Cooling disc body and preparation method thereof

Abstract

The invention relates to a cooling disc body and a preparation method thereof. The cooling disc body comprises a runner main body and a cover plate matched with the runner main body, the runner main body is provided with a first spiral runner and a second spiral runner, the first spiral runner and the second spiral runner are wound at intervals, the head ends of the first spiral runner and the second spiral runner are mutually independent, and the tail ends of the first spiral runner and the second spiral runner are mutually communicated; and the wall thickness of a bottom plate of the runner main body is 1-1.2 mm. The first spiral flow channel and the second spiral flow channel are coiled in the flow channel main body at intervals, and a cooling medium can be injected at the same time, so that rapid cooling is realized; and by designing a proper wall thickness of the bottom plate, the time required for cooling the wafer is further shortened, and the use performance of the cooling disc body is enhanced.

Description

Technical Field

[0001] The invention relates to the technical field of wafer cooling, and in particular to a cooling plate and a preparation method thereof. Background Art

[0002] Semiconductor back-end equipment usually needs to operate in a high-temperature environment, so the equipment needs to be cooled and the temperature needs to be precisely controlled to ensure that it can meet the requirements of long-term stable operation. The cooling plate is a cooling device for the wafer. It uses the contact surface with the wafer as the use surface. There is a flow channel inside, which can be flushed with medium for cooling. The heat of the wafer is taken away by the water channel, thereby playing a role in cooling.

[0003] At present, the finished cooling disc body has the problems of large wall thickness, small flow channel width and large thickness of the use surface, which will lead to a decrease in cooling rate and cooling effect. CN 106354195A discloses a cooling disc device for semiconductor equipment, including a first cooling disc body, a second cooling disc body, a semiconductor cooling plate and a spring clamping mechanism, wherein the first cooling disc body and the second cooling disc body are connected by multiple spring clamping mechanisms and sealed at the edges, and the semiconductor cooling plate is arranged in a sealed cavity between the first cooling disc body and the second cooling disc body. A relative position fixing device is provided near each of the spring clamping mechanisms. The invention can increase the service life of the cooling disc structure, but the cooling effect of the cooling plate compared to the cooling fluid medium needs to be improved.

[0004] CN 201011654A discloses a cooling plate structure, which has an upper plate, a lower plate and a cooling device, specifically a semiconductor refrigeration module structure is sandwiched between the upper plate and the lower plate, and a silicone grease layer is sandwiched between the semiconductor refrigeration module and the upper plate and between the semiconductor refrigeration module and the lower plate, respectively. A PT100 temperature sensor is embedded in the upper plate, and a sealing silicone layer is coated on the outer side surfaces of the upper and lower plates; in addition, a cooling water pipe is arranged in the lower plate. In the invention, the silicone layer is used for sealing, which is prone to cracking, resulting in a problem of reduced product service life.

[0005] CN 109817544A discloses a semiconductor equipment heating and cooling composite disk device, including a hot disk heating zone, a composite disk frame, a cooling disk, a cooling zone lifting mechanism, a cooling disk conveying mechanism, a hot disk zone lifting mechanism and a cooling disk zone, wherein the hot disk heating zone and the cooling disk zone are arranged in the composite disk frame, the hot disk zone lifting mechanism is arranged in the hot disk heating zone, the cooling zone lifting mechanism and the cooling disk conveying mechanism are both arranged in the cooling disk zone, the cooling disk is arranged on the cooling disk conveying mechanism, the cooling disk conveying mechanism is used to convey the cooling disk between the cooling disk zone and the hot disk heating zone, and the cooling zone lifting mechanism is used to receive the wafer. However, the cooling disk provided by the invention still has the problem of insufficient welding sealing during the welding process, and the thick surface of the disk body after welding leads to reduced cooling effect.

[0006] Therefore, in view of the shortcomings of the prior art, there is an urgent need to provide a cooling disk body with good cooling effect, excellent performance and long service life. Summary of the invention

[0007] The purpose of the present invention is to provide a cooling plate body and a preparation method thereof. By adjusting the structure of the cooling plate body and reducing the thickness of the use surface, the desoldering caused by welding problems can be eliminated while ensuring the cooling effect and causing water leakage.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a cooling plate, the cooling plate comprising a flow channel body and a cover plate matched with the flow channel body; the flow channel body is provided with a first spiral flow channel and a second spiral flow channel, the first spiral flow channel and the second spiral flow channel are arranged in a spiral manner with an interval, the first ends of the first spiral flow channel and the second spiral flow channel are independent of each other, and the ends are connected to each other;

[0010] The bottom plate wall thickness of the flow channel body is 1-1.2 mm.

[0011] The cooling plate provided by the present invention has a first spiral flow channel and a second spiral flow channel arranged in a coiled manner at intervals inside the flow channel body, and cooling medium can be injected simultaneously, thereby achieving rapid cooling and significantly improving the cooling effect; by designing a suitable bottom plate wall thickness, the time required for cooling the wafer is further reduced, thereby enhancing the performance of the cooling plate.

[0012] The bottom plate wall thickness of the flow channel body is 1-1.2 mm, for example, 1 mm, 1.05 mm, 1.1 mm, 1.15 mm or 1.2 mm, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0013] Preferably, the material of the flow channel body includes aluminum alloy.

[0014] Preferably, the first spiral flow channel and the second spiral flow channel are both structures of non-equal width.

[0015] The "non-equal width structure" means that the width of each part of the first spiral flow channel is not equal, and the width of each part of the second spiral flow channel is also not equal. The design of the non-equal width structure can improve the flow efficiency of the cooling medium, thereby improving the cooling effect of the wafer.

[0016] Preferably, the first spiral flow channel and the second spiral flow channel are both 29-31 mm at their widest points and 11-13 mm at their narrowest points.

[0017] The widest parts of the first spiral flow channel and the second spiral flow channel are both 29-31 mm, for example, 29 mm, 29.5 mm, 30 mm, 30.5 mm or 31 mm, but are not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0018] The narrowest parts of the first spiral flow channel and the second spiral flow channel are both 11-13 mm, for example, 11 mm, 11.5 mm, 12 mm, 12.5 mm or 13 mm, but are not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0019] Preferably, the height of the first spiral flow channel and the second spiral flow channel are both 3.5-4.5 mm, for example, 3.5 mm, 3.8 mm, 4 mm, 4.2 mm or 4.5 mm, but are not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0020] Preferably, reinforcing weldments are independently and spaced apart along the center lines of the first spiral flow channel and the second spiral flow channel.

[0021] Preferably, the height of the reinforcing weldment is 3.5-4.5 mm, for example, 3.5 mm, 3.8 mm, 4 mm, 4.2 mm or 4.5 mm, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0022] The provision of the reinforced welding piece can increase the contact area between the flow channel body and the cover plate, thereby improving the welding bonding effect and reducing the probability of water leakage.

[0023] In a second aspect, the present invention provides a method for preparing the cooling plate according to the first aspect, the method comprising the following steps:

[0024] (1) a first spiral flow channel and a second spiral flow channel are opened inside the flow channel body, and then the surface of the flow channel body is pickled to obtain a body to be welded;

[0025] (2) Vacuum diffusion welding is performed on the cover plate and the main body to be welded obtained in step (1), and then post-processed to obtain the cooling plate body.

[0026] The preparation method of the cooling disc provided by the present invention can effectively remove impurities and pollutants on the surface of the flow channel body by pickling the flow channel body, thereby improving the cleanliness of the surface and preventing the subsequent influence on the cooling effect of the cooling medium.

[0027] Preferably, the acid solution used for the pickling treatment in step (1) comprises a hydrofluoric acid solution with a concentration of 12-14%, for example, it can be 12%, 13% or 14%, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0028] Preferably, the pickling time in step (1) is 20-40 seconds, for example, 20 seconds, 25 seconds, 30 seconds, 35 seconds or 40 seconds, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0029] Preferably, the temperature of the vacuum diffusion welding in step (2) is 555-565°C, for example, 555°C, 558°C, 560°C, 562°C or 565°C, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0030] Preferably, the pressure of the vacuum diffusion welding in step (2) is 1.8-2.2 MPa, for example, 1.8 MPa, 1.9 MPa, 2 MPa, 2.1 MPa or 2.2 MPa, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0031] Preferably, the vacuum diffusion welding time in step (2) is 1.8-2.2 h, for example, 1.8 h, 1.9 h, 2 h, 2.1 h or 2.2 h, but is not limited to the listed values, and other values ​​not listed within the numerical range are also applicable.

[0032] Preferably, the vacuum degree of the vacuum diffusion welding in step (2) is less than 2×10 -2 Pa, for example, can be 1.8×10 - 2 Pa, 1.5×10 -2 Pa, 1.2×10 -2 Pa, 1×10 -2 Pa or 0.8×10 -2 Pa, but is not limited to the listed values, and other unlisted values ​​within the numerical range are also applicable.

[0033] The present invention uses vacuum diffusion welding to combine the flow channel body and the cover plate together, which has a short production cycle. Welding under high temperature and high pressure can make the intermolecular diffusion between the flow channel body and the cover plate active, achieve close fitting, and thus meet the use requirements.

[0034] Preferably, the post-processing in step (2) includes rough milling and fine milling.

[0035] As a preferred technical solution of the preparation method of the present invention, the preparation method comprises the following steps:

[0036] (1) a first spiral flow channel and a second spiral flow channel are opened inside the flow channel body, and then a hydrofluoric acid solution with a concentration of 12-14% is used to pickle the surface of the flow channel body for 20-40 seconds to obtain a body to be welded;

[0037] (2) Vacuum diffusion welding is performed on the cover plate and the main body to be welded obtained in step (1), wherein the vacuum diffusion welding temperature is 555-565°C, the pressure is 1.8-2.2 MPa, the time is 1.8-2.2 h, and the vacuum degree is less than 2×10 -2 Pa; and then through rough milling and fine milling, the cooling disc body is obtained.

[0038] Compared with the prior art, the present invention has the following beneficial effects:

[0039] The cooling plate body provided by the present invention has a first spiral flow channel and a second spiral flow channel arranged in a coiled manner at intervals inside the flow channel body, and a cooling medium can be injected at the same time, thereby achieving rapid cooling and significantly improving the cooling effect; by designing a suitable bottom plate wall thickness, the time required for cooling the wafer is further reduced, and the performance of the cooling plate is enhanced; by strengthening the setting of the welding parts, the welding effect of the flow channel body and the cover plate can be significantly improved, and the probability of water leakage can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 is a schematic structural diagram of a flow channel main body provided in Example 1 of the present invention;

[0041] Among them: 1, the first spiral flow channel; 2, the second spiral flow channel; 3, the strengthened welded parts. DETAILED DESCRIPTION

[0042] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0043] Example 1

[0044] This embodiment provides a cooling disc body, which includes a flow channel body and a cover plate matched with the flow channel body; the structural schematic diagram of the flow channel body is shown in Figure 1 As shown, the flow channel body is provided with a first spiral flow channel 1 and a second spiral flow channel 2, the first spiral flow channel 1 and the second spiral flow channel 2 are arranged in a coiled manner at intervals, the first spiral flow channel 1 and the second spiral flow channel 2 are independent of each other at their head ends, and the ends are connected to each other; the bottom plate wall thickness of the flow channel body is 1.1 mm; the material of the flow channel body is aluminum alloy;

[0045] The first spiral flow channel 1 and the second spiral flow channel 2 are both non-uniform width structures; the widest part of the first spiral flow channel 1 and the second spiral flow channel 2 is 30 mm, and the narrowest part is 12 mm; the height of the first spiral flow channel 1 and the second spiral flow channel 2 is 4 mm;

[0046] Reinforcement weldments 3 are independently and spaced apart along the center lines of the first spiral flow channel 1 and the second spiral flow channel 2 , and the height of the reinforcement weldments 3 is 4 mm.

[0047] The preparation method of the cooling plate comprises the following steps:

[0048] (1) a first spiral flow channel 1 and a second spiral flow channel 2 are opened inside the flow channel body, and then a surface of the flow channel body is pickled for 30 seconds using a hydrofluoric acid solution having a concentration of 13% to obtain a body to be welded;

[0049] (2) The cover plate and the main body to be welded obtained in step (1) are subjected to vacuum diffusion welding. The vacuum diffusion welding temperature is 560° C., the pressure is 2 MPa, the time is 2 h, and the vacuum degree is 1.5×10 -2 Pa; and then through rough milling and fine milling, the cooling plate body is obtained.

[0050] Example 2

[0051] The present embodiment provides a cooling plate, which comprises a flow channel body and a cover plate matched with the flow channel body; the flow channel body is provided with a first spiral flow channel 1 and a second spiral flow channel 2, the first spiral flow channel 1 and the second spiral flow channel 2 are arranged in a spiral manner, the first ends of the first spiral flow channel 1 and the second spiral flow channel 2 are independent of each other, and the ends are connected to each other; the bottom plate wall thickness of the flow channel body is 1 mm; the material of the flow channel body is aluminum alloy;

[0052] The first spiral flow channel 1 and the second spiral flow channel 2 are both non-uniform width structures; the widest part of the first spiral flow channel 1 and the second spiral flow channel 2 is 29 mm, and the narrowest part is 11 mm; the height of the first spiral flow channel 1 and the second spiral flow channel 2 is 3.5 mm;

[0053] Reinforcement weldments 3 are independently and spaced apart along the center lines of the first spiral flow channel 1 and the second spiral flow channel 2 , and the height of the reinforcement weldments 3 is 3.5 mm.

[0054] The preparation method of the cooling plate comprises the following steps:

[0055] (1) a first spiral flow channel 1 and a second spiral flow channel 2 are opened inside the flow channel body, and then a surface of the flow channel body is pickled for 40 seconds using a hydrofluoric acid solution with a concentration of 12% to obtain a body to be welded;

[0056] (2) The cover plate and the main body to be welded obtained in step (1) are subjected to vacuum diffusion welding. The vacuum diffusion welding temperature is 555° C., the pressure is 1.8 MPa, the time is 2.2 h, and the vacuum degree is 1.8×10 -2 Pa; and then through rough milling and fine milling, the cooling disc body is obtained.

[0057] Example 3

[0058] The present embodiment provides a cooling plate, which comprises a flow channel body and a cover plate matched with the flow channel body; the flow channel body is provided with a first spiral flow channel 1 and a second spiral flow channel 2, the first spiral flow channel 1 and the second spiral flow channel 2 are arranged in a spiral manner, the first ends of the first spiral flow channel 1 and the second spiral flow channel 2 are independent of each other, and the ends are connected to each other; the bottom plate wall thickness of the flow channel body is 1.2 mm; the material of the flow channel body is aluminum alloy;

[0059] The first spiral flow channel 1 and the second spiral flow channel 2 are both non-uniform width structures; the widest part of the first spiral flow channel 1 and the second spiral flow channel 2 is 31 mm, and the narrowest part is 13 mm; the height of the first spiral flow channel 1 and the second spiral flow channel 2 is 4.5 mm;

[0060] Reinforcement weldments 3 are independently and spaced apart along the center lines of the first spiral flow channel 1 and the second spiral flow channel 2 , and the height of the reinforcement weldments 3 is 4.5 mm.

[0061] The preparation method of the cooling plate comprises the following steps:

[0062] (1) a first spiral flow channel 1 and a second spiral flow channel 2 are opened inside the flow channel body, and then a surface of the flow channel body is pickled for 20 seconds using a hydrofluoric acid solution having a concentration of 14% to obtain a body to be welded;

[0063] (2) The cover plate and the main body to be welded obtained in step (1) are subjected to vacuum diffusion welding. The vacuum diffusion welding temperature is 565° C., the pressure is 2.2 MPa, the time is 1.8 h, and the vacuum degree is 0.8×10 -2 Pa; and then through rough milling and fine milling, the cooling disc body is obtained.

[0064] Example 4

[0065] This embodiment provides a cooling plate, which is different from Embodiment 1 in that the first spiral flow channel 1 and the second spiral flow channel 2 are adjusted to have an equal width of 20 mm, and the rest are the same as Embodiment 1.

[0066] Example 5

[0067] This embodiment provides a cooling plate, which is different from the embodiment 1 in that the reinforcing welding parts 3 are not provided in the first spiral flow channel 1 and the second spiral flow channel 2, and the rest is the same as the embodiment 1.

[0068] Example 6

[0069] This embodiment provides a cooling plate body. The difference between the preparation method of the cooling plate body and that of embodiment 1 is that the temperature of the vacuum diffusion welding in step (2) is adjusted to 545° C., and the rest is the same as that of embodiment 1.

[0070] Example 7

[0071] This embodiment provides a cooling plate body. The difference between the preparation method of the cooling plate body and that of embodiment 1 is that the temperature of the vacuum diffusion welding in step (2) is adjusted to 575° C., and the rest is the same as that of embodiment 1.

[0072] Example 8

[0073] This embodiment provides a cooling plate body. The difference between the preparation method of the cooling plate body and that of embodiment 1 is that the pressure of the vacuum diffusion welding in step (2) is adjusted to 1.5 MPa, and the rest is the same as that of embodiment 1.

[0074] Example 9

[0075] This embodiment provides a cooling plate body. The difference between the preparation method of the cooling plate body and that of embodiment 1 is that the pressure of the vacuum diffusion welding in step (2) is adjusted to 2.5 MPa, and the rest is the same as that of embodiment 1.

[0076] Comparative Example 1

[0077] This comparative example provides a cooling plate body, which is different from Example 1 in that the bottom plate wall thickness of the flow channel body is adjusted to 0.8 mm, and the rest is the same as Example 1.

[0078] Comparative Example 2

[0079] This comparative example provides a cooling plate body, which is different from Example 1 in that the bottom plate wall thickness of the flow channel body is adjusted to 1.5 mm, and the rest is the same as Example 1.

[0080] Comparative Example 3

[0081] This comparative example provides a cooling plate body. The difference between the preparation method of the cooling plate body and that of Example 1 is that the vacuum diffusion welding in step (2) is adjusted to stir friction welding, the diameter of the stirring needle is 2 mm, the rotation speed is 1000 r / min, the feed speed is 100 mm / min, and the rest is the same as that of Example 1.

[0082] The cooling plates provided in Examples 1-9 and Comparative Examples 1-3 were subjected to welding bonding rate tests using a C-Scan tester, and the results are shown in Table 1. The time required for the cooling plates provided in Examples 1-9 and Comparative Examples 1-3 to cool a semiconductor wafer at 200°C to 25°C is shown in Table 1.

[0083] Table 1

[0084] Welding bonding rate (%) Cooling time(s) Example 1 98.5 45 Example 2 98.1 48 Example 3 97.8 50 Example 4 97.2 55 Example 5 94.8 47 Example 6 95.2 48 Example 7 97.4 46 Example 8 95.9 49 Example 9 97.5 50 Comparative Example 1 97.8 43 Comparative Example 2 98.1 60 Comparative Example 3 91.2 50

[0085] It can be seen from Table 1 that the cooling disc provided by the present invention can achieve rapid cooling, and at the same time can significantly improve the welding effect between the flow channel body and the cover plate, and reduce the probability of water leakage;

[0086] From the comparison between Example 1 and Example 4, it can be seen that the flow channel is of equal width structure, and the cooling time of the semiconductor wafer is increased; from the comparison between Example 1 and Example 5, it can be seen that the welding effect of the flow channel body and the cover plate is not adversely affected without the provision of a reinforcing welding piece; from the comparison between Example 1 and Examples 6-9, it can be seen that the temperature and pressure of vacuum diffusion welding are too high or too low, which will reduce the welding degree of the flow channel body and the cover plate, thereby increasing the probability of water leakage;

[0087] By comparing Example 1 with Comparative Examples 1 and 2, it can be seen that if the wall thickness of the bottom plate of the flow channel body is too small, the cooling effect is better, but it will significantly increase the process difficulty and cost; if the wall thickness of the bottom plate is too large, the cooling effect of the semiconductor wafer will be significantly reduced; by comparing Example 1 with Comparative Example 3, it can be seen that the welding effect will be reduced by using stir friction welding compared to vacuum diffusion welding.

[0088] In summary, the cooling plate body provided by the present invention has a first spiral flow channel and a second spiral flow channel arranged in a coiled manner at intervals inside the flow channel main body, and can be injected with cooling medium at the same time, thereby achieving rapid cooling and significantly improving the cooling effect; by designing a suitable bottom plate wall thickness, the time required for cooling the wafer is further reduced, and the performance of the cooling plate is enhanced; by strengthening the setting of the welding parts, the welding effect of the flow channel main body and the cover plate can be significantly improved, and the probability of water leakage can be reduced.

[0089] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Those skilled in the art should understand that any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention are within the protection scope and disclosure scope of the present invention.

Claims

1. A cooling plate, characterized in that: The cooling plate comprises a flow channel body and a cover plate matched with the flow channel body; the flow channel body is provided with a first spiral flow channel and a second spiral flow channel, the first spiral flow channel and the second spiral flow channel are arranged in a spiral manner with an interval, the first ends of the first spiral flow channel and the second spiral flow channel are independent of each other, and the ends are connected to each other; The bottom plate wall thickness of the flow channel body is 1-1.2 mm.

2. The cooling plate according to claim 1, characterized in that: The material of the flow channel body includes aluminum alloy.

3. The cooling plate according to claim 1 or 2, characterized in that: The first spiral flow channel and the second spiral flow channel are both structures of non-equal width.

4. The cooling plate according to claim 3, characterized in that: The widest parts of the first spiral flow channel and the second spiral flow channel are both 29-31 mm, and the narrowest parts are both 11-13 mm; Preferably, the height of the first spiral flow channel and the second spiral flow channel are both 3.5-4.5 mm.

5. The cooling plate according to any one of claims 1 to 4, characterized in that: Strengthening welded parts are independently and spaced apart along the center lines of the first spiral flow channel and the second spiral flow channel; Preferably, the height of the reinforcing weldment is 3.5-4.5 mm.

6. A method for preparing a cooling plate according to any one of claims 1 to 5, characterized in that: The preparation method comprises the following steps: (1) a first spiral flow channel and a second spiral flow channel are opened inside the flow channel body, and then the surface of the flow channel body is pickled to obtain a body to be welded; (2) Vacuum diffusion welding is performed on the cover plate and the main body to be welded obtained in step (1), and then post-processed to obtain the cooling plate body.

7. The preparation method according to claim 6, characterized in that: The acid solution used in the pickling treatment in step (1) includes a hydrofluoric acid solution with a concentration of 12-14%; Preferably, the pickling treatment time in step (1) is 20-40s.

8. The preparation method according to claim 6 or 7, characterized in that: The temperature of the vacuum diffusion welding in step (2) is 555-565°C; Preferably, the pressure of the vacuum diffusion welding in step (2) is 1.8-2.2 MPa; Preferably, the vacuum diffusion welding time in step (2) is 1.8-2.2 hours; Preferably, the vacuum degree of the vacuum diffusion welding in step (2) is less than 2×10 -2 Pa.

9. The preparation method according to any one of claims 6 to 8, characterized in that: The post-processing in step (2) includes rough milling and fine milling.

10. The preparation method according to any one of claims 6 to 9, characterized in that: The preparation method comprises the following steps: (1) a first spiral flow channel and a second spiral flow channel are opened inside the flow channel body, and then a hydrofluoric acid solution with a concentration of 12-14% is used to pickle the surface of the flow channel body for 20-40 seconds to obtain a body to be welded; (2) Vacuum diffusion welding is performed on the cover plate and the main body to be welded obtained in step (1), wherein the vacuum diffusion welding temperature is 555-565°C, the pressure is 1.8-2.2 MPa, the time is 1.8-2.2 h, and the vacuum degree is less than 2×10 -2 Pa; and then through rough milling and fine milling, the cooling disc body is obtained.

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