Novel single crystal furnace feeding method

Abstract

The invention belongs to the technical field of single crystal production, and relates to a novel single crystal furnace feeding method, which comprises the following steps: starting a second feeding program at a slow cooling stage after single crystal ending, controlling the single crystal to rise at a set speed, and adjusting a plurality of related parameters of the single crystal furnace, and feeding the single crystal through an external feeder while the single crystal rises. The feeding device has the beneficial effects that feeding is carried out while the single crystal is slowly cooled in the furnace, feeding is carried out in advance under the condition that the tail quality of the single crystal is ensured, and the efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of single crystal production and relates to a novel single crystal furnace charging method. Background Art

[0002] In the context of the photovoltaic industry's pursuit of low cost and high efficiency, reducing labor waste and improving labor utilization can effectively increase production capacity, thereby reducing costs and improving market competitiveness. In terms of single crystals, cost reduction measures mainly include new technologies, new processes such as high pulling speed, large loading, multiple crystal pulling, and the application of supporting new thermal field materials. Among them, multiple crystal pulling requires multiple re-investments (i.e., adding materials). During the re-investment process, the re-investment time accounts for 15% of the total operating time. In the prior art, the re-investment process is generally carried out after the single crystal is finished and the slow cooling is completed. The slow cooling and re-investment time of the single crystal have no output and are regarded as invalid working hours. In addition, the re-investment requires a large number of personnel and high labor intensity. Therefore, a new single crystal furnace charging method is needed to solve the above technical problems. Summary of the invention

[0003] In order to solve the above-mentioned technical problems, the present invention provides a new single crystal furnace charging method, which can add materials while slowly cooling down, reduce the reinvestment time and labor intensity, and effectively improve the production capacity, thereby realizing early charging while ensuring the quality of the tail of the single crystal, thereby improving efficiency.

[0004] The technical solution adopted by the present invention is: a new single crystal furnace charging method, characterized in that it includes the following steps:

[0005] In the slow cooling stage after the single crystal is finished, the second feeding program is started to control the single crystal to rise at a set speed, and multiple relevant parameters of the single crystal furnace are adjusted so that the single crystal can be fed through an external feeder while rising.

[0006] Furthermore, in the second feeding procedure, the crucible rotation speed is kept unchanged.

[0007] Furthermore, the set speed is 500-800 mm / min.

[0008] Furthermore, the multiple related parameters include heater power, furnace pressure, argon gas flow rate, crucible position and guide tube position.

[0009] Furthermore, the specific adjustments of the multiple related parameters by the second feeding procedure include increasing the heater power by 50-80 kW, reducing the furnace pressure to 1-10 Torr, increasing the argon flow rate to 200-300 slpm, lowering the crucible position to 0-50 mm, and increasing the guide tube position to 100-200 mm.

[0010] Furthermore, in the single crystal finishing stage, when the finishing length of the single crystal meets a preset value, a first feeding procedure is started.

[0011] Furthermore, the preset value is 95-105 mm.

[0012] Furthermore, specific adjustments to the first charging procedure include reducing heater power to 30-50 kW, increasing furnace pressure to 15-20 Torr, reducing crucible speed to 1-3 r / min, and increasing single crystal lifting speed to 300-500 mm / min.

[0013] Furthermore, the external feeder is connected to the pre-feeding port of the single crystal furnace.

[0014] Furthermore, the first feeding program and the second feeding program are electrically connected to a control system of the single crystal furnace.

[0015] The present invention relates to a novel single crystal furnace charging method, in which an external feeder is controlled to feed the single crystal while the temperature of the single crystal is slowly lowered in the furnace, so that the feeding is achieved in advance while ensuring the quality of the tail of the single crystal, and the efficiency is greatly improved:

[0016] 1. In the final stage, start the first feeding procedure to create an atmosphere suitable for the finalization of the single crystal and to quickly heat up in advance, so as to pave the way for the subsequent slow cooling and feeding. This can not only quickly take out the single crystal, but also prevent the single crystal from bursting due to thermal stress;

[0017] 2. During the slow cooling stage, start the second feeding program to feed the single crystal while it is being lifted, to prevent dust from drifting and silicon liquid from splashing in the furnace, saving work time and improving efficiency;

[0018] 3. The first charging procedure and the second charging procedure cooperate with each other to ensure the quality of the tail of the single crystal and to feed in advance. At the same time, all information is synchronized to the furnace, which improves the degree of automation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of the flow chart of the embodiment provided by the present invention. DETAILED DESCRIPTION

[0020] In order to make the objectives, technical solutions and advantages of the present disclosure more clearly understood, the present disclosure is further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0021] However, it should be understood that these descriptions are exemplary only and are not intended to limit the scope of the present disclosure. In the following detailed description, for ease of explanation, many specific details are set forth to provide a comprehensive understanding of the embodiments of the present disclosure. However, it is apparent that one or more embodiments may also be implemented without these specific details. In addition, in the following description, the description of the known technology is omitted to avoid unnecessary confusion of the concepts of the present disclosure.

[0022] The terms used herein are only for describing specific embodiments and are not intended to limit the present disclosure. The term "comprising" used herein indicates the existence of features, steps, operations, but does not exclude the existence or addition of one or more other features.

[0023] In the case of using expressions such as "at least one of A, B, and C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, and C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.). In the case of using expressions such as "at least one of A, B, or C, etc.", it should generally be interpreted in accordance with the meaning of the expression generally understood by those skilled in the art (for example, "a system having at least one of A, B, or C" should include but is not limited to a system having A alone, B alone, C alone, A and B, A and C, B and C, and / or A, B, C, etc.).

[0024] All terms (including technical and scientific terms) used herein have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein should be interpreted as having a meaning consistent with the context of this specification, and should not be interpreted in an idealized or overly rigid manner.

[0025] Figure 1 The following schematically shows an application flow chart of a novel single crystal furnace charging method according to an embodiment of the present disclosure. In this embodiment, an automatic charging program is placed in the control system of the furnace, which is respectively connected with the single crystal finishing and slow cooling related processes and all operation information is fed back to the control system. The automatic charging program includes a first charging program and a second charging program.

[0026] A new method for charging single crystal furnace, such as Figure 1 As shown, it is characterized in that it includes the following steps:

[0027] In the slow cooling stage after the single crystal is finished, the second feeding program is started to control the single crystal to rise at the set speed, and multiple related parameters of the single crystal furnace are adjusted so that the single crystal can be fed through the external feeder while it is rising. In the slow cooling stage after the single crystal is finished, the second feeding program is started synchronously so that the external feeder can be controlled to feed while the single crystal is rising, so that while ensuring the quality of the tail of the single crystal, feeding can be done during the process of taking the single crystal, realizing early feeding, saving working hours, improving efficiency, and saving a lot of construction period and cost.

[0028] Preferably, in the second charging procedure, the crucible rotation speed is kept unchanged.

[0029] Preferably, the set speed is 500-800 mm / min. In the second feeding procedure, the single crystal is controlled to rise at a set speed of 500-800 mm / min.

[0030] Preferably, the multiple related parameters include heater power, furnace pressure, argon flow rate, crucible position and guide tube position. In the second feeding procedure, multiple related parameters are adjusted synchronously, so that the feeding can be done in advance while ensuring the quality of the tail of the single crystal, thereby improving efficiency.

[0031] Preferably, the specific adjustment of the multiple related parameters in the second charging procedure includes increasing the heater power by 50-80kW, reducing the furnace pressure to 1-10Torr, increasing the argon flow rate to 200-300slpm, lowering the crucible position to 0-50mm, and increasing the guide tube position to 100-200mm. In actual use, the above multiple related parameters can be adjusted in sequence. The technical solution does not limit the adjustment order of the parameters, and the user can flexibly adjust according to the operating habits.

[0032] Preferably, in the single crystal finishing stage, when the finishing length of the single crystal meets the preset value, the first feeding program is started. In this embodiment, when the finishing length of the single crystal is less than the preset value, the finishing continues until the finishing length is greater than or equal to the preset value, and the first feeding program is started to create an atmosphere suitable for the single crystal finishing and rapid temperature rise in advance, paving the way for the subsequent slow cooling and feeding links, which can not only quickly take out the single crystal, but also prevent the single crystal from bursting due to thermal stress, while meeting the feeding conditions and greatly shortening the working hours.

[0033] Preferably, the preset value is 95 to 105 mm.

[0034] Preferably, the preset value is 100 mm.

[0035] Preferably, the specific adjustment of the first charging procedure includes reducing the heater power to 30-50kW, increasing the furnace pressure to 15-20Torr, reducing the crucible speed to 1-3r / min, and increasing the single crystal lifting speed to 300-500mm / min. As above, in the first charging procedure, the adjustment order of the parameters is not restricted, and the user can flexibly adjust according to the operating habits.

[0036] Preferably, the external feeder is connected to the pre-feeding port of the single crystal furnace.

[0037] Preferably, the first feeding program and the second feeding program are electrically connected to the control system of the single crystal furnace. When in use, the automatic feeding program is placed in the control system of the furnace, and the furnace can receive information in time and understand the situation in the single crystal furnace and the progress of feeding, thereby improving the degree of automation. It should be noted that the technical solution does not specifically limit the structure of the external feeder, as long as the feeding function can be realized.

[0038] The present invention relates to a method for growing single crystal silicon. In the method, an external feeder is controlled to feed the single crystal while the temperature is slowly lowered in a furnace, so that the feeding is performed in advance while ensuring the quality of the tail of the single crystal, thereby greatly improving the efficiency:

[0039] 1. In the final stage, start the first feeding procedure to create an atmosphere suitable for the finalization of the single crystal and to quickly heat up in advance, so as to pave the way for the subsequent slow cooling and feeding. This can not only quickly take out the single crystal, but also prevent the single crystal from bursting due to thermal stress;

[0040] 2. During the slow cooling stage, start the second feeding program to feed the single crystal while it is being lifted, to prevent dust from drifting and silicon liquid from splashing in the furnace, saving work time and improving efficiency;

[0041] 3. The first charging procedure and the second charging procedure cooperate with each other to ensure the quality of the tail of the single crystal and to feed in advance. At the same time, all information is synchronized to the furnace, which improves the degree of automation.

[0042] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and cannot be considered to limit the scope of implementation of the present invention. All equivalent changes and improvements made within the scope of the present invention should still fall within the scope of the patent coverage of the present invention.

Claims

1. A novel single crystal furnace charging method, characterized in that: The steps include: In the slow cooling stage after the single crystal is finished, the second feeding program is started to control the single crystal to rise at a set speed, and multiple relevant parameters of the single crystal furnace are adjusted so that the single crystal can be fed through an external feeder while rising.

2. The novel single crystal furnace charging method according to claim 1, characterized in that: In the second charging procedure, the crucible rotation speed is kept constant.

3. The novel single crystal furnace charging method according to claim 1 is characterized in that: The set speed is 500-800 mm / min.

4. The novel single crystal furnace charging method according to any one of claims 1 to 3, characterized in that: The plurality of related parameters include heater power, furnace pressure, argon gas flow rate, crucible position and draft tube position.

5. The novel single crystal furnace charging method according to claim 4 is characterized in that: The specific adjustments of the multiple related parameters by the second feeding program include increasing the heater power by 50-80kW, reducing the furnace pressure to 1-10Torr, increasing the argon flow rate to 200-300slpm, lowering the crucible position to 0-50mm, and increasing the guide tube position to 100-200mm.

6. The novel single crystal furnace charging method according to claim 1 or 5, characterized in that: In the single crystal finishing stage, when the finishing length of the single crystal meets a preset value, a first feeding procedure is started.

7. The novel single crystal furnace charging method according to claim 6 is characterized in that: The preset value is 95-105 mm.

8. The novel single crystal furnace charging method according to claim 6, characterized in that: The specific adjustments of the first charging procedure include reducing the heater power to 30-50 kW, increasing the furnace pressure to 15-20 Torr, reducing the crucible speed to 1-3 r / min, and increasing the single crystal lifting speed to 300-500 mm / min.

9. The novel single crystal furnace charging method according to claim 6, characterized in that: The external feeder is connected to the pre-feeding port of the single crystal furnace.

10. The novel single crystal furnace charging method according to claim 6, characterized in that: The first feeding program and the second feeding program are electrically connected to a control system of the single crystal furnace.

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