Band saw guillotine shear cooling device capable of reducing crystal ingot edge breakage

Abstract

The invention relates to the technical field of semiconductor processing, in particular to a band saw guillotine shear cooling device capable of reducing crystal ingot edge breakage, which comprises a water tank, a water inlet pipeline and a water outlet pipeline, the water outlet pipeline is provided with a water temperature detection element used for detecting the water outlet temperature, the water tank is provided with a heating element used for increasing the water temperature, and the water inlet pipeline is provided with an electromagnetic valve. The water temperature detection element, the heating element and the electromagnetic valve are all controlled by the control unit; the heating element is opened when the outlet water temperature is lower than the lower limit of a first preset temperature range and is closed when the outlet water temperature reaches the upper limit of the first preset temperature range; the electromagnetic valve is opened when the outlet water temperature reaches the upper limit of the second preset temperature range or the water volume in the water tank reaches the lower limit, and is closed when the outlet water temperature reaches the lower limit of the second preset temperature range or the water volume reaches the upper limit.

Description

Technical Field

[0001] The present invention relates to the technical field of semiconductor processing, and in particular to a cooling device for a band saw cutter capable of reducing edge collapse of a crystal ingot. Background Art

[0002] As a key supporting material for the modern information society, single crystal ingots are one of the world's most important semiconductor front-end materials and the primary functional material for the development of computers and integrated circuits. They are obtained by cutting rounded single crystal silicon rods to the desired length. Semiconductor band saw cutting machines are the primary equipment used in this cutting process.

[0003] In actual production, edge collapse may occur during the cutting process of single crystal silicon rods, which increases the time consumption of the cutting process and the yield of single crystal ingots. One of the important influencing parameters that lead to edge collapse is the cooling water temperature of the saw belt. Too high or too low temperature will cause abnormal vibration of the saw belt, resulting in edge collapse of the single crystal ingot. The water temperature of the cooling water tank equipped with the band saw cutting machine is easily affected by environmental factors. For example, when the temperature is low, the temperature of the water entering the water tank is likely to be too low. When the temperature is high, the cooling water inside the water tank is affected by both the temperature and the heat radiation of the equipment inside the plant, and the cooling water temperature is likely to be too high. Therefore, it is necessary to design a cutting machine cooling device to keep the cooling water in the appropriate temperature range and reduce the edge collapse of the crystal ingot. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the background technology and provide a band saw cutting machine cooling device that reduces the edge collapse of the crystal ingot, which can supply cooling water of suitable temperature to the saw band to reduce the occurrence of crystal ingot edge collapse.

[0005] The technical solution of the present invention is: A cooling device for a band saw cutting machine for reducing edge collapse of an ingot comprises a water tank, a water inlet pipe and a water outlet pipe connected to the water tank, the water inlet pipe being connected to a water supply main, the outlet of the water outlet pipe supplying cooling water to the saw band, the water outlet pipe being provided with a water temperature detection element for detecting the outlet water temperature, the water tank being provided with a heating element for increasing the water temperature, and the water inlet pipe being provided with a solenoid valve; the water temperature detection element, the heating element, and the solenoid valve being all controlled by a control unit; The heating element is configured to turn on when the outlet water temperature is lower than the lower limit of the first preset temperature range, and to turn off when the outlet water temperature reaches the upper limit of the first preset temperature range; The solenoid valve is configured to open when the outlet water temperature reaches the upper limit of the second preset temperature range or the water volume in the water tank reaches the lower limit, and to close when the outlet water temperature reaches the lower limit of the second preset temperature range or the water volume reaches the upper limit.

[0006] Preferably, the water temperature detection element is a thermometer with an output function, or a temperature sensor equipped with a temperature display element.

[0007] Preferably, the water tank is provided with an overflow pipe.

[0008] Preferably, the outlet of the water outlet pipe is connected to the front and rear groups of graphite blocks of the saw band, each group has two graphite blocks, which clamp the saw band from the inside and outside directions respectively, and each graphite block is provided with a water outlet hole connected to the water outlet pipe on the side close to the saw band.

[0009] Preferably, when the outlet water temperature reaches the upper limit of the third preset temperature range, cooling material is added to the water tank to reduce the cooling water in the water tank to within the third preset temperature range.

[0010] Preferably, the water tank is provided with a cooling module, which is turned on when the outlet water temperature reaches the upper limit of the third preset temperature range and is turned off when the outlet water temperature reaches the lower limit of the third preset temperature range.

[0011] The present invention has the following beneficial effects: (1) The outlet water temperature is monitored in real time through the water temperature detection element, and the cooling water temperature can be displayed in real time, so that workers can judge the cooling condition of the saw blade more intuitively; (2) The control unit can control the water inlet pipe to implement water replenishment and cooling or control the heating element to heat the cooling water according to the detected water outlet temperature, ensuring that the temperature is always maintained within the appropriate range; (3) The cooling water temperature is always kept within the appropriate range, so that the saw belt is in normal production state, which can effectively reduce the occurrence of edge collapse, thereby shortening the processing time of the cutting process and saving costs.

[0012] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following is a brief introduction to the drawings required for use in the embodiments of the present invention. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 It is a schematic structural diagram of a cooling device provided by an embodiment of the present invention.

[0015] Figure 2 This is one of the schematic diagrams of the arrangement structure of the water outlet pipe, graphite block and saw belt in an embodiment of the present invention.

[0016] Figure 3This is the second schematic diagram (top view) of the arrangement structure of the water outlet pipe, graphite block and saw blade in an embodiment of the present invention.

[0017] Reference numerals: water supply main 1, water inlet pipe 2, solenoid valve 3, water tank 4, overflow pipe 5, heating element 6, water supply pump 7, thermometer 8, water outlet pipe 9, graphite block 10, saw belt 11, wheel 12, rotating shaft 13, ingot 14. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0019] In the description of the present invention, it should be understood that the orientations or positional relationships indicated by terms such as "longitudinal", "transverse", "upper", "lower", "vertical", "horizontal", "top", and "bottom" are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, they cannot be understood as limiting the present invention.

[0020] Example 1 In this embodiment, the maximum temperature of the water supplied from the water supply main 1 will not exceed the upper limit of the optimal temperature range of the cooling water.

[0021] like Figures 1 to 3 As shown, this embodiment provides a cooling device for a band saw cutter that reduces ingot edge collapse. It is primarily used to cool a saw band 11 during single crystal ingot processing. The device comprises a water tank 4, an inlet pipe 2, and an outlet pipe 9 connected to the water tank 4. The inlet pipe 2 is connected to a water supply main 1, and the outlet of the outlet pipe 9 supplies cooling water to the saw band 11. An overflow pipe 5 is provided above the water tank 4. In one embodiment, the water tank 4 is equipped with a sensor component for detecting the upper and lower water level limits.

[0022] The water outlet pipe 9 is provided with a water supply pump 7 for detecting the water temperature of the outlet water, the water tank 4 is provided with a heating element 6 (such as an electric heating tube) for increasing the water temperature, and the water inlet pipe 2 is provided with a solenoid valve 3; the sensing component, water temperature detection element, heating element 6, water supply pump 7 and solenoid valve 3 are all controlled by the control unit of the band saw cutting machine, and can work in coordination with the rest of the band saw cutting machine.

[0023] The heating element 6 is configured to turn on when the outlet water temperature is lower than the lower limit of the first preset temperature range, and to turn off when it reaches the upper limit of the first preset temperature range, so that the outlet water temperature is maintained within the set range.

[0024] The solenoid valve 3 is configured to connect the water inlet pipe 2, allowing water from the water supply main 1 to enter the water tank 4. The opening and closing of the solenoid valve 3 is related to the water level in the water tank 4 and the outlet water temperature. When the sensor detects that the water level in the water tank 4 has reached the lower limit, the solenoid valve 3 opens to replenish water in the water tank 4. When the water level reaches the upper limit, the solenoid valve 3 closes. When the outlet water temperature reaches the upper limit of a second preset temperature range, the solenoid valve 3 opens to replenish water in the water tank 4 for cooling. When the outlet water temperature reaches the lower limit of the second preset temperature range, the solenoid valve 3 closes.

[0025] In this embodiment, the values ​​of the first preset temperature range and the second preset temperature range are determined according to actual production conditions and are both within the optimal temperature range of cooling water. The first preset temperature range can be completely identical to or partially overlap with the second preset temperature range.

[0026] In one embodiment, the water temperature detection element is a thermometer 8 with an output function, and the detected water outlet temperature data is output to the control unit. The scale of the thermometer 8 can display the water temperature. In another embodiment, the water temperature detection element adopts a temperature sensor equipped with a temperature display element, and the water outlet temperature data detected by the temperature sensor is output to the control unit.

[0027] The saw band 11 is wound around two wheels 12, each mounted on a rotating shaft 13. The rotating shaft 13 of at least one wheel 12 serves as the driving shaft. The outlet of the water outlet pipe 9 is connected to two groups of graphite blocks 10 at the front and rear of the saw band 11. The area between the two groups of graphite blocks 10 is the working section where the saw band 11 cuts the ingot 14. Each group of graphite blocks 10 contains two graphite blocks, one on the inner and outer sides of the saw band 11. Each graphite block 10 is provided with at least one water outlet hole connected to the water outlet pipe 9. The water outlet hole is preferably located on the side of the graphite block 10 facing the saw band 11. Cooling water flows out of the water outlet hole and cools the saw band 11.

[0028] The working principle of this embodiment is: (1) When the ambient temperature around the water tank 4 is suitable, the outlet water temperature of the outlet pipe 9 can always be maintained within the optimal temperature range. The solenoid valve 3 only needs to be opened when the water volume in the water tank 4 reaches the lower limit, and the water inlet pipe 2 is connected to the water supply main 1 to replenish water to the water tank 4. When the water volume reaches the upper limit, the solenoid valve 3 is closed; (2) When the water tank 4 is affected by the ambient temperature and the internal water temperature rises, and the water temperature detection element detects that the outlet water temperature is too high (reaches the upper limit of the second preset temperature range), the control unit controls the solenoid valve 3 to open and replenish water into the water tank 4. Since the incoming water temperature from the water supply main 1 is lower than the water temperature in the water tank 4, the water replenishment can achieve a cooling effect; When the outlet water temperature reaches the lower limit of the second preset temperature range, the solenoid valve 3 is closed. If the incoming water temperature of the water supply main 1 is higher than the lower limit of the second preset temperature range, the solenoid valve 3 may also be closed when the water volume in the water tank 4 reaches the upper limit. (3) When the water temperature of the water tank 4 and the water supply main 1 is affected by the ambient temperature and the internal water temperature is low (lower than the lower limit of the first preset temperature range), the heating element 6 is turned on to heat the water in the water tank 4. When the upper limit of the first preset temperature range is reached, the heating element 6 is turned off.

[0029] Example 2 This embodiment is mainly aimed at the situation where the water supply temperature of the water supply main 1 is relatively high and only using the water supply main 1 to replenish the water tank 4 is insufficient to reduce the outlet water temperature to the optimal temperature range.

[0030] Based on the embodiment 1, this embodiment forcibly cools the cooling water in the water tank 4 by providing a cooling module at the water tank 4, and the cooling module is controlled by the control unit. Figure 1 The intermediate cooling module is omitted.

[0031] The cooling module can adopt an existing module. In one embodiment, the cooling module adopts a semiconductor refrigeration plate (also called a thermoelectric refrigeration plate) arranged on the four walls of the water tank. In another embodiment, the cooling module is an evaporator of a refrigeration device. In another embodiment, the cooling module is a cold pipe connected to the refrigeration device.

[0032] The cooling module is configured to operate as follows: it turns on when the outlet water temperature reaches the upper limit of a third preset temperature range, and turns off when it reaches the lower limit. The third preset temperature range is set based on actual production scenarios and falls within the optimal temperature range for cooling water.

[0033] The working principle of this embodiment is: when the water supply main 1 reaches the upper limit of the third preset temperature range, the water replenishment is insufficient to meet the cooling requirements. At this time, the control unit starts the cooling module and performs rapid cooling processing until the water temperature reaches the lower limit of the third preset temperature range and the cooling module is turned off.

[0034] In another embodiment, when the outlet water temperature reaches the upper limit of the third preset temperature range, a certain amount of cooling material is added to the water tank to reduce the cooling water in the water tank to within the third preset temperature range. The amount of cooling material and the time interval for addition are set according to the actual production scenario. The cooling material can be selected according to the production scenario, such as ice cubes, stainless steel ice particles, low-temperature water or other low-temperature liquids. The selection of the low-temperature liquid must be based on the premise that it does not react with the water tank, pipes, saw belts, ingots, etc. The specific temperature of the low-temperature water is selected according to the production scenario, for example, water below 10°C.

[0035] In the above-mentioned embodiment 1 and embodiment 2, the water supply temperature of the water supply main 1 can be obtained by setting a temperature measuring component on the water supply main 1 or the water inlet pipe 2, or the control unit obtains it by exchanging data with the water supply system.

[0036] The above description is merely a preferred embodiment of the present invention. For those skilled in the art, the present invention may be modified and varied in various ways. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of protection of the present invention.

Claims

1. A cooling device for a band saw cutting machine for reducing edge collapse of an ingot, comprising a water tank (4), a water inlet pipe (2) and a water outlet pipe (9) connected to the water tank (4), wherein the water inlet pipe (2) is connected to a water supply main (1), and the outlet of the water outlet pipe (9) supplies cooling water to a saw band (11), and is characterized in that: The water outlet pipe (9) is provided with a water temperature detection element for detecting the outlet water temperature, the water tank (4) is provided with a heating element (6) for increasing the water temperature, and the water inlet pipe (2) is provided with a solenoid valve (3); The water temperature detection element, the heating element (6) and the solenoid valve (3) are all controlled by a control unit; The heating element (6) is configured to turn on when the outlet water temperature is lower than the lower limit of a first preset temperature range, and to turn off when the outlet water temperature reaches the upper limit of the first preset temperature range; The solenoid valve (3) is configured to open when the outlet water temperature reaches the upper limit of the second preset temperature range or the water volume in the water tank (4) reaches the lower limit, and to close when the outlet water temperature reaches the lower limit of the second preset temperature range or the water volume reaches the upper limit.

2. A cooling device for a band saw cutter for reducing edge collapse of an ingot according to claim 1, characterized in that: The water temperature detection element is a thermometer (8) with an output function, or a temperature sensor equipped with a temperature display element.

3. A cooling device for a band saw cutter for reducing edge collapse of an ingot according to claim 1, characterized in that: The water tank (4) is provided with an overflow pipe (5).

4. A cooling device for a band saw cutter for reducing edge collapse of an ingot according to any one of claims 1 to 3, characterized in that: The outlet of the water outlet pipe (9) is connected to the front and rear groups of graphite blocks (10) of the saw band (11), each group having two graphite blocks (10) arranged on the inner and outer sides of the saw band (11), respectively. Each graphite block (10) is provided with a water outlet hole connected to the water outlet pipe (9), and cooling water flows out of the water outlet hole and cools the saw band (11).

5. A cooling device for a band saw cutter for reducing edge collapse of an ingot according to any one of claims 1 to 3, characterized in that: When the outlet water temperature reaches the upper limit of the third preset temperature range, cooling material is added to the water tank (4) to reduce the cooling water in the water tank (4) to within the third preset temperature range.

6. A cooling device for a band saw cutter for reducing edge collapse of an ingot according to any one of claims 1 to 3, characterized in that: The water tank (4) is provided with a cooling module, which is turned on when the outlet water temperature reaches the upper limit of the third preset temperature range, and is turned off when the outlet water temperature reaches the lower limit of the third preset temperature range.

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