Multi-seed crystal Czochralski furnace

Abstract

The utility model discloses a multi-seed crystal Czochralski furnace which comprises a furnace body, a seed crystal shaft is arranged at the top of the furnace body, and the utility model relates to the technical field of Czochralski furnaces. According to the multi-seed crystal Czochralski furnace, a melting and crystallizing environment is manufactured, raw materials are placed in the crucible to be heated and melted, the temperature is controlled to be slightly higher than the crystallizing temperature of silicon single crystals, it is ensured that the melted silicon materials can be crystallized on the surface of melt, and the Czochralski method for growing the silicon single crystals has the advantages that automatic control is easy to achieve, production efficiency is high, large-diameter silicon single crystals are easy to prepare, and production cost is low. The crystal growth speed is high, the purity and the integrity of the crystal are high, the impurity concentration in the single crystal is easy to control, the low-resistivity single crystal can be prepared, and the like, so that the high-quality large single crystal can be prepared by rotating the crucible and the seed rod towards the same direction under the condition that both the crucible and the seed rod have high rotating speeds; and the rotating speed difference between the crucible and the seed crystal rod is controlled within a reasonable range, so that crystal pulling is more efficient and higher in quality.

Description

Technical Field

[0001] The utility model relates to the technical field of vertical pulling furnaces, in particular to a multi-seed crystal vertical pulling furnace. Background Art

[0002] With the development of the world's photovoltaic industry, the quality requirements for silicon single crystals are getting higher and higher, and the diameter is getting larger and larger. Silicon single crystals have become the material basis for general high-quality photovoltaic cells and play an irreplaceable role. As far as silicon crystal growth and preparation are concerned, there are natural silicon crystals and artificial silicon crystals. The number of natural silicon crystals is very small, and generally silicon single crystals are artificially made. In order to prepare silicon single crystals with good performance, in production practice, through continuous research, practice and exploration, the silicon single crystal growth technology has been continuously improved. The methods used to grow single crystals from the melt include zone melting method, pedestal method, sheet single crystal growth method, webbed single crystal growth method, etc.

[0003] Currently, the zone melting method is also used to draw silicon cores. However, with this method, the number of silicon cores that can be drawn in each furnace is limited, and during the drawing process, the pulses generated by the stepper motor and AC motor used will affect the drawing process of the silicon core; the tungsten wire rope used to draw the silicon core on the pulling head cannot reach the optimal state in terms of rotation performance, destructive torque, and forward and reverse repeated torsion life, affecting the production efficiency. Summary of the invention

[0004] In view of the deficiencies in the prior art, the utility model provides a multi-seed crystal vertical pulling furnace, which solves the problems mentioned in the above background technology.

[0005] To achieve the above objectives, the utility model is implemented through the following technical solutions: a multi-seed crystal vertical pulling furnace, including a furnace body, a seed crystal shaft is arranged on the top of the furnace body, and a guide rod is fixedly connected to one side of the top of the inner wall of the furnace body, the surface of the seed crystal shaft is fixedly connected to an upper mounting plate, the surface of the seed crystal shaft is fixedly connected to a lower mounting plate below the upper mounting plate, a seed crystal chuck is rotatably connected between the upper mounting plate and the lower mounting plate, a large gear is fixedly connected to the surface of the seed crystal shaft between the upper mounting plate and the lower mounting plate, and a small gear meshing with the large gear is fixedly connected to the surface of the seed crystal chuck.

[0006] Preferably, the number of the seed crystal chucks is six, and the seed crystal chucks are arranged equidistantly in a ring shape.

[0007] Preferably, a first limiting plate is fixedly connected to one side of the top of the upper mounting plate, and a second limiting plate is fixedly connected to one side of the bottom of the lower mounting plate.

[0008] Preferably, one side of the first limiting plate and the second limiting plate is fixedly connected with a self-lubricating graphite copper sleeve, and the number of the self-lubricating graphite copper sleeves is two.

[0009] Preferably, the inner wall of the self-lubricating graphite copper sleeve is slidably connected to the surface of the guide rod.

[0010] Preferably, a flange is connected to the top end of the guide rod, and a threaded hole is formed on the surface of the flange.

[0011] Beneficial Effects

[0012] The utility model provides a multi-seed crystal vertical pulling furnace. Compared with the prior art, it has the following beneficial effects:

[0013] The multi-seed crystal vertical pulling furnace is provided with a seed crystal shaft through the top of the furnace body, and a guide rod is fixedly connected to one side of the top of the inner wall of the furnace body, the surface of the seed crystal shaft is fixedly connected to an upper mounting plate, the surface of the seed crystal shaft and located below the upper mounting plate is fixedly connected to a lower mounting plate, a seed crystal chuck is rotatably connected between the upper mounting plate and the lower mounting plate, a large gear is fixedly connected to the surface of the seed crystal shaft and located between the upper mounting plate and the lower mounting plate, and a small gear meshing with the large gear is fixedly connected to the surface of the seed crystal chuck. The process is completed by melting and recrystallizing ordinary silicon materials, and a melting and crystallization environment is created according to the crystallization law of silicon single crystals, and the raw materials are placed in a crucible The crucible is heated and melted, and the temperature is controlled to be slightly higher than the crystallization temperature of the silicon single crystal to ensure that the molten silicon material can crystallize on the surface of the melt. The Czochralski method for growing silicon single crystals has the advantages of easy automatic control, high production efficiency, easy preparation of large-diameter silicon single crystals, fast crystal growth rate, high crystal purity and integrity, easy control of impurity concentration in the single crystal, and the ability to prepare low-resistivity single crystals. It is a method for preparing high-quality large single crystals. Since the crucible and the seed crystal rod rotate in the same direction, the speed difference between the crucible and the seed crystal rod can be controlled within a reasonable range when both the crucible and the seed crystal rod have high rotation speeds, ensuring that the crystal pulling is completed more efficiently and with higher quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a cross-sectional view of the structure of the utility model;

[0015] Figure 2 It is a top view of the structure of the utility model;

[0016] Figure 3 For this utility model Figure 1 A partial enlarged view of the middle A;

[0017] Figure 4 For this utility model Figure 1 A partial enlarged view of point B in the middle.

[0018] In the figure: 1-furnace body, 2-seed crystal shaft, 3-guide rod, 4-upper mounting plate, 5-lower mounting plate, 6-seed crystal chuck, 7-large gear, 8-small gear, 9-first limit plate, 10-second limit plate, 11-self-lubricating graphite copper sleeve, 12-flange. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0020] See also Figure 1-4 The utility model provides a technical solution: a multi-seed crystal vertical pulling furnace, comprising a furnace body 1, a seed crystal shaft 2 is arranged on the top of the furnace body 1, and a guide rod 3 is fixedly connected to one side of the top of the inner wall of the furnace body 1, a flange 12 is connected to the top of the guide rod 3, and a threaded hole 13 is opened on the surface of the flange 12, an upper mounting plate 4 is fixedly connected to the surface of the seed crystal shaft 2, a first limit plate 9 is fixedly connected to one side of the top of the upper mounting plate 4, a self-lubricating graphite copper sleeve 11 is fixedly connected to one side of the first limit plate 9 and the second limit plate 10, and the number of the self-lubricating graphite copper sleeves 11 is set to two, the inner wall of the self-lubricating graphite copper sleeve 11 is slidably connected to the surface of the guide rod 3, and a second limit plate 10 is fixedly connected to one side of the bottom of the lower mounting plate 5.

[0021] A lower mounting plate 5 is fixedly connected to the surface of the seed crystal shaft 2 and is located below the upper mounting plate 4. A seed crystal chuck 6 is rotatably connected between the upper mounting plate 4 and the lower mounting plate 5. There are six seed crystal chucks 6, and the seed crystal chucks 6 are arranged equidistantly in a ring. A large gear 7 is fixedly connected to the surface of the seed crystal shaft 2 and is located between the upper mounting plate 4 and the lower mounting plate 5. A small gear 8 meshing with the large gear 7 is fixedly connected to the surface of the seed crystal chuck 6. At the same time, the contents not described in detail in this specification belong to the prior art known to those skilled in the art.

[0022] When in use, when the seed crystal shaft 2 rotates, it will drive the large gear 7 to rotate, and the small gear 8 will rotate under the drive of the large gear 7, so that the seed crystal chuck 6 rotates. The first limit plate 9 and the second limit plate 10 prevent the upper mounting plate 4 and the lower mounting plate 5 from rotating when the seed crystal shaft 2 rotates.

[0023] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0024] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-seed crystal vertical pulling furnace, comprising a furnace body (1), characterized in that: A seed crystal shaft (2) is arranged on the top of the furnace body (1), and a guide rod (3) is fixedly connected to one side of the top of the inner wall of the furnace body (1); an upper mounting plate (4) is fixedly connected to the surface of the seed crystal shaft (2); a lower mounting plate (5) is fixedly connected to the surface of the seed crystal shaft (2) and located below the upper mounting plate (4); a seed crystal chuck (6) is rotatably connected between the upper mounting plate (4) and the lower mounting plate (5); a large gear (7) is fixedly connected to the surface of the seed crystal shaft (2) and located between the upper mounting plate (4) and the lower mounting plate (5); and a small gear (8) meshing with the large gear (7) is fixedly connected to the surface of the seed crystal chuck (6).

2. A multi-seed crystal vertical pulling furnace according to claim 1, characterized in that: The number of the seed crystal chucks (6) is six, and the seed crystal chucks (6) are arranged in a ring-shaped manner with equal distances.

3. The multi-seed crystal vertical pulling furnace according to claim 1, characterized in that: A first limiting plate (9) is fixedly connected to one side of the top of the upper mounting plate (4), and a second limiting plate (10) is fixedly connected to one side of the bottom of the lower mounting plate (5).

4. A multi-seed crystal vertical pulling furnace according to claim 3, characterized in that: A self-lubricating graphite copper sleeve (11) is fixedly connected to one side of the first limiting plate (9) and the second limiting plate (10), and the number of the self-lubricating graphite copper sleeves (11) is two.

5. The multi-seed crystal vertical pulling furnace according to claim 4, characterized in that: The inner wall of the self-lubricating graphite copper sleeve (11) is slidably connected to the surface of the guide rod (3).

6. The multi-seed crystal vertical pulling furnace according to claim 1, characterized in that: The top end of the guide rod (3) is connected to a flange (12), and a threaded hole is provided on the surface of the flange (12).

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