Seed crystal length measuring device and crystal growing apparatus

Abstract

The utility model discloses a kind of seed crystal length measuring device and crystal growth device, seed crystal length measuring device includes: upper furnace cylinder, seed crystal shaft, seed crystal fixture and measuring component, measuring component includes range finder and test stand, in test position, test stand is located below seed crystal fixture and is oppositely arranged with seed crystal fixture, test stand includes mounting bracket and the limiting plate and movable plate of being arranged in mounting bracket, movable plate is located the downside of limiting plate, range finder is used to measure the distance of range finder and the upper surface of movable plate along up-down direction, movable plate is movable between first position and second position, movable plate is suitable to be pushed down from first position to second position by seed crystal on seed crystal fixture, in second position, seed crystal fixture and the upper surface of limiting plate abut. According to the seed crystal length measuring device of the utility model, the length of seed crystal can be measured without opening sub-chamber, measurement accuracy is high and can reduce the risk of sub-chamber air leakage in seed crystal length measurement process.

Description

Technical Field

[0001] This utility model relates to the field of crystal growth technology, and in particular to a seed crystal length measuring device and a crystal growth device. Background Technology

[0002] In the Czochralski method of monocrystalline silicon crystal pulling, the liquid gate distance (i.e., the vertical distance between the lower opening of the guide tube and the surface of the molten silicon) directly affects the crystal growth rate and quality. Therefore, the measurement of the liquid gate distance is crucial. The liquid gate distance can be obtained by measuring the length of the exposed portion of the seed crystal after it is placed in the seed crystal fixture. However, the accuracy of seed crystal length measurement in related technologies is not high, and there is a risk of furnace leakage, which directly affects the growth rate and quality of the seed crystal. Utility Model Content

[0003] The first aspect of this utility model proposes a seed crystal length measuring device, which has the advantages of high measurement accuracy and can avoid air leakage in the auxiliary furnace chamber during the measurement process.

[0004] According to a first aspect of the present invention, a seed crystal length measuring device includes: an upper furnace cylinder having an auxiliary furnace chamber; a seed crystal shaft, which is vertically and vertically disposed in the upper furnace cylinder, the lower end of which is located in the auxiliary furnace chamber and is provided with a seed crystal clamp for holding a seed crystal; and a measuring assembly including a rangefinder and a testing frame, wherein the rangefinder is installed in the upper furnace cylinder and located in the auxiliary furnace chamber, the rangefinder being located above or below the testing frame, and the testing frame being movable between a testing position and a clearance position. In the testing position, the testing frame is located in the auxiliary furnace chamber and is located below and opposite to the seed crystal clamp; in the clearance position... The test frame is located outside the auxiliary furnace; wherein, the test frame includes a mounting bracket and a limiting plate and a movable plate disposed on the mounting bracket, the movable plate being located below the limiting plate, the rangefinder being used to measure the distance between the rangefinder and the upper surface of the movable plate in the vertical direction, the movable plate being movable relative to the mounting bracket in the vertical direction between a first position and a second position, the first position being above the second position, the movable plate being adapted to be pushed downward from the first position to the second position by a seed crystal on the seed crystal clamp, in the first position, the seed crystal clamp being spaced apart from the limiting plate, and in the second position, the seed crystal clamp abutting against the upper surface of the limiting plate.

[0005] According to the seed crystal length measuring device of the first aspect of this utility model, by setting the rangefinder and the test frame located at the test position in the auxiliary furnace chamber, the length of the part of the seed crystal extending downward from the seed crystal clamp can be measured without opening the auxiliary furnace chamber through the cooperation of the seed crystal shaft, the seed crystal clamp, the seed crystal, the rangefinder and the test frame. This can improve the accuracy of seed crystal length measurement and reduce the risk of air leakage in the auxiliary furnace chamber during the seed crystal length measurement process. This can avoid the impact of air leakage in the auxiliary furnace chamber on the seed crystal growth thermal field, and help improve the growth efficiency and quality of the crystal.

[0006] According to some embodiments of this utility model, a first clearance hole is formed on the limiting plate in the vertical direction. At the test position, the projection of the seed crystal on the horizontal plane is the first projection, and the projection of the first clearance hole on the horizontal plane is the second projection. The first projection is located within the second projection. A second clearance hole is formed on the limiting plate in the vertical direction. The second clearance hole is spaced apart from the first clearance hole. At the test position, the projection of the rangefinder on the horizontal plane is the third projection, and the projection of the second clearance hole on the horizontal plane is the fourth projection. The third projection is located within the fourth projection.

[0007] According to some embodiments of the present invention, at the test position, the limiting plate is in a grounded state, the seed crystal fixture is in a powered state, and the measuring component further includes a detection module, which is used to detect the voltage of the seed crystal fixture.

[0008] According to some embodiments of the present invention, the measuring component further includes a reset mechanism, the reset mechanism including an electromagnetic plate disposed on the lower side of the movable plate, at least a portion of the movable plate being a magnet and located in the magnetic field generated by the electromagnetic plate, the electromagnetic plate having an upward magnetic force on the movable plate.

[0009] According to some embodiments of this utility model, a pressure sensor is provided at the bottom of the movable plate. The pressure sensor is used to detect the downward pressure of the movable plate. The pressure value F' of the pressure sensor satisfies: F'=M1*G+M2*G+ΔF, 0.1M3*G<ΔF≤0.5M3*G; where M1 is the weight of the movable plate, M2 is the weight of the electromagnetic plate, M3 is the weight of the seed crystal 200, and G is the gravitational acceleration.

[0010] According to some embodiments of the present invention, a receiving chamber is provided on the outer periphery of the upper furnace cylinder, and a receiving cavity is formed in the receiving chamber. A connecting port is provided on the peripheral wall of the upper furnace cylinder, and the receiving cavity is connected to the auxiliary furnace chamber through the connecting port. In the avoidance position, the test frame is located in the receiving cavity.

[0011] According to some embodiments of the present invention, a switch door is provided at the connection port, and the switch door is used to open or close the connection port.

[0012] According to some embodiments of the present invention, the seed crystal length measuring device further includes a support rod, which is movable between a support position and a retracted position. In the support position, the support rod extends into the auxiliary furnace chamber and cooperates with the test frame to hold the test frame in the test position. In the retracted position, the support rod is located outside the auxiliary furnace chamber.

[0013] According to some embodiments of the present invention, a mating slot is formed on the outer peripheral surface of the test frame, and the support rod located at the support position is detachably plugged into the test frame located at the test position.

[0014] According to some embodiments of the present invention, the measuring assembly further includes a first driving mechanism, which is used to drive the test frame to move between the test position and the avoidance position. The first driving mechanism and the supporting rod are located on opposite sides of the test frame in the horizontal direction.

[0015] The second aspect of this utility model proposes a crystal growth apparatus.

[0016] A crystal growth apparatus according to a second aspect of the present invention includes: the above-mentioned seed crystal length measuring device; a furnace body disposed on the lower side of the upper furnace cylinder, wherein a main furnace chamber adapted to communicate with the auxiliary furnace chamber is formed within the furnace body; and a crucible for holding molten molten material and located within the main furnace chamber.

[0017] According to the crystal growth apparatus of the second aspect of this utility model, by setting the rangefinder and the test frame located at the test position in the auxiliary furnace chamber, the length of the portion of the seed crystal extending downward from the seed crystal clamp can be measured without opening the auxiliary furnace chamber through the cooperation of the seed crystal shaft, the seed crystal clamp, the seed crystal, the rangefinder and the test frame. This can improve the accuracy of the seed crystal length measurement and reduce the risk of air leakage in the auxiliary furnace chamber during the seed crystal length measurement process. This can avoid the impact of air leakage in the auxiliary furnace chamber on the seed crystal growth thermal field, and help improve the growth efficiency and quality of the crystal.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a seed crystal length measuring device according to an embodiment of the present utility model, wherein the test frame is located in an avoidance position;

[0020] Figure 2This is a schematic diagram of a seed crystal length measuring device according to an embodiment of the present utility model, wherein the test frame is located at the test position and the movable plate is located at the first position;

[0021] Figure 3 This is a schematic diagram of a seed crystal length measuring device according to an embodiment of the present utility model, wherein the test frame is located at the test position and the movable plate is located at the second position;

[0022] Figure 4 yes Figure 3 Enlarged view of region A in the middle;

[0023] Figure 5 This is a schematic diagram of the test frame of the seed crystal length measuring device according to an embodiment of the present utility model;

[0024] Figure 6 This is a top view of the limiting plate of the seed crystal length measuring device according to an embodiment of the present utility model;

[0025] Figure 7 This is a schematic diagram of the structure of the movable plate of the seed crystal length measuring device according to an embodiment of the present utility model;

[0026] Figure 8 This is a top view of the movable plate of the seed crystal length measuring device according to an embodiment of the present utility model.

[0027] Figure label:

[0028] 100. Seed crystal length measuring device;

[0029] 1. Upper furnace cylinder; 11. Auxiliary furnace chamber; 12. Connecting port; 2. Seed crystal shaft; 3. Seed crystal clamp;

[0030] 4. Measuring components; 41. Rangefinder; 42. Test frame; 421. Mounting bracket; 4211. Connecting column; 422. Limiting plate; 4221. First clearance hole; 4222. Second clearance hole; 4223. Connecting hole; 4224. Outer ring; 4225. Center; 4226. Connecting part; 423. Movable plate; 4231. Silicon material layer; 4232. Permanent magnet layer; 4233. Guide groove; 424. Electromagnetic plate; 425. Reinforcing plate; 43. First drive mechanism; 44. Connecting bracket;

[0031] 5. Receiving compartment; 51. Receiving cavity; 52. Opening / closing door; 53. Receiving cavity; 6. Support rod; 7. Isolation valve;

[0032] 200. Seed crystal. Detailed Implementation

[0033] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this utility model, and should not be construed as limiting this utility model.

[0034] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the applicability of other processes and / or the use of other materials.

[0035] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0036] In the description of this utility model, "first feature" and "second feature" may include one or more of the features.

[0037] In the description of this utility model, "multiple" means two or more.

[0038] In the description of this utility model, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or it may include the first and second features not being in direct contact but being in contact through another feature between them.

[0039] In the description of this utility model, the terms "above", "over" and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0040] The seed crystal length measuring device 100 according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0041] like Figures 1 to 4 As shown, the seed crystal length measuring device 100 according to an embodiment of the present invention includes: an upper furnace cylinder 1, a seed crystal shaft 2, a seed crystal clamp 3, and a measuring component 4. The upper furnace cylinder 1 has a secondary furnace chamber 11. The seed crystal shaft 2 is vertically and vertically mounted on the upper furnace cylinder 1. The lower end of the seed crystal shaft 2 is located in the secondary furnace chamber 11 and is provided with a seed crystal clamp 3. The seed crystal clamp 3 is used to clamp the seed crystal 200. Thus, the seed crystal shaft 2 can drive the seed crystal clamp 3 to move up and down, thereby moving the seed crystal 200 on the seed crystal clamp 3 to meet the growth requirements of the seed crystal 200.

[0042] The measuring component 4 includes a rangefinder 41 and a test frame 42. The rangefinder 41 is installed in the upper furnace cylinder 1 and located inside the auxiliary furnace chamber 11. The rangefinder 41 is located above or below the test frame 42. The test frame 42 is movable between a test position and a clearance position. In the test position, the test frame 42 is located inside the auxiliary furnace chamber 11 and is positioned below and opposite to the seed crystal clamp 3. In the clearance position, the test frame 42 is located outside the auxiliary furnace chamber 11. The test frame 42 includes a mounting bracket 421 and a limiting plate 422 and a movable plate 422 disposed on the mounting bracket 421. 23. The movable plate 423 is located below the limiting plate 422. The rangefinder 41 is used to measure the distance between the rangefinder 41 and the upper surface of the movable plate 423 in the vertical direction. The movable plate 423 is movable between a first position and a second position in the vertical direction relative to the mounting bracket 421. The first position is located above the second position. The movable plate 423 is adapted to be pushed down from the first position to the second position by the seed crystal 200 on the seed crystal clamp 3. In the first position, the seed crystal clamp 3 is spaced apart from the limiting plate 422. In the second position, the seed crystal clamp 3 abuts against the upper surface of the limiting plate 422.

[0043] Specifically, the test frame 42 is usually in a clearance position to avoid affecting the vertical movement of the seed crystal 200. The measurement of the length of the seed crystal 200 specifically involves measuring the length of the portion of the seed crystal 200 extending downwards from the seed crystal clamp 3. When measuring the length of the portion of the seed crystal 200 extending downwards from the seed crystal clamp 3 (defined as H0 for ease of description) using the measuring component 4, the seed crystal clamp 3 can first be driven by the seed crystal shaft 2 to move the seed crystal 200 upwards until the seed crystal 200 is completely above the test frame 42. Then, the test frame 42 is controlled to move from the clearance position to the test position, so that the seed crystal 200 and the movable plate 423 are set opposite each other in the vertical direction. That is, at this time, the projection of the seed crystal 200 on the horizontal plane is located within the projection of the movable plate 423 on the horizontal plane. The movable plate 423 is in the first position. The distance between the distance measuring instrument 41 and the upper surface of the movable plate 423 is measured by the distance measuring instrument 41 and recorded as H1.

[0044] Then, the seed crystal shaft 2 drives the seed crystal clamp 3 to move downwards. The seed crystal 200 gradually approaches the movable plate 423. After the seed crystal 200 contacts the movable plate 423, it pushes the movable plate 423 downwards until the seed crystal clamp 3 abuts against the upper surface of the limiting plate 422. The limiting plate 422 prevents the seed crystal clamp 3 from moving further downwards. At this time, the movable plate 423 is in the second position. The distance between the distance measuring instrument 41 and the upper surface of the movable plate 423 is measured by the distance measuring instrument 41 and recorded as H2. Therefore, the displacement distance of the movable plate 423 from the first position to the second position pushed by the seed crystal 200 is: H2-H1, that is, the vertical distance between the upper surface of the movable plate 423 in the first position and the upper surface of the movable plate 423 in the second position.

[0045] It should be noted that the length of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3 is equal to the vertical distance between the upper surface of the movable plate 423 in the second position and the upper surface of the limiting plate 422. This vertical distance is equal to the vertical distance between the upper surface of the movable plate 423 in the first position and the upper surface of the movable plate 423 in the second position (H2-H1) plus the vertical distance between the upper surface of the movable plate 423 in the first position and the upper surface of the limiting plate 422. It can be understood that the distance between the upper surface of the movable plate 423 in the first position and the upper surface of the limiting plate 422 is a known fixed parameter of the test fixture 42, denoted as H3 for ease of description. Therefore, the length H0 of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3 is H2-H1+H3. Since the test frame 42 and the rangefinder 41 located at the test position are both located inside the auxiliary furnace chamber 11, the length of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3 can be measured without opening the auxiliary furnace chamber 11. Furthermore, H1 and H2 are both obtained by the rangefinder 41, which has high accuracy, and H3 is a fixed value, thereby improving the accuracy of measuring the length of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3.

[0046] Therefore, by placing the rangefinder 41 and the test frame 42 located at the test position inside the auxiliary furnace chamber 11, and through the cooperation of the seed crystal shaft 2, seed crystal fixture 3, seed crystal 200, rangefinder 41 and test frame 42, the length of the portion of the seed crystal 200 extending downward from the seed crystal fixture 3 can be measured without opening the auxiliary furnace chamber 11. This can improve the accuracy of the seed crystal 200 length measurement and reduce the risk of air leakage in the auxiliary furnace chamber 11 during the seed crystal 200 length measurement process. This can avoid the impact of air leakage in the auxiliary furnace chamber 11 on the growth thermal field of the seed crystal 200, and help improve the growth efficiency and quality of the crystal.

[0047] According to the seed crystal length measuring device 100 of this utility model embodiment, by setting the rangefinder 41 and the test frame 42 located at the test position in the auxiliary furnace chamber 11, the length of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3 can be measured without opening the auxiliary furnace chamber 11 through the cooperation of the seed crystal shaft 2, the seed crystal clamp 3, the seed crystal 200, the rangefinder 41 and the test frame 42. This can improve the accuracy of the seed crystal 200 length measurement and reduce the risk of air leakage in the auxiliary furnace chamber 11 during the seed crystal 200 length measurement process. This can avoid the impact of air leakage in the auxiliary furnace chamber 11 on the growth thermal field of the seed crystal 200, which is conducive to improving the growth efficiency and quality of the crystal.

[0048] In some embodiments, the rangefinder 41 is a laser rangefinder 41. The laser rangefinder 41 emits a laser to the upper surface of the movable plate 423, and by obtaining the time taken for the laser to be emitted to the movable plate 423 and return to the laser rangefinder 41, the distance between the laser rangefinder 41 and the upper surface of the movable plate 423 can be calculated, which can ensure the ranging accuracy and efficiency of the rangefinder 41.

[0049] In some embodiments, the rangefinder 41 is located on the top wall of the auxiliary furnace chamber 11 and on the outer periphery of the seed crystal fixture 3, which can prevent the rangefinder 41 from affecting the vertical movement of the seed crystal 200, so that the rangefinder 41 can directly detect the distance between the rangefinder 41 and the upper surface of the movable plate 423.

[0050] According to some embodiments of this utility model, such as Figure 6 As shown, a first clearance hole 4221 extending vertically is formed on the limiting plate 422. In the test position, the projection of the seed crystal 200 on the horizontal plane is the first projection, and the projection of the first clearance hole 4221 on the horizontal plane is the second projection. The first projection is located within the second projection. Therefore, when the seed crystal shaft 2 drives the seed crystal 200 downward, the lower end of the seed crystal 200 can pass through the first clearance hole 4221 to contact the movable plate 423 located below the limiting plate 422. When the seed crystal 200 passes through the first clearance hole 4221, the outer peripheral surface of the seed crystal 200 is separated from the inner peripheral surface of the seed crystal 200, thereby preventing the limiting plate 422 from blocking the downward movement of the seed crystal 200.

[0051] That is, the first clearance hole 4221 provides clearance space for the seed crystal 200 to contact the movable plate 423, thereby ensuring that the seed crystal 200 can stably contact the movable plate 423 and push the movable plate 423 downward to the second position. It should be noted that the size of the first clearance hole 4221 is smaller than the size of the seed crystal clamp 3, thereby preventing the seed crystal clamp 3 from passing through the first clearance hole 4221. That is, in the second position, the seed crystal clamp 3 rests on the portion of the upper surface of the limiting plate 422 located on the outer periphery of the first clearance hole 4221, so as to ensure the limiting effect of the limiting plate 422 on the seed crystal clamp 3.

[0052] According to some embodiments of this utility model, such as Figure 6 As shown, a second clearance hole 4222 is formed on the limiting plate 422, extending vertically. The second clearance hole 4222 is spaced apart from the first clearance hole 4221. For example, the second clearance hole 4222 and the first clearance hole 4221 are arranged horizontally. At the test position, the projection of the rangefinder 41 on the horizontal plane is the third projection, and the projection of the second clearance hole 4222 on the horizontal plane is the fourth projection. The third projection is located within the fourth projection. In other words, by setting the second clearance hole 4222, the limiting plate 422 can be prevented from obstructing the rangefinder 41 from measuring the upper surface of the movable plate 423. The test light emitted by the rangefinder 41, such as a laser rangefinder 41, can be irradiated onto the upper surface of the movable plate 423 through the second clearance hole 4222. The specific measurement area is the part of the upper surface of the movable plate 423 opposite to the second clearance hole 4222, so as to obtain the distance between the rangefinder 41 and the upper surface of the movable plate 423 in the vertical direction.

[0053] According to some embodiments of this utility model, such as Figure 5 As shown, in the first position, the upper surface of the movable plate 423 abuts against the lower surface of the limiting plate 422. That is, in the first position, the distance between the upper surface of the movable plate 423 and the upper surface of the limiting plate 422 is the thickness of the limiting plate 422 in the vertical direction. This makes the data on the distance H3 between the upper surface of the movable plate 423 and the upper surface of the limiting plate 422 more accurate and easier to obtain, thereby improving the accuracy of the seed crystal 200 length calculation result.

[0054] According to some embodiments of this utility model, such as Figure 7 As shown, the upper surface of the movable plate 423 is provided with a silicon material layer 4231. The seed crystal 200 is made of silicon. During the measurement of the length of the seed crystal 200, since the seed crystal 200 needs to contact the upper surface of the movable plate 423, by providing a silicon material layer 4231 of the same material as the seed crystal 200 on the upper surface of the movable plate 423, contamination of the seed crystal 200 by the movable plate 423 can be avoided, thus ensuring the purity of the seed crystal 200.

[0055] According to some embodiments of the present invention, in the first position, such as Figure 5 and Figure 7 As shown, the upper surface of the movable plate 423 abuts against the lower surface of the limiting plate 422, and a silicon material layer 4231 is provided on the upper surface of the movable plate 423. This improves the accuracy of the seed crystal 200 length calculation and prevents the movable plate 423 from contaminating the seed crystal 200, thus ensuring the purity of the seed crystal 200.

[0056] According to some embodiments of this utility model, at the test position, the limiting plate 422 is grounded, the seed crystal 200 chuck is energized, and the measuring component 4 also includes a detection module for detecting the voltage of the seed crystal 200 chuck. Since the limiting plate 422 is grounded, when the movable plate 423 moves to the second position and the seed crystal 200 chuck contacts the limiting plate 422, the voltage at the seed crystal 200 chuck returns to zero. Therefore, when the detection module detects that the voltage of the seed crystal 200 chuck has returned to zero, it indicates that the seed crystal 200 chuck is in contact with the limiting plate 422, and the movable plate 423 has moved to the second position. This allows the seed crystal shaft 2 to stop moving downwards. If the detection module is electrically connected to the drive module of the seed crystal shaft 2, when the detection module detects that the voltage of the seed crystal 200 chuck has returned to zero, the drive module receives the signal and stops driving the seed crystal shaft 2 to move downwards, thus avoiding excessive pressure between the seed crystal 200 chuck and the limiting plate 422 and preventing damage. This improves the safety of seed crystal 200 length measurement.

[0057] According to some embodiments of this utility model, the measuring component 4 further includes a reset mechanism, which includes an electromagnetic plate 424 disposed below the movable plate 423. At least a portion of the movable plate 423 is a magnet and is located in the magnetic field generated by the electromagnetic plate 424. The electromagnetic plate 424 exerts an upward magnetic force on the movable plate 423. That is, after the electromagnetic plate 424 is energized, it generates a magnetic field that pushes the movable plate 423 upward to a first position. The strength of the magnetic field generated by the electromagnetic plate 424 can be controlled by adjusting the current connected to the electromagnetic plate 424, thereby adjusting the upward thrust of the electromagnetic plate 424 on the movable plate 423. Therefore, the flexibility of adjusting the upward thrust of the electromagnetic plate 424 on the movable plate 423 can be improved. Thus, during the process of the movable plate 423 being pushed downward by the seed crystal 200, the interaction force between the movable plate 423 and the seed crystal 200 can be reduced by reducing the upward thrust of the electromagnetic plate 424 on the movable plate 423, thereby preventing damage to the seed crystal 200. In addition, the electromagnetic plate 424 generates magnetic force to push the movable plate 423 upward, which can prevent mechanical mechanisms such as elastic parts from failing to reset due to fatigue after long-term use, thereby ensuring the reset accuracy of the movable plate 423.

[0058] In a specific example, such as Figure 7 As shown, the movable plate 423 includes a silicon material layer 4231 and a permanent magnet layer 4232 stacked in the vertical direction. The silicon material layer 4231 is disposed on the upper side of the permanent magnet layer 4232. The permanent magnet layer 4232 is made of permanent magnet, which can ensure the magnetic force of the movable plate 423.

[0059] According to some embodiments of this utility model, a pressure sensor (not shown in the figure) is provided at the bottom of the movable plate 423. The pressure sensor is used to detect the downward pressure of the movable plate 423. The pressure value F' of the pressure sensor satisfies: F'=M1*G+M2*G+ΔF, 0.1M3*G<ΔF≤0.5M3*G; where M1 is the weight of the movable plate 423, M2 is the weight of the electromagnetic plate 424, M3 is the weight of the seed crystal 200, and G is the gravitational acceleration. In other words, the pressure exerted by the movable plate 423 on the pressure sensor is controlled between M1*G+M2*G+0.1M3*G (excluding M1*G+M2*G+0.1M3*G) and M1*G+M2*G+0.5M3*G (including M1*G+M2*G+0.5M3*G). This avoids excessive pressure exerted by the movable plate 423 on the pressure sensor, thereby reducing the interaction force between the movable plate 423 and the seed crystal 200, and preventing the seed crystal 200 from breaking after being squeezed.

[0060] Before the seed crystal 200 comes into contact with the movable plate 423, the pressure value F of the pressure sensor can be controlled at F = M1*G + M2*G + 0.1M3*G by adjusting the current, so as to ensure the magnetic force of the electromagnetic plate 424 on the movable plate 423.

[0061] In some embodiments, such as Figures 5 to 8 As shown, the mounting bracket 421 includes multiple connecting posts 4211 extending vertically. These posts are evenly spaced along the circumference of the limiting plate 422. Both the limiting plate 422 and the movable plate 423 are circular. The limiting plate 422 is connected to the upper ends of the connecting posts 4211. The limiting plate 422 has multiple connecting holes 4223 corresponding to the connecting posts 4211. The first clearance hole 4221 is located at the center of the limiting plate 422. Therefore, the force exerted on the test frame 42 by the seed crystal clamp 3 and the seed crystal 200 is concentrated at the center of the test frame 42 in the horizontal direction, resulting in a more uniform force distribution on the test frame 42 and ensuring its structural stability. Specifically, the limiting plate 422 includes an outer ring portion 4224 and a central portion 4225. The outer ring portion 4224 is located on the outer periphery of the central portion 4225 and is formed into a ring. A connecting hole 4223 is provided on the outer ring portion 4224, and a first clearance hole 4221 is provided on the central portion 4225. A plurality of connecting portions 4226 are connected between the outer ring portion 4224 and the central portion 4225. The plurality of connecting portions 4226 are arranged at intervals along the circumference of the central portion 4225. The plurality of connecting portions 4226 correspond one-to-one with the plurality of connecting holes 4223. The end of the connecting hole 4223 away from the central portion 4225 extends toward the corresponding connecting hole 4223. The central portion 4225, the outer ring portion 4224 and the plurality of connecting portions 4226 together define the second clearance hole 4222.

[0062] In addition, the outer periphery of the movable plate 423 is provided with multiple guide grooves 4233, and multiple connecting posts 4211 are correspondingly inserted into the multiple guide grooves 4233 to improve the stability of the movable plate 423 sliding up and down relative to the multiple connecting posts 4211. The electromagnetic plate 424 is connected to the lower end of the multiple connecting posts 4211. The test frame 42 also includes a reinforcing plate 425, which is connected to the multiple connecting posts 4211 and located in the middle of the connecting posts 4211 in the vertical direction, so as to improve the overall structural stability of the test frame 42.

[0063] According to some embodiments of this utility model, such as Figures 1 to 3 As shown, a receiving chamber 5 is provided on the outer periphery of the upper furnace cylinder 1, and a receiving cavity 51 is formed inside the receiving chamber 5. A connecting port 12 is provided on the peripheral wall of the upper furnace cylinder 1. The receiving cavity 51 is connected to the auxiliary furnace chamber 11 through the connecting port 12. In the avoidance position, the test frame 42 is located inside the receiving cavity 51. That is to say, the receiving cavity 51 is located on the outer periphery of the auxiliary furnace chamber 11. When it is necessary to measure the length of the seed crystal 200, the test frame 42 located in the receiving cavity 51 enters the auxiliary furnace chamber 11 through the connecting port 12 to cooperate with the rangefinder 41 and the seed crystal 200 to achieve distance measurement. After the length of the seed crystal 200 is measured, the test frame 42 located in the auxiliary furnace chamber 11 returns to the receiving cavity 51 through the connecting port 12 to avoid the test frame 42 interfering with the vertical movement of the seed crystal 200. Therefore, by setting up a receiving cavity 51 that is connected to the auxiliary furnace chamber 11 and located on the outer periphery of the auxiliary furnace chamber 11, the test frame 42 in the avoidance position can be accommodated to prevent the test frame 42 from interfering with the movement of the seed crystal 200, while avoiding communication between the auxiliary furnace chamber 11 and the external space, so as to ensure the sealing of the auxiliary furnace chamber 11 during the seed crystal 200 length measurement process.

[0064] According to some embodiments of this utility model, such as Figure 3 and Figure 4 As shown, a switch door 52 is provided at the connection port 12, which is used to open or close the connection port 12. Thus, closing the connection port 12 by switching door 52 can cut off the connection between the auxiliary furnace chamber 11 and the receiving cavity 51, thereby reducing the influence of the receiving cavity 51 on the growth thermal field of the seed crystal 200. In addition, it can prevent impurities or high-temperature gases from entering the receiving cavity 51 during the growth of the seed crystal 200 and contaminating or damaging the test rack 42, so as to ensure the safety of the test rack 42 when it is in the avoidance position.

[0065] In some embodiments, such as Figure 3 As shown, the receiving chamber 5 also forms a receiving cavity 53, which is located at the top of the receiving cavity 51 and at one end of the receiving cavity 51 near the auxiliary furnace chamber 11. The receiving cavity 53 opens downward and communicates with the receiving cavity 51. The opening and closing door 52 is provided in the receiving cavity 53 in a way that can extend or retract, so as to avoid the opening and closing door 52 interfering with the movement of the test frame 42.

[0066] According to some embodiments of this utility model, such as Figure 2 and Figure 3 As shown, the seed crystal length measuring device 100 also includes a support rod 6, which is movable between a supported position and a retracted position. In the supported position, the support rod 6 extends into the auxiliary furnace chamber 11 and cooperates with the test frame 42 to hold the test frame 42 in the test position. In the retracted position, the support rod 6 is located outside the auxiliary furnace chamber 11. Thus, the support rod 6 in the supported position can stably hold the test frame 42 in the test position, thereby preventing the test frame 42 from shaking and affecting the measurement of the seed crystal 200 length, and thus improving the accuracy of the seed crystal 200 length measurement. Furthermore, the support rod 6 in the retracted position is located outside the auxiliary furnace chamber 11, which can prevent the support rod 6 from interfering with the vertical movement of the seed crystal 200.

[0067] According to some embodiments of this utility model, a mating slot (not shown in the figure) is formed on the outer peripheral surface of the test frame 42, and the support rod 6 located in the support position is detachably plugged into the test frame 42 located in the test position. That is, after the test frame 42 moves to the test position, the support rod 6 moves radially along the upper furnace cylinder 1 until the support rod 6 is inserted into the mating slot. Thus, through the mating of the support rod 6 with the inner peripheral wall of the mating slot, the movement of the test frame 42 in the vertical, radial, and circumferential directions can be better restricted, thereby improving the reliability of the support rod 6 in supporting the test frame 42 and keeping the test frame 42 in the test position.

[0068] According to some embodiments of this utility model, such as Figure 2 and Figure 3 As shown, the measuring assembly 4 also includes a first drive mechanism 43, which drives the test frame 42 to move between a test position and an avoidance position. The first drive mechanism 43 and the support rod 6 are located on opposite sides of the test frame 42 in the horizontal direction. Thus, the support rod 6 and the first drive mechanism 43 can support the test frame 42 from opposite sides, thereby improving the stability of the test frame 42 in the test position.

[0069] In some embodiments, such as Figures 3-5 As shown, the output end of the first drive mechanism 43 is connected to the reinforcing plate 425, and the support rod 6 cooperates with the reinforcing plate 425 in the support position, so that the force exerted by the first drive mechanism 43 and the support rod 6 on the test frame 42 is concentrated on the reinforcing plate 425. The measuring component 4 also includes a connecting bracket 44, which is connected to the bottom of the test frame 42 and is slidably disposed in the receiving cavity 51 along the radial direction of the upper furnace cylinder 1. If the connecting bracket 44 can be a slide rail structure, the movement direction of the test frame 42 can be stably controlled by the sliding of the connecting bracket 44, so as to improve the stability of the test frame 42 in the movement between the test position and the avoidance position.

[0070] The crystal growth apparatus according to a second aspect embodiment of the present invention is described below with reference to the accompanying drawings.

[0071] According to a second aspect of the present invention, a crystal growth apparatus includes: a seed crystal length measuring device 100, a furnace body and a crucible. The furnace body is located on the lower side of the upper furnace cylinder 1, and a main furnace chamber suitable for communicating with the auxiliary furnace chamber 11 is formed inside the furnace body. The crucible is used to hold molten molten material and is located inside the main furnace chamber.

[0072] According to the crystal growth apparatus of the second aspect of this utility model, by setting the rangefinder 41 and the test frame 42 located at the test position in the auxiliary furnace chamber 11, the length of the portion of the seed crystal 200 extending downward from the seed crystal clamp 3 can be measured without opening the auxiliary furnace chamber 11 through the cooperation of the seed crystal shaft 2, the seed crystal clamp 3, the seed crystal 200, the rangefinder 41 and the test frame 42. This can improve the accuracy of the seed crystal 200 length measurement and reduce the risk of air leakage in the auxiliary furnace chamber 11 during the seed crystal 200 length measurement process. This can avoid the impact of air leakage in the auxiliary furnace chamber 11 on the growth thermal field of the seed crystal 200, and help improve the growth efficiency and quality of the crystal.

[0073] In some embodiments, such as Figure 2 and Figure 3 As shown, the seed crystal length measuring device 100 also includes an isolation valve 7, which is located at the downward opening of the auxiliary furnace chamber 11 to control the connection or disconnection between the auxiliary furnace chamber 11 and the main furnace chamber.

[0074] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0075] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0076] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A seed crystal length measuring device, characterized in that, include: The upper furnace drum has an auxiliary furnace chamber; A seed crystal shaft is provided in the upper furnace cylinder in a vertically movable manner. The lower end of the seed crystal shaft is located in the auxiliary furnace chamber and is provided with a seed crystal clamp, which is used to hold the seed crystal. The measuring component includes a rangefinder and a test frame. The rangefinder is installed in the upper furnace cylinder and located in the auxiliary furnace chamber. The rangefinder is located above or below the test frame. The test frame is movable between a test position and an avoidance position. In the test position, the test frame is located in the auxiliary furnace chamber and is located below and opposite to the seed crystal fixture. In the avoidance position, the test frame is located outside the auxiliary furnace chamber. The test frame includes a mounting bracket and a limiting plate and a movable plate disposed on the mounting bracket. The movable plate is located below the limiting plate. The rangefinder is used to measure the distance between the rangefinder and the upper surface of the movable plate in the vertical direction. The movable plate is movable relative to the mounting bracket in the vertical direction between a first position and a second position. The first position is located above the second position. The movable plate is adapted to be pushed downward from the first position to the second position by a seed crystal on the seed crystal clamp. In the first position, the seed crystal clamp is spaced apart from the limiting plate. In the second position, the seed crystal clamp abuts against the upper surface of the limiting plate.

2. The seed crystal length measuring device according to claim 1, characterized in that, The limiting plate has a first clearance hole extending vertically. At the test position, the projection of the seed crystal on the horizontal plane is the first projection, and the projection of the first clearance hole on the horizontal plane is the second projection. The first projection is located within the second projection. The limiting plate also has a second clearance hole extending vertically. The second clearance hole is spaced apart from the first clearance hole. At the test position, the projection of the rangefinder on the horizontal plane is the third projection, and the projection of the second clearance hole on the horizontal plane is the fourth projection. The third projection is located within the fourth projection.

3. The seed crystal length measuring device according to claim 1, characterized in that, At the test position, the limiting plate is grounded, the seed crystal fixture is energized, and the measuring component further includes a detection module for detecting the voltage of the seed crystal fixture.

4. The seed crystal length measuring device according to claim 1, characterized in that, The measuring assembly further includes a reset mechanism, which includes an electromagnetic plate disposed on the underside of the movable plate. At least a portion of the movable plate is a magnet and is located in the magnetic field generated by the electromagnetic plate. The electromagnetic plate exerts an upward magnetic force on the movable plate.

5. The seed crystal length measuring device according to claim 4, characterized in that, A pressure sensor is provided at the bottom of the movable plate. The pressure sensor is used to detect the downward pressure of the movable plate. The pressure value F' of the pressure sensor satisfies: F'=M1*G+M2*G+ΔF, 0.1M3*G<ΔF≤0.5M3*G; where M1 is the weight of the movable plate, M2 is the weight of the electromagnetic plate, M3 is the weight of the seed crystal 200, and G is the gravitational acceleration.

6. The seed crystal length measuring device according to claim 1, characterized in that, The outer periphery of the upper furnace cylinder is provided with a receiving chamber, and a receiving cavity is formed inside the receiving chamber. The peripheral wall of the upper furnace cylinder is provided with a connecting port, and the receiving cavity is connected to the auxiliary furnace chamber through the connecting port. In the avoidance position, the test frame is located inside the receiving cavity.

7. The seed crystal length measuring device according to claim 6, characterized in that, The connection port is equipped with a switch door, which is used to open or close the connection port.

8. The seed crystal length measuring device according to any one of claims 1-7, characterized in that, It also includes a support rod that is movable between a supported position and a retracted position. In the supported position, the support rod extends into the auxiliary furnace chamber and cooperates with the test frame to hold the test frame in the test position. In the retracted position, the support rod is located outside the auxiliary furnace chamber.

9. The seed crystal length measuring device according to claim 8, characterized in that, A mating slot is formed on the outer peripheral surface of the test frame, and the support rod located at the support position is detachably plugged into the test frame located at the test position.

10. The seed crystal length measuring device according to claim 8, characterized in that, The measuring assembly further includes a first drive mechanism for driving the test frame to move between the test position and the avoidance position. The first drive mechanism and the support rod are located on opposite sides of the test frame in the horizontal direction.

11. A crystal growth apparatus, characterized in that, include: Seed crystal length measuring device according to any one of claims 1-10; A furnace body is located on the lower side of the upper furnace cylinder, and a main furnace chamber is formed inside the furnace body to communicate with the auxiliary furnace chamber; A crucible, used to hold molten metal and located within the main furnace chamber.

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