixed at the bottom end of the rotating rod. A gear is fixed at the end of the second tilting frame. The gear and the gear are meshed together. A first gear is fixed at the top end of the rotating rod. A second gear is meshed with one side of the first gear. The second gear is rotatably connected inside the connecting rod. The other side of the second gear extends out from the outside of the connecting rod. A toothed ring is fixed near the bottom end of the lifting frame near the connecting rod. The toothed ring and the second gear are meshed together.

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