Broken line detection and roller surface state monitoring system based on SiC crystal bar cutting process

Abstract

The invention relates to the technical field of SiC crystal bar cutting, in particular to a broken line detection and roller surface state monitoring system and method based on a CCD contour recognition technology, a laser displacement sensor and a water gun cleaning system. The system comprises a cutting module, a detection module and a cleaning module, and the real-time monitoring and analysis of the broken line position, the line arch variation and the roller surface state in the cutting process are realized by integrating various detection and cleaning devices. The stability of the cutting technology and the product quality can be remarkably improved, cutting failures caused by broken lines are reduced, roller surface damage is repaired in time, the service life of equipment is prolonged, mortar and impurities in the cutting process are effectively removed, and the cutting quality and the equipment cleanliness are improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of semiconductor material processing, and specifically relates to a technical solution for wire break detection and equipment status monitoring during the cutting process of SiC wafers. Background Art

[0002] Due to its excellent physical and chemical properties, such as high hardness, high thermal conductivity, and good chemical stability, silicon carbide (SiC) materials have been widely used in many industrial fields. Especially in the fields of precision machining, optical devices, and semiconductor manufacturing, the demand for SiC materials is increasing. However, existing SiC processing technologies still have many deficiencies in terms of precision, efficiency, and surface quality control. Traditional processing methods, such as mechanical grinding and chemical etching, often struggle to meet the requirements of modern industries for high precision, high efficiency, and low surface roughness. In addition, existing technologies are easily interfered by external environmental factors during the processing, resulting in unstable processing quality and difficulty in achieving automated and intelligent control.

[0003] Currently, SiC processing equipment based on CCD (Charge-Coupled Device) detection technology and multi-axis linkage processing systems has gradually become a research hotspot. Such equipment conducts real-time monitoring through high-resolution CCD sensors and combines multi-axis control systems to achieve high-precision processing of complex shapes. However, existing technologies still face some key problems in practical applications. For example, the control of stress distribution and thermal deformation of SiC materials during processing is not precise enough, easily leading to cracks or micro-defects on the material surface; at the same time, the optimization and adjustment of processing parameters lack systematicness and are difficult to adapt to the needs of SiC workpieces of different specifications and shapes. In addition, existing processing equipment still needs to be improved in terms of integration and intelligence, especially in real-time data acquisition, analysis, and feedback control, where there are obvious shortcomings.

[0004] On the other hand, existing SiC processing technologies have high requirements for the operating environment. For example, conditions such as temperature, humidity, and cleanliness need to be strictly controlled, which not only increases the operating cost of the equipment but also limits its application in a wider range of scenarios. At the same time, the selection and dosage control of auxiliary materials such as coolants and lubricants used during processing are not yet perfect, which may cause environmental pollution or resource waste. In addition, when achieving high-precision surface treatment with existing technologies, it often requires a long processing cycle and is difficult to meet the demand for high-efficiency production.

[0005] In summary, the current SiC material processing technology still has significant deficiencies in aspects such as precision control, surface quality improvement, environmental adaptability, and processing efficiency. To address the above problems, it is urgent to develop a SiC processing technology and equipment that can achieve high precision, high efficiency, and intelligent control. This technology should have real-time monitoring and feedback functions, be able to automatically adjust process parameters according to the dynamic changes during the processing, thereby improving the processing quality and efficiency, and at the same time reducing the impact on the environment. This innovation will provide important technical support for the further application of SiC materials in the high-end manufacturing field. Summary of the Invention

[0006] Aiming at the problems of low cutting efficiency and product quality decline caused by wire breakage and roller surface damage in the existing SiC ingot cutting process, the present invention proposes a wire breakage detection and roller surface state monitoring system and method based on CCD contour recognition technology, laser displacement sensors, and a water gun cleaning system. By integrating various detection and cleaning devices, the system realizes real-time monitoring and analysis of the wire breakage position, wire bow change amount, and roller surface state during the cutting process, thereby significantly improving the stability of the cutting process and product quality.

[0007] To achieve the above object, the present invention provides the following technical solutions: A wire breakage detection and roller surface state monitoring system based on the SiC ingot cutting process, comprising a cutting module, a detection module, and a cleaning module; the cutting module includes a cutting material plate, resin strips, and a cutting wire mesh. The cutting material plate is used to fix the SiC ingot, and the resin strips are arranged at both ends of the cutting material plate to enhance the fixing effect. The cutting wire mesh connects two rollers and maintains a stable state through a preset tension; the detection module includes a CCD contour recognition system and a laser displacement sensor. The CCD contour recognition system consists of a guide rail screw, a CCD contour recognition camera, and a laser calibration probe. The laser displacement sensor is installed above the cutting wire mesh; the cleaning module includes a water gun system, and the water gun system consists of a water supply pipe, a water return pipe, and a diversion cover.

[0008] Preferably, the cutting material plate is made of a rigid material, its surface flatness is Ra≤0.5μm, and its size is designed to be 150mm±0.2mm in length and 65mm±5mm in width.

[0009] Preferably, the width of the resin strip is 15mm and the thickness is 3mm.

[0010] Preferably, the tension range of the cutting wire mesh is set to 15N to 30N, and the cutting speed range is 0.5m / s to 2m / s.

[0011] Preferably, the resolution of the CCD contour recognition camera is 5MP, the magnification is 5× to 10×, and the working distance is 50mm to 500mm.

[0012] Preferably, the laser calibration probe is arranged beside the CCD contour recognition camera to assist in calibration to improve the detection accuracy.

[0013] Preferably, the measurement range of the laser displacement sensor is ±5μm, the detection angle is set at 25°, the working wavelength is 650nm ± 10nm, and the measurement accuracy is 0.01mm.

[0014] Preferably, the water supply pressure of the water gun system is set at 0.3MPa to 0.5MPa, the water flow rate is 5ml / s to 15ml / s, and the flow guide cover guides the water flow to optimize the cleaning effect.

[0015] Preferably, it further includes a PLC controller, which receives data from the CCD contour recognition system and the laser displacement sensor, and judges whether to trigger an alarm or start the cleaning module according to a preset algorithm.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: by integrating the CCD contour recognition technology, the laser displacement sensor and the water gun cleaning system, the automation level and product quality of the SiC crystal bar cutting process are significantly improved. Specifically, the present invention realizes the real-time monitoring of the wire break position and the wire bow change amount during the cutting process, reducing the cutting failure caused by wire breakage; at the same time, through the comprehensive monitoring of the surface state of the roller, damages such as bad grooves, broken grooves, and collapsed grooves are found and repaired in time, extending the service life of the equipment; in addition, the introduction of the water gun cleaning system effectively removes the mortar and impurities generated during the cutting process, improving the cutting quality and equipment cleanliness. In summary, the present invention provides an efficient and reliable SiC crystal bar cutting monitoring system and method, providing important support for the technological progress in related fields. Description of the Drawings

[0017] Figure 1 is a schematic diagram of the cutting process of the present invention; Figure 2 is a schematic diagram of the surface damage of the roller of the present invention; Figure 3 is a schematic diagram of the SiC crystal bar cutting of the present invention; Figure 4 is a schematic diagram of the water gun system of the present invention; Figure 5 is a schematic diagram of the CCD contour recognition system of the present invention; Figure 6 is a schematic diagram of the laser displacement sensor of the present invention; Figure 7 is a schematic diagram of the wire break position and the wire bow change amount of the present invention.

[0018] The reference numerals are as follows: 1. Crystal bar cutting direction; 2. Wire break position; 3. Roller; 4. Cutting material plate; 5. Cutting wire mesh; 6. Wire break; 7. Clean roller surface; 8. Bad groove; 9. Collapsed groove; 10. Sagging groove; 11. Deformation of the groove bottom; 12. Resin strip; 13. SiC crystal bar; 14. SiC crystal bar cutting seam; 15. Mortar in the cutting seam; 16. Water gun; 17. Water supply pipe; 18. Water return pipe; 19. Flow deflector; 20. Guide rail screw; 21. CCD contour recognition camera; 22. Laser calibration probe; 23. Roller surface; 26. Bad groove recognition angle; 27. Laser displacement sensor; 28. Sensor angle; 30. Wire bow change amount. Detailed implementation mode

[0019] The following will combine the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

[0020] The present invention provides a wire break detection and roller surface state monitoring system and method based on the SiC crystal bar cutting process, and will detail the technical solutions of the present invention in combination with the specific embodiments shown in the attached Figure 1 to the attached Figure 7 The specific embodiments are used to describe the technical solutions of the present invention in detail. In this embodiment, the system mainly consists of a cutting module, a detection module and a cleaning module, and realizes automatic control through a PLC controller. The specific structures and operation processes of each module are as follows.

[0021] The cutting module is the core part of the whole system, which is used to fix the SiC crystal bar and complete the cutting operation. As shown in the attached Figure 1 figure, the cutting material plate 4 is made of rigid material, and its surface is precision processed to ensure that the flatness reaches Ra≤0.5μm. Resin strips 12 are arranged at both ends of the cutting material plate 4 to enhance the fixing effect of the SiC crystal bar 13 and prevent the crystal bar from shifting during the cutting process. The cutting wire mesh 5 is connected to two rollers 3 and maintains a stable state through a preset tension. The tension range of the cutting wire mesh 5 is set to 15N to 30N to ensure that the wire mesh is evenly stressed during the cutting process. The size of the cutting material plate 4 is designed to be 150mm±0.2mm in length and 65mm±5mm in width, which can meet the cutting requirements of SiC crystal bars of different specifications. During the cutting process, the cutting wire mesh 5 moves along the crystal bar cutting direction 1, and the cutting speed is set to 0.5m / s to 2m / s to ensure the cutting efficiency and quality.

[0022] The detection module includes a CCD contour recognition system and a laser displacement sensor, which are used to monitor the wire break position, wire bow change amount and roller surface state in real time. As shown in the attached Figure 5As shown in the figure, the CCD contour recognition system consists of a guide rail screw 20, a CCD contour recognition camera 21, and a laser calibration probe 22. The guide rail screw 20 is arranged along the axial direction of the roller 3, used to support and drive the CCD contour recognition camera 21 to move along the surface 23 of the roller, ensuring that the entire surface of the roller is covered. The resolution of the CCD contour recognition camera 21 is 5MP, the magnification is from 5× to 10×, and the working distance is from 50mm to 500mm, which can accurately capture the subtle damage features on the surface of the roller. The laser calibration probe 22 is set beside the CCD contour recognition camera 21, used for auxiliary calibration to improve the detection accuracy. As attached Figure 6 As shown in the figure, the laser displacement sensor 27 is installed above the cutting wire mesh 5, with a measurement range of ±5μm and the detection angle set at 25°, to ensure the maximum detection range. The working wavelength of the laser displacement sensor 27 is 650nm ± 10nm, and the measurement accuracy is 0.01mm, which can realize the real-time monitoring of the broken wire position 2 and the wire bow change amount 30 during the high-speed cutting process.

[0023] The cleaning module includes a water gun system, used to remove the mortar and impurities on the surface of the roller and the cutting wire mesh. As attached Figure 4 As shown in the figure, the water gun system consists of a water supply pipe 17, a water return pipe 18, and a flow guide cover 19. The water supply pipe 17 is connected to the water source, the water return pipe 18 recycles the used water, and the flow guide cover 19 guides the water flow to optimize the cleaning effect. The water supply pressure of the water gun system is set at 0.3MPa to 0.5MPa, and the water flow rate is 5ml / s to 15ml / s, ensuring the cleaning effect while avoiding damage to the cutting wire mesh. The angle of the water jet from the water gun 16 is adjusted according to actual needs, usually set at 30° to 45°, to achieve the best cleaning effect.

[0024] The present invention realizes broken wire detection and roller surface state monitoring through the following steps: S1. Start the cutting module, fix the SiC ingot on the cutting plate, and cut it through the cutting wire mesh; S2. Start the CCD contour recognition system, move the CCD contour recognition camera along the guide rail screw, take an image of the roller surface and transmit it to the processing unit; S3. In the processing unit, use the image processing algorithm to analyze whether there are damage conditions such as bad grooves, chipped grooves, or collapsed grooves on the roller surface, and record the damage position and degree; S4. Start the laser displacement sensor, real-time monitor the state of the cutting wire mesh, detect the broken wire position and the wire bow change amount, and transmit the data to the processing unit; S5. If a broken wire or the wire bow change amount exceeds the preset threshold is detected, trigger the alarm device and pause the cutting operation; S6. Start the water gun system, clean the surface of the roller and the cutting wire mesh by spraying water, and remove the mortar and impurities; S7. After cleaning, restart the cutting module and continue the cutting operation. Embodiment

[0025] After starting the cutting module, the SiC ingot 13 is fixed on the cutting plate 4, and cutting operations are performed on it through the cutting wire mesh 5. During the cutting process, the cutting wire mesh 5 moves along the ingot cutting direction 1, and the cutting speed is set to 0.5 m / s to 2 m / s. At the same time, the CCD contour recognition system is started, and the CCD contour recognition camera 21 is moved along the guide rail screw 20 to capture images of the roller surface 23 and transmit them to the processing unit. In the processing unit, image processing algorithms are used to analyze whether there are damages such as bad grooves 8, chipped grooves 9, or collapsed grooves 10 on the roller surface, and record the damage positions and degrees. Meanwhile, the laser displacement sensor 27 is started to monitor the state of the cutting wire mesh 5 in real time, detect the wire break position 2 and the wire bow change amount 30, and transmit the data to the processing unit. If a wire break 6 or a wire bow change amount exceeding the preset threshold is detected, the alarm device is triggered and the cutting operation is paused.

[0026] As shown in the Figure 7 attachment, the detection results of the wire break position 2 and the wire bow change amount 30 are obtained in real time through the laser displacement sensor 27, and the sensor angle 28 is set to 25° to ensure the maximum detection range. When the wire bow change amount exceeds the preset value, the system will automatically adjust the tension of the cutting wire mesh 5 to restore the cutting stability. If a wire break 6 occurs, the cutting operation is immediately stopped, and the water gun system is started for cleaning. The water gun 16 sprays water to remove the mortar and impurities on the roller surface and the cutting wire mesh 5. After the cleaning is completed, the cutting module is restarted to continue the cutting operation.

[0027] The PLC controller receives data from the CCD contour recognition system and the laser displacement sensor, and judges whether to trigger an alarm or start the cleaning module according to the preset algorithm. The PLC controller also has a parameter adjustment function, and can adjust the cutting speed, the detection frequency of the laser displacement sensor, and the cleaning time of the water gun system according to the requirements of different cutting tasks. For example, when cutting a larger-diameter SiC ingot, the cutting speed can be appropriately reduced and the cleaning frequency can be increased to ensure the cutting quality and the equipment cleanliness.

[0028] In this embodiment, the designed dimensions of the cutting stock plate 4 are 150 mm ± 0.2 mm in length and 65 mm ± 5 mm in width. The width of the resin strip 12 is 15 mm and the thickness is 3 mm. The tension range of the cutting wire mesh 5 is set to 15 N to 30 N, and the cutting speed is 0.5 m / s to 2 m / s. The resolution of the CCD contour recognition camera 21 is 5 MP, the magnification is 5× to 10×, and the working distance is 50 mm to 500 mm. The measurement range of the laser displacement sensor 27 is ±5 μm, the detection angle is set to 25°, the working wavelength is 650 nm ± 10 nm, and the measurement accuracy is 0.01 mm. The water supply pressure of the water gun system is set to 0.3 MPa to 0.5 MPa, and the water flow rate is 5 ml / s to 15 ml / s. The setting of these parameters has been verified through multiple experiments and can meet the cutting requirements of SiC ingots with different specifications.

[0029] In practical applications, this system significantly improves the automation level and product quality of the SiC ingot cutting process. By real-time monitoring of the wire break position 2 and the wire bow change amount 30 during the cutting process, the cutting failures caused by wire breaks are reduced. At the same time, through comprehensive monitoring of the surface state of the rollers, damages such as bad grooves 8, chipped grooves 9, and collapsed grooves 10 are detected and repaired in a timely manner, extending the service life of the equipment. In addition, the introduction of the water gun cleaning system effectively removes the mortar and impurities generated during the cutting process, improving the cutting quality and equipment cleanliness. In summary, the present invention provides an efficient and reliable SiC ingot cutting monitoring system and method, providing important support for the technological progress in related fields.

[0030] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process, characterized in that: It includes a cutting module, a detection module and a cleaning module; the cutting module includes a cutting platen (4), resin strips (12) and a cutting wire mesh (5). The cutting platen (4) is used to fix the SiC ingot (13). The resin strips (12) are arranged at both ends of the cutting platen (4) to enhance the fixing effect. The cutting wire mesh (5) is connected to two rollers (3) and maintains a stable state through a preset tension; the detection module includes a CCD contour recognition system and a laser displacement sensor (27). The CCD contour recognition system consists of a guide rail screw (20), a CCD contour recognition camera (21) and a laser calibration probe (22). The laser displacement sensor (27) is installed above the cutting wire mesh (5); the cleaning module includes a water gun system, and the water gun system consists of a water supply pipe (17), a water return pipe (18) and a flow guide cover (19).

2. The wire breakage detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: The cutting platen (4) is made of a rigid material, its surface flatness is Ra≤0.5μm, and its size is designed to be 150mm±0.2mm in length and 65mm±5mm in width.

3. A wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process as described in claim 2, characterized in that: The width of the resin strip (12) is 15mm and the thickness is 3mm.

4. A wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: The tension range of the cutting wire mesh (5) is set to 15N to 30N, and the cutting speed range is 0.5m / s to 2m / s.

5. A wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: The resolution of the CCD contour recognition camera (21) is 5MP, the magnification is 5× to 10×, and the working distance is 50mm to 500mm.

6. The wire breakage detection and roller surface condition monitoring system based on the SiC ingot cutting process as described in claim 5, wherein: The laser calibration probe (22) is arranged beside the CCD contour recognition camera (21) and is used for auxiliary calibration to improve the detection accuracy.

7. The wire breakage detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: The measurement range of the laser displacement sensor (27) is ±5μm, the detection angle is set to 25°, the working wavelength is 650nm±10nm, and the measurement accuracy is 0.01mm.

8. The wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: The water supply pressure of the water gun system is set to 0.3MPa to 0.5MPa, the water flow rate is 5ml / s to 15ml / s, and the flow guide cover (19) guides the water flow to optimize the cleaning effect.

9. A wire break detection and roller surface condition monitoring system based on the SiC ingot cutting process according to claim 1, characterized in that: It also includes a PLC controller. The PLC controller receives data from the CCD contour recognition system and the laser displacement sensor (27), and judges whether to trigger an alarm or start the cleaning module according to a preset algorithm.

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