Crystal bar processing production line and production process thereof

Abstract

The invention relates to a crystal bar processing production line and a production process thereof, and belongs to the technical field of crystal bar processing. The raw material purification line is used for purifying the prepared crystal bar production raw materials; the crystal bar generating line is used for smelting the high-purity polycrystalline silicon to finally generate a crystal bar; the head and tail removing line is used for cutting off the head and the tail of the generated crystal bar; the sampling detection line is used for sampling and detecting the end-removed crystal bar slices; the grinding line is used for grinding the outer diameter of the crystal bar; the coding line is used for coding the crystal bar; and the crystal bar cache line is used for storing the crystal bars subjected to code printing. The crystal bar processing production line and the production process thereof are a complex and fine production process, and have advanced equipment, automatic processing, strict management and quality control means to ensure the product quality and the production efficiency, so that the stability and controllability of the production process are ensured, the product quality is ensured to meet the use requirements, and the production cost is reduced. And the consistency of products is good, so that the processing yield is effectively improved.

Description

Technical Field

[0001] The invention relates to a crystal rod processing production line and a production process thereof, and belongs to the technical field of crystal rod processing. Background Art

[0002] Single crystal silicon rods are an important component of semiconductor materials and are widely used in electronics, optoelectronics, solar energy and other fields. When manufacturing crystal rods, the Czochralski method is usually used to prepare the crystal rods. The growth process of the crystal rods is melting (placing the block of high-purity polycrystalline silicon in a graphite crucible and heating it to above its melting point of 1420°C to completely melt it), neck growth (after the temperature of the silicon slurry stabilizes, slowly insert the crystal seed in the direction of <1.0.0> into it, and then slowly lift the crystal seed upward to reduce its diameter to a certain size, maintain this diameter and stretch it 100-200mm to eliminate the difference in grain arrangement orientation in the crystal seed), and crown growth (neck growth). After the growth is completed, the lifting speed and temperature are slowly reduced to gradually increase the neck diameter to the required size such as 5, 6, 8, 12 inches, etc.), crystal growth (continuously adjust the lifting speed and melting temperature to maintain a fixed crystal rod diameter until the crystal rod length reaches the predetermined value), tail growth (when the crystal rod length reaches the predetermined value, gradually increase the lifting speed and increase the melting temperature to gradually reduce the crystal rod diameter to avoid displacement and slip caused by thermal stress, and finally completely separate the crystal rod from the liquid surface), and finally obtain a complete crystal rod.

[0003] The most widely used single crystal silicon manufacturing process is to use the Czochralski method to manufacture single crystal silicon. Compared with other manufacturing processes, it has certain advantages in terms of manufacturing cost and performance of single crystal silicon. However, the existing processing production line and production process for manufacturing crystal rods by the Czochralski method have shortcomings, the quality of the manufactured crystal rods is unstable, and the consistency of the products is poor. Based on this, the present invention provides a crystal rod processing production line and a production process thereof. Summary of the invention

[0004] In view of this, the present invention provides a crystal rod processing production line and a production process thereof, which can ensure the stability and controllability of the production process, ensure that the quality of the product meets the use requirements, and the consistency of the product is good, so that the processing yield is effectively improved.

[0005] The present invention provides a crystal rod processing production line, and the proposed technical solution is:

[0006] Raw material purification line: used to purify the prepared raw materials for producing crystal rods, the raw material purification line includes an arc furnace for producing crude silicon and a distillation line for producing high-purity polysilicon;

[0007] Crystal rod growth line: used to melt high-purity polysilicon to finally generate crystal rods. The crystal rod growth line includes a graphite crucible used to heat the high-purity polysilicon to above the melting point to completely melt it. The temperature gradient must be strictly controlled and equipped with a precision temperature control system;

[0008] Head and tail removal line: used to cut off the head and tail of the generated crystal rod, the head and tail removal line includes a cutting machine station that can automatically align the tool and an automatic head and tail material removal station for removing the removed head and tail materials;

[0009] Sampling and testing line: used for sampling and testing the slices of the cut-off and tail-off crystal ingots. The sampling and testing line includes a slicer for slicing from the crystal ingots and a variety of testing equipment for testing relevant quality parameters;

[0010] Grinding line: used for grinding the outer diameter of the crystal rod, the grinding line includes a grinder, and is used to obtain a crystal rod of a target diameter;

[0011] Coding line: used for coding the crystal ingots; the coding line includes an automatic coding machine;

[0012] Crystal rod cache line: used to store the coded crystal rods, the crystal rod cache line includes a material transfer robot and a storage warehouse for transferring and transporting crystal rods.

[0013] Furthermore, the raw material for producing the crystal rod is mainly silicon dioxide, which reacts with a reducing agent through an electric arc furnace to generate crude silicon, and then the silicon is gasified into trichlorosilane through a chlorination reaction and a distillation line, and then reduced to generate high-purity polysilicon.

[0014] Furthermore, the crystal rod forming line uses a graphite crucible to heat the high-purity polysilicon raw material to above the melting point to completely melt it, then selects a seed crystal with a clear crystal orientation and no defects, slowly contacts the seed crystal with the melt, controls the temperature, pulling speed and rotation speed, and allows the silicon crystal to grow along the lattice structure of the seed crystal until the desired crystal rod length is reached.

[0015] Furthermore, the entire process of the crystal rod forming line is carried out in an inert gas protection environment, and the inert gas is argon to avoid oxidation or introduction of impurities.

[0016] Furthermore, the lattice structures of the head and tail of the crystal rod are unstable and have low quality.

[0017] Furthermore, the detection equipment includes a resistivity tester, a microwave photoconductivity attenuation meter, an infrared absorption spectrometer, a gas chromatograph and an X-ray diffractometer.

[0018] Furthermore, a conveying device is arranged between the production lines for conveying and transporting production materials and crystal rods.

[0019] The production process based on the above production line is characterized by comprising the following steps:

[0020] S1: Power on the production line, check that the equipment on the entire production line is operating normally, and check that there are no residual tooling obstacles on the production line;

[0021] S2: Adding raw silicon dioxide for ingot production into an electric arc furnace to react with a reducing agent to generate crude silicon, followed by chlorination and distillation to generate high-purity polysilicon;

[0022] S3: The crystal rod is prepared by the Czochralski method. The growth steps of the crystal rod are melting, neck growth, crown growth, crystal growth, and tail growth, and finally a complete crystal rod is obtained;

[0023] S4: cutting off the head and tail of the generated crystal rod and performing slice inspection;

[0024] S5: During the growth process, the outer diameter and roundness of the crystal rod may have certain deviations, which are ground by a grinder.

[0025] S6: The crystal ingots are coded and stored in the warehouse.

[0026] Beneficial effects of the present invention:

[0027] The crystal rod processing production line and its production process in the present invention is a complex and sophisticated production process, which has advanced equipment, automated processing, strict management and quality control measures to ensure product quality and production efficiency, to ensure the stability and controllability of the production process, to ensure that the quality of the product meets the use requirements, the product consistency is good, and the processing yield is effectively improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a crystal rod processing production line of the present invention. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present invention will be described in detail below.

[0030] The directional terms such as up, down, left, right, front, back, front, back, top, bottom, etc. mentioned or may be mentioned in this specification are defined relative to their structure and are relative concepts. Therefore, they may change accordingly according to their different locations and different usage states; therefore, these or other directional terms should not be interpreted as restrictive terms.

[0031] The singular forms "a", "said" and "the" used in this specification are intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0032] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and implementation methods. It should be understood that the implementation methods described herein are only used to explain this application and are not used to limit this application.

[0033] The present invention provides a crystal rod processing production line, comprising

[0034] Raw material purification line: used to purify the prepared raw materials for crystal rod production. The raw material purification line includes an arc furnace for producing crude silicon and a distillation line for producing high-purity polysilicon. The raw material for crystal rod production is mainly silicon dioxide, which is reacted with a reducing agent (such as carbon or coke) in an arc furnace to produce crude silicon, and then the silicon is gasified into trichlorosilane through a chlorination reaction and a distillation line, and then reduced to produce high-purity polysilicon;

[0035] Crystal rod growth line: used to melt high-purity polysilicon and finally generate crystal rods. The crystal rod growth line includes a graphite crucible used to heat the high-purity polysilicon to above the melting point to completely melt it. The temperature gradient needs to be strictly controlled and equipped with a precision temperature control system. The high-purity polysilicon raw material is heated to above the melting point by using a graphite crucible to completely melt it. Then, a seed crystal with a clear crystal orientation and no defects is selected, and the seed crystal is slowly brought into contact with the melt. The temperature, pulling speed and rotation speed are controlled to allow the silicon crystal to grow along the lattice structure of the seed crystal until the desired crystal rod length is reached. The entire process of the crystal rod growth line is carried out in an inert gas (such as argon) protective environment to avoid oxidation or the introduction of impurities.

[0036] Head and tail removal line: used to cut off the head and tail of the generated crystal rod. The lattice structure of the head and tail of the crystal rod is unstable and has low quality. The head and tail removal line includes a cutting machine station that can automatically align the tool and an automatic head and tail material removal station for removing the removed head and tail materials. The head and tail are automatically cut off by the cutting machine station, and the cut head and tail are removed by the automatic head and tail material removal station.

[0037] Sampling and testing line: used for sampling and testing the slices of the cut-off and tail-off crystal rods. The sampling and testing line includes a slicer for slicing from the crystal rods and a variety of testing equipment for testing relevant quality parameters. The testing equipment includes a resistivity tester, a microwave photoconductivity attenuation meter, an infrared absorption spectrometer, a gas chromatograph, and an X-ray diffractometer, etc., which are used for quality testing such as resistivity measurement, minority carrier lifetime measurement, oxygen content measurement, carbon content measurement, and dislocation density measurement;

[0038] Grinding line: used to grind the outer diameter of the crystal rod. The grinding line includes a grinder, which is used to obtain a crystal rod of target diameter. During the growth process of the crystal rod, its outer diameter size and roundness may have certain deviations, so it is necessary to perform outer diameter grinding. Through the grinder, the outer diameter size and shape error of the crystal rod can be made less than the allowable deviation to meet the requirements of subsequent processing;

[0039] Coding line: used for coding the crystal ingots; the coding line includes an automatic coding machine;

[0040] Crystal rod cache line: used to store the coded crystal rods, the crystal rod cache line includes a material transfer robot and a storage warehouse for transferring and transporting crystal rods.

[0041] As an optional embodiment, a conveying device is arranged between the production lines for conveying and transporting production materials and crystal rods.

[0042] The production process based on the above production line is characterized by comprising the following steps:

[0043] S1: Power on the production line, check that the equipment on the entire production line is operating normally, and check that there are no residual tooling obstacles on the production line;

[0044] S2: Adding raw silicon dioxide for ingot production into an electric arc furnace to react with a reducing agent to generate crude silicon, followed by chlorination and distillation to generate high-purity polysilicon;

[0045] S3: A crystal rod is prepared by the Czochralski method. The growth process of the crystal rod is melting (a block of high-purity polycrystalline silicon is placed in a graphite crucible and heated to a melting point of 1420°C or above to completely melt it), neck growth (after the temperature of the silicon slurry is stable, a seed crystal in the direction of <1.0.0> is slowly inserted into it, and then the seed crystal is slowly lifted up to reduce its diameter to a certain size, and this diameter is maintained and elongated by 100-200mm to eliminate the orientation difference of the grain arrangement in the seed crystal), crown growth (after the neck growth is completed, the lifting speed and temperature are slowly reduced to gradually increase the neck diameter to the required size such as 5, 6, 8, 12 inches, etc.), crystal growth (the lifting speed and melting temperature are continuously adjusted to maintain a fixed crystal rod diameter until the crystal rod length reaches a predetermined value), tail growth (when the crystal rod length reaches a predetermined value, the lifting speed is gradually increased and the melting temperature is increased to gradually reduce the crystal rod diameter to avoid displacement and slippage caused by thermal stress, and finally the crystal rod is completely separated from the liquid surface), and finally a complete crystal rod is obtained;

[0046] S4: cutting off the head and tail of the generated crystal rod and performing slice inspection;

[0047] S5: During the growth process, the outer diameter and roundness of the crystal rod may have certain deviations, which are ground by a grinder.

[0048] S6: The crystal ingots are coded and stored in the warehouse.

[0049] The crystal rod processing production line and its production process in the present invention is a complex and sophisticated production process, which has advanced equipment, automated processing, strict management and quality control measures to ensure product quality and production efficiency, to ensure the stability and controllability of the production process, to ensure that the quality of the product meets the use requirements, the product consistency is good, and the processing yield is effectively improved.

[0050] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A crystal ingot processing production line, characterized in that: include Raw material purification line: used to purify the prepared raw materials for producing crystal rods, the raw material purification line includes an arc furnace for producing crude silicon and a distillation line for producing high-purity polysilicon; Crystal rod growth line: used to melt high-purity polysilicon to finally generate crystal rods. The crystal rod growth line includes a graphite crucible used to heat the high-purity polysilicon to above the melting point to completely melt it. The temperature gradient must be strictly controlled and equipped with a precision temperature control system; Head and tail removal line: used to cut off the head and tail of the generated crystal rod, the head and tail removal line includes a cutting machine station that can automatically align the tool and an automatic head and tail material removal station for removing the removed head and tail materials; Sampling and testing line: used for sampling and testing the slices of the cut-off and tail-off crystal ingots. The sampling and testing line includes a slicer for slicing from the crystal ingots and a variety of testing equipment for testing relevant quality parameters; Grinding line: used for grinding the outer diameter of the crystal rod, the grinding line includes a grinder, and is used to obtain a crystal rod of a target diameter; Coding line: used for coding the crystal ingots; the coding line includes an automatic coding machine; Crystal rod cache line: used to store the coded crystal rods, the crystal rod cache line includes a material transfer robot and a storage warehouse for transferring and transporting crystal rods.

2. A crystal ingot processing production line according to claim 1, characterized in that: The raw material for the production of the crystal rod is mainly silicon dioxide, which reacts with a reducing agent in an electric arc furnace to produce crude silicon, and then the silicon is gasified into trichlorosilane through a chlorination reaction and a distillation line, and then reduced to produce high-purity polysilicon.

3. The crystal ingot processing production line according to claim 1, characterized in that: The crystal rod production line uses a graphite crucible to heat high-purity polysilicon raw materials to above the melting point to completely melt them, then selects a seed crystal with a clear crystal orientation and no defects, slowly contacts the seed crystal with the melt, controls the temperature, pulling speed and rotation speed, and allows the silicon crystal to grow along the lattice structure of the seed crystal until the desired crystal rod length is reached.

4. A crystal ingot processing production line according to claim 3, characterized in that: The entire process of the crystal rod forming line is carried out in an inert gas protection environment, and the inert gas is argon to avoid oxidation or introduction of impurities.

5. The crystal ingot processing production line according to claim 1, characterized in that: The lattice structures of the head and tail of the crystal rod are unstable and have low quality.

6. The crystal ingot processing production line according to claim 1, characterized in that: The detection equipment includes a resistivity tester, a microwave photoconductivity attenuation instrument, an infrared absorption spectrometer, a gas chromatograph and an X-ray diffractometer.

7. The crystal ingot processing production line according to claim 1, characterized in that: Conveying devices are arranged between the production lines for conveying and transporting production raw materials and crystal rods.

8. A production process of the production line according to any one of claims 1 to 7, characterized in that: The steps include: S1: Power on the production line, check that the equipment on the entire production line is operating normally, and check that there are no residual tooling obstacles on the production line; S2: Adding raw silicon dioxide for ingot production into an electric arc furnace to react with a reducing agent to generate crude silicon, followed by chlorination and distillation to generate high-purity polysilicon; S3: The crystal rod is prepared by the Czochralski method. The growth steps of the crystal rod are melting, neck growth, crown growth, crystal growth, and tail growth, and finally a complete crystal rod is obtained; S4: cutting off the head and tail of the generated crystal rod and performing slice inspection; S5: During the growth process, the outer diameter and roundness of the crystal rod may have certain deviations, which are then ground by a grinder. S6: The crystal ingots are coded and stored in the warehouse.

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