Cleaning equipment for reducing wafer surface metal residue and application on 12-inch wafer

Abstract

The application provides a cleaning device for reducing metal residues on a wafer surface and its application on a 12-inch wafer, which comprises a cleaning tank and a transfer device for transferring a built-in wafer cassette, wherein the transfer device comprises a first bearing body, a second bearing body is rotationally connected to the inner wall of the first bearing body, the wafer cassette is arranged on the surface of the second bearing body, a limiting bearing device is installed on the outer side of the second bearing body, the limiting bearing device comprises two bearing rods, the bearing rods extend along the length direction of the wafer cassette, the limiting bearing device further comprises a first adjusting assembly for controlling the spacing between the two bearing rods and a second adjusting assembly for controlling the spacing between the two bearing rods and the wafer cassette. The application can adapt to wafers of different sizes, and improves the efficiency and quality of batch cleaning of wafers.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of wafer cleaning, in particular to a cleaning device for reducing metal residues on the surface of a wafer and its application on a 12-inch wafer. BACKGROUND

[0002] The surface of a regenerated wafer mostly contains a large amount of metal impurities, and the regenerated wafer needs to be deeply processed and cleaned during the recycling process to remove the metal residues on the surface of the wafer and ensure the normal production and processing of the wafer.

[0003] The regenerated wafer is mostly batch cleaned, and during the cleaning process, multiple wafers are placed in a cassette, the cassette and the wafers are soaked in a cleaning liquid for chemical cleaning or ultrasonic cleaning. In the conventional cleaning device, the wafer and the cassette are in a relatively static state at the predetermined position during the cleaning process, and the bottom of the wafer is constantly in a bearing state and tightly abuts against the inner wall of the cassette, which has a dead corner that is difficult to clean deeply.

[0004] Controlling the overturning of the cassette and the wafer during the cleaning process and supporting the wafer at the bottom can change the cleaning position of the wafer, achieve deep cleaning of the surface of the wafer, and improve the cleaning quality of the wafer surface. However, for wafers of different sizes, different size supporting structures need to be adapted to ensure the stability of the wafer in the supporting state after overturning. Replacing different size supporting structures can solve the above problems, but multiple supporting structures need to be matched, and manual replacement of the supporting structure is required during the cross cleaning process of wafers of different sizes, which affects the efficiency of the regenerated wafer cleaning. At the same time, frequent replacement of the disassembled structure affects the service life of the connection of the supporting structure and the stability of the wafer placement. SUMMARY

[0005] To solve the above problems, the present application provides a cleaning device for reducing metal residues on the surface of a wafer and its application on a 12-inch wafer, which can adapt to wafers of different sizes, improving the efficiency and quality of batch cleaning of wafers.

[0006] To solve the above problems, the technical solution adopted by the present application is:

[0007] The application discloses a cleaning equipment for reducing wafer surface metal residues, which comprises a cleaning tank and a transfer device for transferring an inner wafer box, wherein the transfer device comprises a first bearing main body, a second bearing main body rotatably connected to the inner wall of the first bearing main body, the wafer box arranged on the surface of the second bearing main body, a limiting bearing device mounted on the outer side of the second bearing main body, the limiting bearing device comprising two bearing rods extending along the length direction of the wafer box, a first adjusting assembly for controlling the distance between the two bearing rods and a second adjusting assembly for controlling the distance between the two bearing rods and the wafer box, and the distance between the two bearing rods is adjusted according to the size of the wafer to limit and bear the top of the wafer.

[0008] Preferably, the second bearing main body is provided with a second rotary joint on the side wall, and the deflection angle of the two bearing rods is adjusted through the second rotary joint.

[0009] Preferably, the surface of the bearing rod is sleeved with a flexible limiting sleeve, and the flexible limiting sleeve is filled with a bearing limiting medium.

[0010] Preferably, the bearing limiting medium is an electrorheological fluid, and the flexible limiting sleeve is provided with an electrically conductive assembly.

[0011] Preferably, a hydraulic cleaning device is arranged below the second bearing main body, and the hydraulic cleaning device is controlled to extend into the bottom of the wafer box to limit and clean the wafer and the inner wall of the wafer box.

[0012] Preferably, the hydraulic cleaning device comprises a cleaning bearing plate, the upper end of the cleaning bearing plate is fixed with a hydraulic cleaning assembly matched with the wafer box, and a third adjusting assembly is arranged between the cleaning bearing plate and the second bearing main body.

[0013] Preferably, a first positioning assembly is arranged between the two bearing rods, and the first positioning assembly is electrically connected with the first adjusting assembly for adjusting the distance between the two bearing rods.

[0014] Preferably, a second positioning assembly is arranged between the bearing rod and the second bearing main body, and the second positioning assembly is electrically connected with the second adjusting assembly for adjusting the distance between the bearing rod and the second bearing main body.

[0015] Preferably, the first bearing main body and the second bearing main body are both hollow frame structures, the first bearing main body comprises a peripheral rectangular frame, the rectangular frame is rotatably connected with the second bearing main body through a driving rotating shaft, and an electric control assembly for controlling the rotation of the driving rotating shaft is fixed on the outer wall of the rectangular frame.

[0016] The application of the cleaning equipment for reducing metal residue on wafer surfaces on 12-inch wafers includes the following steps: S1, fixing the wafer cassette containing the 12-inch wafer to the upper surface of the second support body; S2, adjusting the distance between the two support rods according to the size of the 12-inch wafer, and then controlling the two support rods to descend and press against the upper end of the 12-inch wafer to complete one cleaning; S3, after a predetermined cleaning time, controlling the second support body and the wafer cassette to rotate synchronously to complete a second cleaning, and adjusting the second adjustment component to extend a predetermined length during the second cleaning process.

[0017] The beneficial effects of this invention are as follows:

[0018] The above structural design enables adaptive support for wafers of different sizes, ensuring the stability of the wafers during the flipping and cleaning process. At the same time, the overall structural adjustment process does not require personnel to replace the limiting support device. The overall adjustment operation is carried out automatically without the need to disassemble or replace the internal structure, which improves the stability, adaptability and efficiency of the wafer cleaning process. Attached Figure Description

[0019] Figure 1 This is a three-dimensional structural diagram of the present invention.

[0020] Figure 2 This is a three-dimensional structural diagram of the transfer device of the present invention.

[0021] Figure 3 For the present invention Figure 2 A schematic diagram of the main structure.

[0022] Figure 4 For the present invention Figure 2 A top-view structural diagram.

[0023] Figure 5 For the present invention Figure 5 A schematic diagram of the AA-direction cross-section structure.

[0024] Figure 6 For the present invention Figure 5 A magnified structural diagram at point C.

[0025] Figure 7 For the present invention Figure 5 Schematic diagram of the BB-direction cross-section structure.

[0026] Figure 8 This is a three-dimensional structural diagram of the cassette of the present invention.

[0027] Figure 9 This is a schematic diagram of the cleaning steps of the present invention.

[0028] In the diagram: 100, cleaning tank; 200, wafer; 300, wafer cassette; 310, receiving tank; 400, first supporting body; 410, rectangular frame; 420, electrical control assembly; 421, drive shaft; 430, connector; 500, second supporting body; 600, limiting supporting device; 610, flexible limiting sleeve; 620, supporting rod; 630, first adjusting assembly; 640, second adjusting assembly; 650, second rotary joint; 700, hydraulic cleaning device; 710, cleaning support plate; 720, hydraulic cleaning assembly; 721, mounting bracket; 722, cleaning end; 730, third adjusting assembly. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0030] Regenerated wafer technology can reuse waste wafers, reducing environmental pollution and production costs.

[0031] Regenerated wafers often contain a large number of metal impurities on their surface. Deep cleaning is required during the recycling process to remove metal residues from the wafer surface and ensure the normal operation of subsequent wafer production.

[0032] Most regenerated wafers are cleaned in batches. During the cleaning process, multiple wafers are placed in a wafer cassette, and the cassette and wafers are immersed in a cleaning liquid for chemical or ultrasonic cleaning. In traditional cleaning equipment, the wafers and wafer cassettes are in a relatively static state in a predetermined position during the cleaning process. The bottom of the wafer is constantly under load and pressed against the inner wall of the wafer cassette, resulting in dead corners that are difficult to clean deeply.

[0033] Controlling the wafer cassette and wafer flipping during the cleaning process, and supporting the wafer at the bottom, can change the wafer cleaning position, achieving deep cleaning of the wafer surface and improving the quality of wafer surface cleaning. However, for wafers of different sizes, different sizes of bottom support structures are required to ensure the stability of the support state after the wafer is flipped. The above problems can be solved by changing the support structure of different sizes, but multiple support structures are required. Furthermore, during the cross-cleaning of wafers of different sizes and batches, the support structure needs to be replaced manually, which affects the efficiency of regenerated wafer cleaning. At the same time, frequent replacement of the disassembly and assembly structure affects the lifespan of the support structure connection and the stability of wafer placement.

[0034] To solve the above problems, please refer to the appendix. Figure 1 -Appendix Figure 9The cleaning equipment for reducing metal residue on the wafer surface includes a cleaning tank 100 and a transfer device for transferring the wafer cassette 300 containing the wafers 200. The transfer device transfers the wafer cassette 300 and the wafers 200 inside the wafer cassette 300 to the cleaning tank 100 for continuous cleaning to remove residual metal impurities on the surface of the wafers 200.

[0035] Specifically, the transfer device includes a first carrier body 400, a second carrier body 500 rotatably connected to the inner wall of the first carrier body 400, a wafer cassette 300 disposed on the surface of the second carrier body 500, and a limiting carrier device 600 installed on the outer side of the second carrier body 500. After the wafer cassette 300 and the wafers 200 are cleaned in the first state for a predetermined time, the limiting carrier device 600 is controlled to press the wafers 200 in the wafer cassette 300 together from above. After pressing is completed, the overall structure of the wafer cassette 300, the wafers 200, and the second carrier body 500 is controlled to rotate 180° so that the wafers 200 are in the opposite second state. At this time, the opening of the wafer cassette 300 is facing downward, and multiple wafers 200 tend to move downward under the action of gravity. By setting the limiting carrier device 600, the wafers 200 can be pressed together, preventing the overall structure from shifting during the rotation process.

[0036] After the flipping and cleaning, the limiting support device 600 can be controlled to move down as a whole, changing the relative position of the wafer 200 in the wafer cassette 300. This exposes the cleaning dead corners of the wafer 200 and the wafer cassette 300 to the outside, thereby achieving efficient cleaning of the surface of the wafer 200.

[0037] To provide adaptive support for wafers 200 of different sizes and ensure their stability during the flipping and cleaning process, the limiting support device 600 includes two support rods 620 extending along the length of the wafer cassette 300. The limiting support device 600 also includes a first adjusting component 630 controlling the distance between the two support rods 620 and a second adjusting component 640 controlling the distance between the two support rods 620 and the wafer cassette 300. The distance between the two support rods 620 is adjusted according to the size of the wafer 200 to limit the support of the top of the wafer 200. When the wafer 200 is large, the distance between the two support rods 620 is increased; conversely, when the wafer 200 is small, the distance between the two support rods 620 is decreased, thus providing adaptive adjustment for wafers 200 of different sizes.

[0038] Through the above structural design, it is possible to provide adaptive support for wafers 200 of different sizes, ensuring the stability of wafers 200 during the flipping and cleaning process; at the same time, the limit support device 600 does not need to be replaced by staff during the overall structural adjustment process, and the overall adjustment operation is carried out automatically without the need to disassemble and replace the internal structure, which improves the stability, adaptability and efficiency of wafers 200 during the cleaning process.

[0039] It should also be noted that by setting the second adjustment component 640, the height position of the two support rods 620 can be adjusted, allowing the two support rods 620 to move closer to or further away from the wafer 200. During the loading and unloading process of the wafer cassette 300 and the wafer 200, the support rods 620 can be controlled to extend to their limit position, allowing the wafer cassette 300 to be replaced smoothly, further improving the overall cleaning efficiency.

[0040] The second support body 500 has a second rotating joint 650 installed on its side wall. The second rotating joint 650 adjusts the deflection angle of the two support rods 620. During the loading and unloading of wafers 200 and wafer cassettes 300, the second rotating joint 650 controls the support rods 620 to deflect to the outside, which can further offset the wafers 200 and wafer cassettes 300 by a larger area, making it easier to load and unload wafers 200 and wafer cassettes 300. At the same time, it can meet the requirements of disassembling and replacing wafer cassettes 300 and wafers 200 of different sizes.

[0041] A flexible limiting sleeve 610 is fitted on the surface of the support rod 620. The flexible limiting sleeve 610 is filled with a support limiting medium. By setting the support limiting medium, the wafer 200 can be supported and limited to fit together, so that multiple wafers 200 can be in a more stable state during the flipping and cleaning process. At the same time, it can prevent the support rod 620 from directly and rigidly contacting the wafer 200, thus avoiding damage to the surface of the wafer 200.

[0042] The preferred bearing and limiting medium is electrorheological fluid. The flexible limiting sleeve 610 has a built-in conductive component, which can change the state of the electrorheological fluid. In the initial state, the electrorheological fluid is controlled to be in a non-conductive flexible state. At this time, the bearing and limiting medium can deform under the pressure. The container holding the electrorheological fluid can adapt to the deformation and provide adaptive support for the wafer 200. During the flipping and cleaning stage, the electrorheological fluid is controlled to be in a rigid state. At this time, the electrorheological fluid can provide stable support for the wafer 200 and prevent the overall structure of the bearing rod 620 from shaking during the up and down movement. This ensures the stability of the wafer 200 during the cleaning process and ensures the cleaning effect on the surface of the wafer 200.

[0043] In summary, by setting the bearing and limiting medium as electrorheological fluid, multiple wafers 200 can be adaptively supported. The rigidity and flexibility of the electrorheological fluid can be adjusted according to the cleaning state of the wafers 200, thus meeting the requirements of adaptive cleaning. Compared with traditional simply flexible limiting materials, this limiting and bearing method is more suitable for flipping and cleaning the wafers 200, ensuring the stability of the support and deep cleaning.

[0044] A hydraulic cleaning device 700 is installed below the second support body 500. The hydraulic cleaning device 700 is controlled to extend into the bottom of the wafer cassette 300 to limit the wafer 200 and clean the inner wall of the wafer cassette 300. The hydraulic cleaning device 700 can support and limit the wafer 200 from the second side, further ensuring the stability of the wafer 200 in the flipping cleaning state. At the same time, the surface of the hydraulic cleaning device 700 can spray cleaning medium to impact the surface of the wafer 200 from the second side, deeply cleaning the areas of the wafer 200 that are difficult to clean, further improving the overall cleaning effect of the wafer 200 and improving the quality of the finished wafer 200.

[0045] Specifically, the hydraulic cleaning device 700 includes a cleaning support plate 710, with a hydraulic cleaning component 720 adapted to the wafer cassette 300 fixed at the upper end of the cleaning support plate 710. A third adjustment component 730 is installed between the cleaning support plate 710 and the second support body 500. The distance between the cleaning support plate 710 and the second support body 500 can be adjusted through the third adjustment component 730, thereby adjusting the distance between the hydraulic cleaning component 720 and the wafer 200, so as to achieve tight contact with the wafer 200. At the same time, the hydraulic cleaning component 720 extends into the second side of the wafer 200 to achieve deep cleaning of the dead corner area of ​​the wafer 200. The outward protrusion design of the hydraulic cleaning component 720 can be adapted to the bottom of the wafer cassette 300 and can extend into the wafer cassette 300 to clean the wafer 200.

[0046] It should be noted that the wafer cassette 300 has an opening design on both the top and bottom sides. Multiple receiving slots 310 are formed on the inner wall of the wafer cassette 300. The width of the receiving slots 310 is slightly larger than the thickness of the wafer 200, so that the wafer 200 can smoothly enter the receiving slots 310 for positioning. At the same time, after the wafer 200 is flipped down, the wafer 200 can swing left and right a predetermined distance within the receiving slots 310, which further improves the cleaning effect of the contact area between the wafer 200 and the wafer cassette 300 and further avoids the residue of metal impurities.

[0047] All of the above-mentioned adjustment components can be selected as electric telescopic rod structures, and the telescopic length can be precisely controlled by electric structure to meet the cleaning and processing requirements of wafers of different sizes.

[0048] A first positioning component is installed between the two support rods 620. The first positioning component is electrically connected to the first adjustment component 630 to adjust the distance between the two support rods 620. The distance between the two support rods 620 is adjusted according to the size of the wafer 200. The first positioning component is used for calibration and testing to ensure the accuracy of the electric adjustment and testing process.

[0049] A second positioning component is installed between the support rod 620 and the second support body 500. The second positioning component is electrically connected to the second adjustment component 640 to adjust the distance between the support rod 620 and the second support body 500. Similarly, the distance between the support rod 620 and the second support body 500 is adjusted according to the size of the wafer 200 to control the rise and fall of the support rod 620 to a predetermined height, thereby completing the adaptive clamping and support of the wafer 200 and meeting the adaptive cleaning requirements of different types of wafers 200.

[0050] Both the first support body 400 and the second support body 500 are hollow frame structures. The first support body 400 includes an outer rectangular frame 410. The rectangular frame 410 and the second support body 500 are rotatably connected by a drive shaft 421. An electronic control component 420 for controlling the rotation of the drive shaft 421 is fixed on the outer wall of the rectangular frame 410. The electronic control component 420 can control the second support body 500 to rotate 180°. The hollow area formed by the outer rectangular frame 410 is relatively large, allowing the second support body 500 and the wafer cassette 300 on the surface of the second support body 500 to rotate and pass through. A connector 430 is also fixed on the surface of the outer rectangular frame 410. The connector 430 can be connected to an electric robotic arm to control the overall structure to enter and exit the cleaning tank 100 to achieve deep cleaning of multiple wafers 200.

[0051] Please refer to the appendix for details. Figure 9 The application of cleaning equipment for reducing metal residue on wafer surfaces on 12-inch wafers includes the following steps:

[0052] S1. Fix the wafer cassette 300 containing 12-inch wafers to the upper surface of the second support body 500; the wafer cassette 300 and the second support body 500 are detachably connected and can be fixed by an electric retraction structure or a manual bolt structure; multiple wafer cassettes 300 can be fixed along the length of the second support body 500.

[0053] S2. Adjust the distance between the two support rods 620 according to the size of the 12-inch wafer, and then control the two support rods 620 to descend and press against the top of the 12-inch wafer to complete one cleaning cycle; adjust the distance between the two support rods 620 to match the 12-inch wafer. After the distance between the two support rods 620 is adjusted, control the two support rods 620 to move towards the wafer 200 and press against the surface of the wafer 200 to ensure the stability of multiple wafers 200 during the flipping process.

[0054] S3. After a predetermined cleaning time, the second carrier body 500 and the wafer cassette 300 are controlled to rotate synchronously to complete the second cleaning. During the second cleaning process, the second adjustment component 640 is adjusted to extend downward by a predetermined length. During the predetermined second cleaning time, the wafer 200 is controlled to descend a predetermined distance relative to the wafer cassette 300. At this time, the wafers 200 are staggered, exposing the cleaning dead corner between the wafer 200 and the wafer cassette 300 to the outside, thereby achieving deep and efficient cleaning of the surface of the wafer 200.

[0055] Through the above structural design, it is possible to make adaptive adjustments to wafers 200 of different sizes, thereby improving the efficiency and quality of batch cleaning of wafers 200.

[0056] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A cleaning apparatus for reducing metal residue on wafer surfaces, comprising a cleaning tank (100) and a transfer device for transferring a wafer cassette (300) containing wafers (200), characterized in that: The transfer device includes a first carrier body (400), and a second carrier body (500) is rotatably connected to the inner wall of the first carrier body (400). The wafer cassette (300) is disposed on the surface of the second carrier body (500). A limiting carrier device (600) is installed on the outer side of the second carrier body (500). The limiting carrier device (600) includes two carrier rods (620). The carrier rods (620) extend along the length direction of the wafer cassette (300). The limiting carrier device (600) also includes a first adjusting component (630) for controlling the distance between the two carrier rods (620) and a second adjusting component (640) for controlling the distance between the two carrier rods (620) and the wafer cassette (300). The distance between the two carrier rods (620) is adjusted according to the size of the wafer (200) to complete the bearing and limiting of the top of the wafer (200). A hydraulic cleaning device (700) is provided below the second carrier body (500). The hydraulic cleaning device (700) is controlled to extend into the bottom of the wafer cassette (300) to limit the wafer (200) and clean the inner wall of the wafer cassette (300). The hydraulic cleaning device (700) includes a cleaning support plate (710), and a hydraulic cleaning component (720) adapted to the cassette (300) is fixed at the upper end of the cleaning support plate (710). A third adjustment component (730) is installed between the cleaning support plate (710) and the second support body (500).

2. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 1, characterized in that, The second bearing body (500) has a second rotary joint (650) installed on its side wall, through which the deflection angle of the two bearing rods (620) is adjusted.

3. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 1, characterized in that, The surface of the bearing rod (620) is fitted with a flexible limiting sleeve (610), and the flexible limiting sleeve (610) is filled with a bearing limiting medium.

4. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 3, characterized in that, The bearing limiting medium is an electrorheological fluid, and the flexible limiting sleeve (610) has a built-in conductive component.

5. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 1, characterized in that, A first positioning component is installed between the two support rods (620), and the first positioning component is electrically connected to the first adjustment component (630) for adjusting the distance between the two support rods (620).

6. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 1, characterized in that, A second positioning component is installed between the bearing rod (620) and the second bearing body (500). The second positioning component is electrically connected to the second adjustment component (640) to adjust the distance between the bearing rod (620) and the second bearing body (500).

7. The cleaning equipment for reducing metal residue on wafer surfaces according to claim 1, characterized in that, The first supporting body (400) and the second supporting body (500) are both hollow frame structures. The first supporting body (400) includes an outer rectangular frame (410). The rectangular frame (410) and the second supporting body (500) are rotatably connected by a drive shaft (421). An electronic control component (420) for controlling the rotation of the drive shaft (421) is fixed on the outer wall of the rectangular frame (410).

8. The application of cleaning equipment for reducing metal residue on wafer surfaces on 12-inch wafers, characterized in that, The cleaning apparatus for reducing metal residue on wafer surfaces according to any one of claims 1-7 includes the following steps: S1. Fix the wafer cassette (300) containing the 12-inch wafer to the upper surface of the second support body (500); S2. Adjust the distance between the two support rods (620) according to the size of the 12-inch wafer, and then control the two support rods (620) to descend and press against the top of the 12-inch wafer to complete one cleaning cycle; S3. After a predetermined cleaning time, control the second carrier body (500) and the film box (300) to rotate synchronously to complete the second cleaning. During the second cleaning process, adjust the second adjustment component (640) to extend downwards by a predetermined length.

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