Device and method for reducing material lifting load of slicing machine and improving silicon wafer quality

Abstract

The invention provides a device and method for reducing material lifting load of a slicing machine and improving silicon wafer quality, the device comprises a pressure regulating device, a pressure detecting device and a control device, a water inlet of the pressure regulating device is connected with a water inlet pipeline, a water outlet of the pressure regulating device is connected with a spraying device, the pressure detecting device is arranged at a water outlet of the spraying device, and the control device is connected with the pressure regulating device. The pressure detection device and the pressure regulating device are respectively connected with the control device, the pressure detection device detects the pressure of the water outlet of the spraying device, and the control device receives a signal transmitted by the pressure detection device and controls the pressure regulating device to act according to the signal so as to regulate the spraying pressure of the spraying device. The device has the beneficial effects that every two silicon wafers can be dispersed by increasing the spraying pressure and depending on the tension of water, and under the condition that the spraying pressure meets the process conditions, the silicon wafers which are adsorbed in pairs are dispersed by online liquid, so that the viscous friction between a cutting tool (diamond wire) and the silicon wafers is reduced, the abnormal rate of material lifting is reduced, and the quality of the silicon wafers is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of silicon wafer production, and in particular relates to a device and method for reducing the material lifting load of a slicer and improving the quality of silicon wafers. Background Art

[0002] During the silicon rod cutting process in the photovoltaic industry, cutting fluid is an auxiliary consumable product that must be used in the silicon wafer cutting process. During the cutting process, due to the tension on the surface of the slice, the two silicon wafers will be adsorbed to each other. When the silicon rod length is certain, when the silicon wafer thickness is less than 130 microns, the adsorption force between the silicon wafers is greater due to the smaller wire spacing, which makes it difficult to take out the cutting tool (diamond wire) during the material lifting process after the cutting is completed. This will cause the spindle to stop and alarm due to overload, cut the wire mesh during material lifting, and break the wire during the material lifting process, resulting in increased loss of the cutting tool (diamond wire) and reduced silicon wafer yield. Summary of the Invention

[0003] In view of the above problems, the present invention provides a device and method for reducing the material lifting load of a slicer and improving the quality of silicon wafers, so as to solve the above or other problems existing in the prior art.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a device for reducing the material lifting load of a slicer and improving the quality of silicon wafers, including a pressure regulating device, a pressure detecting device and a control device, the water inlet of the pressure regulating device is connected to the water inlet pipeline, the water outlet of the pressure regulating device is connected to the spraying device, the pressure detecting device is arranged at the water outlet of the spraying device, the pressure detecting device and the pressure regulating device are respectively connected to the control device, the pressure detecting device detects the pressure of the water outlet of the spraying device, the control device receives the signal transmitted by the pressure detecting device and controls the action of the pressure regulating device according to the signal, and adjusts the spraying pressure of the spraying device.

[0005] Furthermore, the pressure regulating device is a pressure regulating pump.

[0006] Furthermore, the control device is a frequency converter.

[0007] Furthermore, the pressure detection device is a pressure sensor.

[0008] A method for reducing the material lifting load of a slicer and improving the quality of silicon wafers. In the material lifting process, the material is lifted in stages. As the feed position gradually decreases, the feed speed, cutting fluid flow rate and spray pressure in different stages are controlled differently.

[0009] Furthermore, the feed speed, cutting fluid flow rate and spray pressure in the latter stage are greater than those in the former stage.

[0010] Furthermore, the material lifting process includes two stages. In the first stage of material lifting, as the feed position gradually decreases, the feed speed is controlled to be the first feed speed, the cutting fluid flow is controlled to be the first flow, and the spray pressure is controlled to be the first pressure.

[0011] Furthermore, in the second stage of material feeding, as the feed position gradually decreases, the feed speed is controlled to be the second feed speed, the cutting fluid flow rate is controlled to be the second flow rate, and the spraying pressure is controlled to be the second pressure.

[0012] Furthermore, during the first stage of feeding, based on the silicon rod cutting position, the feeding position is reduced from 230 mm to 210 mm, the first feeding speed is 20-30 mm / min, the first flow rate is 220-230 L / min, and the first pressure is 2500-2600 mmPa.

[0013] Furthermore, during the second stage of material feeding, based on the end position of the first stage of material feeding, the feeding position is reduced from 210 mm to 0 mm, the second feeding speed is 40-50 mm / min, the second flow rate is 260-270 L / min, and the first pressure is 4000-4100 mmPa.

[0014] Due to the adoption of the above technical solution, a pressure regulating device is provided between the spray device and the water inlet pipeline to regulate the water spraying pressure of the spray device, and a pressure detecting device is provided at the water outlet of the spray device to detect the pressure of the water outlet of the spray device. The control device receives the pressure value detected by the pressure detecting device and controls the operation of the pressure regulating device according to the pressure value. According to the demand of the spraying pressure, a preset pressure value can be set in the control device. According to the preset pressure value and the detected pressure value, the operation of the pressure regulating device is controlled to adjust the spraying pressure of the spray device. By increasing the spraying pressure, the silicon wafers can be dispersed in pairs by relying on the tension of the water. When the spraying pressure meets the process conditions, the online liquid disperses the adsorbed silicon wafers in pairs, thereby reducing the viscous friction between the cutting tool (diamond wire) and the silicon wafer, and at the same time reducing the spindle load torque acted by the cutting tool (diamond wire), thereby increasing the service life of the spindle motor and the bearing box, reducing the abnormal rate of material lifting, and improving the quality of the silicon wafers. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural diagram of an embodiment of the present invention.

[0016] In the picture:

[0017] 1. Pressure regulating device 2. Pressure detection device 3. Feed spray device

[0018] 4. Single crystal spray device 5. Grooved wheel spray device DETAILED DESCRIPTION

[0019] The present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0020] Figure 1 A structural schematic diagram of an embodiment of the present invention is shown. This embodiment relates to a device and method for reducing the material lifting load of a slicer and improving the quality of silicon wafers. It is used to control the spray pressure of a spray device during the material lifting process of the slicer after slicing is completed. A pressure regulating device is provided to adjust the spray pressure according to the spray pressure requirements, disperse the silicon wafers adsorbed in pairs, reduce the viscous friction between the cutting tool (diamond wire) and the silicon wafer, and at the same time reduce the spindle load torque acted by the cutting tool (diamond wire), thereby reducing the abnormal rate of material lifting.

[0021] A device for reducing the loading of a slicer and improving the quality of silicon wafers, such as Figure 1 As shown, it is installed between the spray device and the water inlet pipeline, and includes a pressure regulating device 1, a pressure detection device 2 and a control device. Among them, the pressure regulating device 1 is used to adjust the spray pressure of the spray device. The water inlet of the pressure regulating device 1 is connected to the water inlet pipeline, and the water outlet of the pressure regulating device 1 is connected to the spray device through a connecting pipe. The liquid in the water inlet pipeline enters the spray device through the pressure regulating device 1. The spray device sprays the liquid, spraying it on the silicon wafer after cutting, and also spraying it on the feed point and the groove wheel;

[0022] The pressure detection device 2 is provided at the water outlet of the spray device and is used to detect the pressure at the water outlet of the spray device;

[0023] The pressure detection device 2 and the pressure regulating device 1 are respectively connected to the control device. The control device receives the pressure value detected by the pressure detection device 2, and controls the action of the pressure regulating device 1 according to the pressure value detected by the pressure detection device 2 to adjust the spraying pressure of the spraying device.

[0024] In the material lifting process, when the cut silicon wafers are sprayed, the pressure detection device 2 detects the pressure at the water outlet of the spray device. The control device receives the pressure detection value and controls the action of the pressure regulating device 1 according to the pressure detection value to adjust the spraying pressure of the spray device.

[0025] The above-mentioned spraying device includes a knife feed spraying device 3, a single crystal spraying device 4 and a groove wheel spraying device 5. The inlet end of the knife feed spraying device 3, the inlet end of the single crystal spraying device 4 and the inlet end of the groove wheel spraying device 5 are connected and communicated with the water outlet of the pressure regulating device 1 through a four-way connection. The water outlet of the knife feed spraying device 3 corresponds to the knife feed of the slicer, and sprays the knife feed. The water outlet of the single crystal spraying device 4 corresponds to the single crystal cutting position, and sprays the single crystal cutting position (the silicon wafer after cutting). The water outlet of the groove wheel spraying device 5 corresponds to the groove wheel, and sprays the groove wheel. Pressure detection devices 2 are installed at the water outlet of the feed spray device 3, the water outlet of the single crystal spray device 4 and the water outlet of the groove wheel spray device 5, which respectively detect the water outlet pressures at the water outlet of the feed spray device 3, the water outlet of the single crystal spray device 4 and the water outlet of the groove wheel spray device 5. The pressure detection device 2 at the water outlet of the feed spray device 3, the pressure detection device 2 at the water outlet of the single crystal spray device 4 and the pressure detection device 2 at the water outlet of the groove wheel spray device 5 are all connected to the control device to transmit the detected pressure information to the control device.

[0026] The pressure regulating device 1 is a pressure regulating pump, which is a commercially available product and can be selected according to actual needs;

[0027] The control device mentioned above is a frequency converter, which is a commercially available product and can be selected according to actual needs;

[0028] The pressure detection device 2 is a pressure sensor, which is a commercially available product and can be selected according to actual needs. When the device for reducing the material loading load of the slicer and improving the quality of silicon wafers is used, during the material loading process, the spray device sprays the cut silicon wafers, the blade feed, and the groove wheel. According to the requirements of the spray system, a preset pressure value is preset in the control device. When the spray device sprays liquid, the pressure detection device 2 constantly detects the pressure at the water outlet of the spray device and transmits the detected pressure value to the control device. The control device compares the detected pressure value with the preset pressure value. When the detected pressure value is less than the preset pressure value, the control device controls the pressure regulating device 1 to operate, increase the pressure at the water outlet of the spray device, and then increase the spray pressure of the spray device, so that the water outlet pressure of the spray device increases. If the detected pressure value is greater than the preset pressure value, the control device controls the pressure regulating device 1 to stop operating and maintain the spray pressure of the spray device. In this way, the spray pressure of the spray device is controlled and stabilized, and the silicon wafers adsorbed together are dispersed.

[0029] By pressurizing the liquid in the pipeline between the pressure regulating device 1 and the spraying device and adjusting the pressure required by the system, the pressure regulating device 1 can provide a certain pressure through the pressure regulating function of the pressure regulating device 1. When the pressure exceeds the range, the control device will control the pressure regulating device 1 to stop running. If the pressure is too low, the control device will control the pressure regulating device 1 to start, so as to provide a stable spray liquid supply pressure, thereby solving the problems of insufficient spray pressure in the pipeline during the material lifting process, slice adsorption, and spindle load over-limit alarm shutdown and cutting of the wire mesh for material lifting.

[0030] In some feasible embodiments, the liquid may be a cutting fluid.

[0031] A method for reducing the material lifting load of a slicer and improving the quality of silicon wafers, using the above-mentioned device for reducing the material lifting load of a slicer and improving the quality of silicon wafers to adjust the pressure of the pipeline system of a spray device in the slicer, providing a stable spray liquid supply pressure for the spray device, and maintaining the spray pressure of the spray device stable; after the silicon wafer is cut, in the cutting process, the material is lifted in stages, and the feed speed, cutting liquid flow rate and spray pressure are controlled differently in different stages as the feed position gradually decreases, and the feed speed, cutting liquid flow rate and spray pressure in the latter stage are all increased compared with the previous stage.

[0032] Specifically, the material lifting process includes two stages. The first stage is the middle section where the diamond wire comes out of the resin plate and the silicon wafer, and the second stage is the diamond wire coming out of the knife section. For the same adsorption force between two adjacent silicon wafers, the adsorption force between the two adjacent silicon wafers in the knife section is greater than the adsorption force between the two adjacent silicon wafers in the middle section. Therefore, it is necessary to increase the flow rate and spray pressure of the cutting fluid in the knife section to disperse the silicon wafers that are adsorbed together.

[0033] During the first stage of material feeding, as the feed position gradually decreases, the feed speed is controlled to be the first feed speed, the cutting fluid flow rate is controlled to be the first flow rate, and the spraying pressure is controlled to be the first pressure.

[0034] The above-mentioned first feed speed is 20-30 mm / min, which is selected according to actual needs and no specific requirements are made here.

[0035] The above-mentioned first flow rate is 220-230L / min, which is selected according to actual needs. No specific requirements are made here.

[0036] The above-mentioned first pressure is 2500-2600 mmPa, which is selected according to actual needs and no specific requirements are made here.

[0037] During the first stage of material feeding, the feeding position is reduced from 230 mm to 210 mm based on the silicon rod cutting-through position (the contact position between the diamond wire and the resin plate).

[0038] In the second stage of material feeding, as the feed position gradually decreases, the feed speed is controlled to be the second feed speed, the cutting fluid flow rate is controlled to be the second flow rate, and the spraying pressure is controlled to be the second pressure.

[0039] The above-mentioned second feed speed is 40-50 mm / min, which is selected according to actual needs and no specific requirements are made here.

[0040] The above-mentioned second flow rate is 260-270L / min, which is selected according to actual needs. No specific requirements are made here.

[0041] The above-mentioned second pressure is 4000-4100 mmPa, which is selected according to actual needs and no specific requirements are made here.

[0042] During the first stage of material lifting, the feed position is reduced from 210 mm to 0 mm based on the end position of the first stage of material lifting.

[0043] In some feasible embodiments, as shown in the table below, the material feeding process includes two stages. In each stage, as the feed position decreases, the feed speed, cutting fluid flow rate, and spray pressure remain unchanged. As the two stages proceed, the feed speed, cutting fluid flow rate, and spray pressure gradually increase. The specific parameters are:

[0044]

[0045]

[0046] Due to the adoption of the above technical solution, a pressure regulating device is provided between the spray device and the water inlet pipeline to regulate the water spraying pressure of the spray device, and a pressure detecting device is provided at the water outlet of the spray device to detect the pressure at the water outlet of the spray device. The control device receives the pressure value detected by the pressure detecting device and controls the operation of the pressure regulating device according to the pressure value. According to the demand of the spraying pressure, a preset pressure value can be set in the control device. According to the preset pressure value and the detected pressure value, the operation of the pressure regulating device is controlled to adjust the spraying pressure of the spray device. By increasing the spraying pressure, the silicon wafers can be dispersed in pairs by relying on the tension of the water. When the spraying pressure meets the process conditions, the online liquid disperses the adsorbed silicon wafers in pairs, thereby reducing the viscous friction between the cutting tool (diamond wire) and the silicon wafer, and at the same time reducing the spindle load torque acted by the cutting tool (diamond wire), thereby increasing the service life of the spindle motor and the bearing box, reducing the abnormal rate of material lifting, and improving the quality of the silicon wafers.

[0047] The embodiments of the present invention are described in detail above, but the contents described are only preferred embodiments of the present invention and should not be considered to limit the scope 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 device for reducing the loading load of a slicer and improving the quality of silicon wafers, characterized by: It includes a pressure regulating device, a pressure detecting device and a control device. The water inlet of the pressure regulating device is connected to the water inlet pipeline, the water outlet of the pressure regulating device is connected to the spraying device, the pressure detecting device is arranged at the water outlet of the spraying device, the pressure detecting device and the pressure regulating device are respectively connected to the control device, the pressure detecting device detects the pressure of the water outlet of the spraying device, the control device receives the signal transmitted by the pressure detecting device and controls the action of the pressure regulating device according to the signal, thereby adjusting the spraying pressure of the spraying device.

2. The device for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 1, characterized in that: The pressure regulating device is a pressure regulating pump.

3. The device for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 1 or 2, characterized in that: The control device is a frequency converter.

4. The device for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 3, characterized in that: The pressure detection device is a pressure sensor.

5. A method for reducing the loading of a slicer and improving the quality of silicon wafers, characterized by: In the material lifting process, the material is lifted in stages. As the feed position gradually decreases, the feed speed, cutting fluid flow rate and spray pressure in different stages are controlled differently.

6. The method for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 5, characterized in that: The feed speed, cutting fluid flow rate and spray pressure in the latter stage are greater than those in the former stage.

7. The method for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 5 or 6, characterized in that: The material raising process includes two stages. In the first stage of material raising, as the feed position gradually decreases, the feed speed is controlled to be the first feed speed, the cutting fluid flow is controlled to be the first flow, and the spraying pressure is controlled to be the first pressure.

8. The method for reducing the slicer loading and improving the quality of silicon wafers according to claim 7, characterized in that: In the second stage of material feeding, as the feed position gradually decreases, the feed speed is controlled to be the second feed speed, the cutting fluid flow rate is controlled to be the second flow rate, and the spraying pressure is controlled to be the second pressure.

9. The method for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 7, characterized in that: During the first stage of material feeding, based on the silicon rod cutting-through position, the feeding position is reduced from 230 mm to 210 mm, the first feeding speed is 20-30 mm / min, the first flow rate is 220-230 L / min, and the first pressure is 2500-2600 mmPa.

10. The method for reducing the material loading of a slicer and improving the quality of silicon wafers according to claim 8 or 9, characterized in that: In the second stage of material lifting, based on the end position of the first stage of material lifting, the feeding position is reduced from 210mm to 0mm, the second feeding speed is 40-50mm / min, the second flow rate is 260-270L / min, and the first pressure is 4000-4100mmPa.

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