Real-time monitoring device for residual amount of silicon liquid in single crystal furnace

Abstract

The utility model discloses a real-time monitoring device for residual silicon liquid in a single crystal furnace, which solves the problem that the residual silicon liquid cannot be directly and accurately measured by a traditional single crystal furnace. According to the device, the weight sensor is mounted on the supporting platform, and the PLC is used for transmitting acquired data to the monitoring platform in real time, so that dynamic monitoring on the total weight of the graphite support, the crucible and a silicon material in the graphite support, the crucible and the silicon material is realized. In the crystal pulling process, the system can automatically draw a chart about the change of the residual amount of the silicon liquid along with time, and when the silicon liquid is reduced to the preset early warning weight, the system automatically gives an alarm to prompt an operator to take corresponding measures. The device not only improves the accuracy of measuring the residual amount of the silicon liquid, but also optimizes the production process flow, reduces the production cost, and enhances the safety and stability of production.

Description

Technical Field

[0001] This utility model belongs to the field of photovoltaic crystal pulling technology, and specifically relates to a real-time monitoring device for the remaining amount of silicon liquid in a single crystal furnace. Background Technology

[0002] With the rapid development of the monocrystalline silicon industry, the monocrystalline silicon ingot pulling process needs further improvement and refinement. Precise management and operation have become crucial for the industry, while lower production costs are an effective way to enhance competitiveness. A real-time silicon liquid balance monitoring device can accurately measure the remaining silicon liquid in the crucible. When the balance falls below a certain set value, it notifies the process personnel to perform relevant process operations. This eliminates waste, achieves precise operation, and saves production costs. During the crystal pulling stage of the monocrystalline furnace process, the graphite heater provides a high-temperature environment, placing the crucible in the graphite holder under high temperature conditions. The silicon material placed within melts to form high-temperature silicon liquid, and the support platform provides support. As the pulling process progresses, the remaining high-temperature silicon liquid gradually decreases. Traditional monocrystalline furnaces estimate the amount of silicon liquid in the crucible by judging the silicon rod diameter using optical diameter measurement and visually observing the silicon liquid level. This method cannot directly and accurately determine the remaining silicon liquid and fails to achieve precise operation. Summary of the Invention

[0003] The technical problem this invention aims to solve is to provide a real-time monitoring device for the remaining silicon liquid level in a single crystal furnace. By adding a weight sensor and connecting its signal to a PLC for real-time data upload, accurate measurement of the remaining silicon liquid level can be achieved. This is more accurate than traditional methods such as optical diameter detection and visual estimation of the silicon liquid level, and can more effectively guide various operations during the crystal pulling process.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0005] A real-time monitoring device for the remaining silicon liquid in a single crystal furnace includes a monitoring device for the remaining silicon liquid installed between a graphite support and a rotating support platform. The monitoring device includes a buffer device and a weight sensor, and the weight sensor is electrically connected to a PLC controller.

[0006] Preferably, the buffer device and weight sensor are located inside the sleeve, which cooperates with the pressure rod and is connected to the rotating support platform. The pressure rod is connected to the graphite support. The buffer device can be a spring or high-temperature resistant rubber.

[0007] Preferably, the cross-section of the compression bar has a polygonal structure.

[0008] The present invention can achieve the following beneficial effects:

[0009] 1. By adding a weight sensor and connecting its signal to a PLC for real-time data upload, precise measurement of the remaining silicon liquid level can be achieved. This is more accurate than traditional methods such as optical diameter detection and visual estimation of the silicon liquid level, and can more effectively guide various operations during the crystal pulling process.

[0010] 2. Based on real-time monitoring data, operators can adjust the crystal pulling speed and other process parameters in a timely manner to ensure the stability of the production process and the consistency of product quality. This helps reduce the product defect rate caused by improper operation and improves overall production efficiency. Attached Figure Description

[0011] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0012] Figure 1 This is a diagram of the installation structure of this utility model;

[0013] Figure 2 This diagram shows the connection between the existing crucible, graphite holder, and rotating support platform.

[0014] Figure 3 This is a structural diagram of the real-time monitoring device for residual capacity of this utility model;

[0015] Figure 4 This is a schematic diagram illustrating the measurement principle of this utility model.

[0016] In the figure: 1. Optical diameter monitoring port; 2. Crucible; 3. Graphite support; 4. Graphite heater; 5. Insulation cover; 6. Rotary support platform; 7. Balance real-time monitoring device; 8. Buffer device; 9. Weight sensor; 10. Seed crystal rotation axis; 11. Seed crystal axis; 12. Seed crystal holder; 13. Protective gas; 14. Vacuum pump. Detailed Implementation

[0017] Preferred solutions include Figures 1 to 4 As shown, the real-time monitoring device for the remaining silicon liquid in a single crystal furnace includes:

[0018] When the single crystal furnace process reaches the crystal pulling stage, the graphite heater provides a high-temperature environment, which puts the crucible in the graphite holder under high temperature conditions. The silicon material placed in it melts and forms high-temperature silicon liquid. The support platform provides support. As the pulling process continues, the amount of high-temperature silicon liquid gradually decreases. Traditional single crystal furnaces use optical diameter measurement to determine the diameter of the silicon rod and visually measure the silicon liquid level to estimate the amount of silicon liquid in the crucible. This method cannot directly and accurately determine the amount of silicon liquid remaining, and it cannot achieve the purpose of precise operation.

[0019] This device transforms a traditional single-crystal furnace support platform by adding a weight sensor. The signal is then transmitted in real-time via a PLC to a monitoring platform, creating a silicon melt balance monitoring system. Operating principle: The graphite tray and crucible are placed on the silicon melt balance monitoring device. This device not only provides support but also records and reports the weight of the crucible + graphite tray + silicon material. During the crystal pulling stage, the real-time monitoring device provides feedback on the remaining silicon melt, accurately guiding subsequent operations. This achieves precise operation and saves production costs.

[0020] After the silicon liquid balance monitoring device is installed, once the crucible is placed on the rotating support platform, the "initial weight" is recorded in real time via a buffer device and a weight sensor. The signal is then transmitted and processed by a PLC and displayed on a graph. The program then begins to plot the silicon liquid balance over time. As the crystal pulling process progresses, the silicon liquid in the crucible gradually decreases, and the silicon liquid balance graph changes over time. When the silicon liquid balance decreases to the "warning weight," an alarm is triggered, notifying personnel to perform appropriate process operations in a timely manner. This achieves the goal of precise operation, avoids waste of production materials, and saves production costs.

[0021] The above embodiments are merely preferred technical solutions of this utility model and should not be considered as limitations on this utility model. The protection scope of this utility model should be the technical solution described in the claims, including equivalent substitutions of the technical features described in the claims. That is, equivalent substitutions and improvements within this scope are also within the protection scope of this utility model.

Claims

1. A real-time monitoring device for the remaining silicon liquid in a single crystal furnace, characterized in that: The device includes a silicon liquid balance monitoring device installed between the graphite holder and the rotating support platform. The silicon liquid balance monitoring device includes a buffer device and a weight sensor, which is electrically connected to the PLC controller.

2. The real-time monitoring device for the remaining silicon liquid in a single crystal furnace according to claim 1, characterized in that: The buffer device and weight sensor are located inside the sleeve. The sleeve is connected to the pressure rod and the rotating support platform. The pressure rod is connected to the graphite support.

3. The real-time monitoring device for the remaining silicon liquid in a single crystal furnace according to claim 1, characterized in that: The cross-section of the compression member is a polygonal structure.

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