Wafer back cleaning device

Abstract

The embodiment of the utility model discloses a wafer back cleaning device which comprises a vacuum chuck, a first air channel assembly and a second air channel assembly. The vacuum chuck is provided with an inner groove and an outer groove, and the outer groove is located on the periphery of the inner groove. Wherein the first air channel assembly is communicated with the inner groove; the second air channel assembly is communicated with the outer groove. By implementing the device provided by the embodiment of the utility model, the cleaning liquid cannot be adsorbed on the suction cup due to the negative pressure of the vacuum suction cup in the cleaning process of the back surface of the wafer, so that the problem that the liquid is remained on the back surface of the wafer is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of semiconductor manufacturing, in particular to a wafer backside cleaning device. Background Art

[0002] During the wafer cleaning process, the front side of the wafer is mainly cleaned. However, as the feature size of semiconductors becomes smaller and smaller, the requirements for the cleanliness of the back side of the wafer are getting higher and higher. Therefore, when cleaning a wafer, a single wafer cleaning device usually cleans both the front and back sides of the wafer at the same time.

[0003] In the backside cleaning of semiconductor wafers, vacuum chucks are used to fix the wafers to ensure stable rotation. However, due to the possible errors in the processing accuracy of the vacuum chucks, their surface flatness may not be perfect. This uneven flatness results in uneven adsorption force when vacuum adsorption is applied to the wafer, which may cause vacuum leakage. Therefore, if Figure 1 and Figure 2 As shown, negative pressure zones are formed at the edge of the vacuum chuck, and the cleaning liquid will be adsorbed into these negative pressure zones during the rotation process. This increases the possibility of the cleaning liquid remaining on the back of the wafer, thereby affecting the final cleaning effect and causing residues or contamination on the wafer surface, affecting the quality of semiconductor devices.

[0004] Therefore, it is necessary to design a new device to ensure that during the cleaning process of the back of the wafer, the cleaning liquid will not be adsorbed onto the suction cup due to the negative pressure of the vacuum suction cup, thereby avoiding the problem of liquid residue on the back of the wafer. Utility Model Content

[0005] The purpose of the utility model is to overcome the defects of the prior art and provide a wafer backside cleaning device.

[0006] In order to solve the above technical problems, the purpose of the present invention is achieved through the following technical solutions: providing a wafer backside cleaning device, comprising: a vacuum suction cup, a first air channel assembly and a second air channel assembly; the vacuum suction cup is provided with an inner groove and an outer groove, the outer groove is located on the outer periphery of the inner groove;

[0007] wherein, the first airway component is in communication with the inner tank;

[0008] The second air passage assembly is in communication with the outer tank.

[0009] A further technical solution is: it also includes a rotating component, and the vacuum suction cup is connected above the rotating component.

[0010] Its further technical solution is: the rotating assembly includes a rotating shaft, a coupling, a bearing and a power source, wherein one end of the rotating shaft is connected to the vacuum suction cup; the other end of the rotating shaft is connected to the coupling, and the coupling is connected to the power source.

[0011] A further technical solution is: it also includes a plurality of outer sealing rings, wherein the plurality of outer sealing rings are located between the rotating assembly and the vacuum suction cup; and the plurality of outer sealing rings are located below the outer groove.

[0012] A further technical solution is: the outer sealing ring includes a CDA sealing ring.

[0013] A further technical solution is: it also includes an inner sealing ring, which is located between the rotating component and the vacuum suction cup; and a plurality of the inner sealing rings are located below the inner groove.

[0014] A further technical solution is: the inner sealing ring includes a VAC sealing ring.

[0015] A further technical solution is: the first airway component includes a VAC airway system.

[0016] A further technical solution is: the second airway component includes a CDA airway system.

[0017] A further technical solution is as follows: the vacuum suction cup is further provided with a plurality of liquid leakage ports, and the plurality of liquid leakage ports are arranged in the outer groove.

[0018] A further technical solution is: it also includes a drainage component, which is connected to the leakage port to detect whether the outer tank leaks and drain the liquid when the outer tank leaks.

[0019] A further technical solution is that the side surface of the liquid leakage port is arranged to be inclined relative to the vertical plane.

[0020] A further technical solution is that the inclination angle of the side surface of the leakage port relative to the vertical plane is less than 120°.

[0021] The beneficial effects of the present invention compared to the prior art are as follows: the present invention is provided with an inner groove and an outer groove through a vacuum suction cup, the inner groove is evacuated by the first air duct assembly to fix the wafer, and the outer groove is filled with gas by the second air duct assembly to maintain positive pressure. It is also equipped with a rotating assembly and sealing rings located under the inner groove and the outer groove respectively. The first air duct assembly uses a VAC air duct system, and the second air duct assembly uses a CDA air duct system. During the cleaning process of the back of the wafer, the cleaning liquid will not be adsorbed onto the suction cup due to the negative pressure of the vacuum suction cup, thereby avoiding the problem of liquid residue on the back of the wafer. In addition, multiple leakage ports and drainage components are provided to effectively detect and deal with leakage problems. The inclined design of the leakage port helps to improve the flow efficiency of the cleaning liquid and avoid the accumulation of cleaning liquid.

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0024] Figure 1 A schematic diagram of vacuuming a vacuum suction cup in the prior art;

[0025] Figure 2 A schematic diagram of a negative pressure area of ​​a vacuum suction cup in the prior art;

[0026] Figure 3 A schematic diagram of the three-dimensional structure of a wafer backside cleaning device provided by an embodiment of the present invention;

[0027] Figure 4 A schematic cross-sectional view of a wafer backside cleaning device provided by an embodiment of the present invention;

[0028] Figure 5 A schematic top view of a wafer backside cleaning device provided by an embodiment of the present invention;

[0029] Figure 6 A schematic diagram illustrating the working principle of a wafer backside cleaning device provided by an embodiment of the present invention;

[0030] Figure 7 A schematic diagram of a negative pressure area of ​​a wafer backside cleaning device provided by an embodiment of the present invention;

[0031] Figure 8 A schematic diagram of the three-dimensional structure of a wafer backside cleaning device provided by another embodiment of the present invention;

[0032] Figure 9 A schematic cross-sectional view of a wafer backside cleaning device provided by another embodiment of the present invention;

[0033] Figure 10 A schematic top view of a wafer backside cleaning device provided by another embodiment of the present invention;

[0034] Figure 11 A schematic cross-sectional view of a vacuum suction cup according to another embodiment of the present invention;

[0035] Figure 12 A schematic diagram showing the connection between the liquid leakage port and the liquid discharge assembly provided in another embodiment of the present invention;

[0036] Description of the symbols in the figure:

[0037] 10. Vacuum suction cup; 11. Inner groove; 12. Outer groove; 20. Rotating shaft; 21. Power source; 22. Coupling; 23. Bearing; 30. Outer sealing ring; 40. Inner sealing ring; 50. VAC airway pipe; 60. CDA airway pipe; 70. Sealing ring; 80. Leakage port; 90. Leakage sensor; 100. Back suction valve; 110. Wafer. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0039] It will be understood that when used in this specification and the appended claims, the terms “comprises” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or groups thereof.

[0040] It should also be understood that the terms used in this utility model specification are only for the purpose of describing specific embodiments and are not intended to limit the utility model. As used in this utility model specification and the appended claims, the singular forms "a", "an" and "the" are intended to include plural forms unless the context clearly indicates otherwise.

[0041] It should be further understood that the term “and / or” used in the present specification and the appended claims refers to any and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0042] like Figure 1 and Figure 2 As shown, there may be errors in the processing accuracy of the vacuum suction cup 10 in the existing wafer back side cleaning device, and its surface flatness is not perfect, which will lead to uneven adsorption force, thereby causing vacuum leakage. A negative pressure zone is formed in the edge area of ​​the vacuum suction cup 10, and the cleaning liquid will be adsorbed into these negative pressure areas during the rotation process, which increases the possibility of the cleaning liquid remaining on the back side of the wafer 110, thereby affecting the cleaning effect, and may cause residues or contamination on the surface of the wafer 110, thereby affecting the quality of the semiconductor device.

[0043] To this end, the present invention provides a wafer backside cleaning device. By providing an inner groove 11 and an outer groove 12 on a vacuum chuck 10, a first air duct assembly evacuates the inner groove 11 area, firmly securing the wafer 110 on the vacuum chuck 10. Simultaneously, a second air duct assembly fills the outer groove 12 with gas to maintain a positive pressure. This positive pressure prevents the cleaning liquid from being sucked onto the vacuum chuck 10 by the negative pressure, thereby preventing liquid from remaining on the backside of the wafer 110.

[0044] In addition, due to the existence of positive pressure, theoretically the cleaning liquid will not enter the positive pressure area, but there will be special circumstances, such as when the positive pressure suddenly disappears, or when the positive pressure is lower than the debugged pressure value, when the cleaning liquid leaks, the liquid will preferentially enter the positive pressure area formed by the outer tank 12, and enter the drainage structure along the leakage port 80, so that the leakage problem can be solved in time.

[0045] Therefore, in order to solve the problem that the cleaning liquid is adsorbed into these negative pressure areas during the rotation process, the present invention adopts two different technical solutions to solve the above problem. The two solutions are as follows:

[0046] The first solution is to secure wafer 110 to the backside of the wafer cleaning device using a vacuum suction cup 10. The inner chamber 11 is evacuated via a first airway assembly, holding wafer 110 against the suction cup. The outer chamber 12 is filled with gas via a second airway assembly to maintain positive pressure and prevent liquid adsorption. The device is equipped with a rotating assembly to rotate wafer 110 during the cleaning process, improving cleaning efficiency. The outer and inner sealing rings 30 and 40 ensure that the cleaning liquid does not leak, maintaining the sealing performance of each component. The first airway assembly uses a VAC system for vacuuming, while the second airway assembly uses a CDA system for gas supply. Ultimately, this design effectively prevents cleaning liquid from remaining on the backside of wafer 110.

[0047] The second solution is to add a structure for draining liquid based on the first solution. Specifically, a leakage port 80 is provided on the vacuum suction cup 10 so that when leakage occurs in the outer groove 12, the liquid can be discharged through the leakage port 80. The drainage component is connected to the leakage port 80 to detect and drain the leakage. The inclination design and angle of the leakage port 80 are specially limited, which helps to effectively collect and drain the liquid.

[0048] The difference between the two solutions is that the first solution focuses on preventing leakage through the airway system and sealing measures, while the second solution adds a special leakage handling function on this basis.

[0049] In order to better understand the above technical solution, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0050] See also Figures 3 to 5 A wafer backside cleaning device includes: a vacuum chuck 10, a first airway assembly, and a second airway assembly; the vacuum chuck 10 is provided with an inner groove 11 and an outer groove 12, and the outer groove 12 is located on the outer periphery of the inner groove 11;

[0051] The first air channel assembly is in communication with the inner groove 11, so as to evacuate the space enclosed by the inner groove 11 and the wafer 110 when the wafer 110 is placed on the vacuum chuck 10, thereby fixing the wafer 110 on the vacuum chuck 10;

[0052] The second air channel assembly is in communication with the outer groove 12 , so as to fill the space enclosed by the outer groove 12 and the wafer 110 with gas to maintain a positive pressure when the wafer 110 is placed on the vacuum chuck 10 .

[0053] Specifically, the inner groove 11 is located in the central area of ​​the vacuum suction cup 10, and the outer groove 12 is located around the inner groove 11; the inner groove 11 and the outer groove 12 are used to fix the wafer 110 on the vacuum suction cup 10 and provide stable support during the cleaning process.

[0054] When the wafer 110 is placed on the vacuum chuck 10, the space enclosed by the inner tank 11 and the wafer 110 is evacuated via the first air channel assembly. This process extracts air from the inner tank 11, creating a negative pressure environment that allows the wafer 110 to fit tightly against the vacuum chuck 10, thereby ensuring the stability and positioning accuracy of the wafer 110 during the cleaning process.

[0055] When the wafer 110 is placed on the vacuum chuck 10, gas is introduced into the space enclosed by the outer tank 12 and the wafer 110 through the second gas channel assembly. This operation maintains a positive pressure in the outer tank 12 area, preventing the liquid in the outer tank 12 from being sucked into the negative pressure area and thus preventing the liquid from entering the negative pressure area, thereby effectively reducing the possibility of liquid residue.

[0056] The working principle of the above-mentioned wafer backside cleaning device is as follows Figure 6 As shown, the vacuum function of the first air channel component can firmly fix the wafer 110 on the vacuum chuck 10, avoiding the movement or displacement of the wafer 110 during the cleaning process, thereby improving the consistency and accuracy of cleaning; the positive pressure of the outer tank 12 is maintained by the second air channel component, which can effectively prevent the cleaning liquid from being adsorbed into the negative pressure area. Figure 7 As shown, liquid does not enter the negative pressure area, reducing the risk of cleaning liquid residue on the back of wafer 110 and improving the cleaning effect. The design of firmly fixing wafer 110 and preventing liquid adsorption ensures a more efficient cleaning process and reduces secondary contamination or incomplete cleaning caused by liquid residue.

[0057] In this example, see Figure 3 and Figure 4 The above-mentioned wafer back side cleaning device also includes a rotating component, and the vacuum suction cup 10 is connected above the rotating component.

[0058] During the cleaning process, the rotating assembly rotates the vacuum chuck 10 and the wafer 110 thereon, allowing the cleaning liquid to evenly cover the entire backside of the wafer 110. During the rotation, the cleaning liquid can better penetrate all areas of the wafer 110, avoiding the problem of insufficient local cleaning that may occur in a stationary state.

[0059] Specifically, in this embodiment, the rotating assembly includes a rotating shaft 20, a coupling 22, a bearing 23, and a power source 21. One end of the rotating shaft 20 is connected to the vacuum suction cup 10; the other end of the rotating shaft 20 is connected to the coupling 22, which is in turn connected to the power source 21. The coupling 22 effectively transmits power, thereby ensuring stable rotation of the rotating shaft 20 and improving uniform coverage and treatment efficiency of the cleaning liquid. Furthermore, the end of the rotating shaft 20 connected to the coupling 22 is connected to the bearing 23, ensuring the axial and radial accuracy of the rotating shaft 20. The stable connection of the rotating shaft 20 and the support of the bearing 23 reduce wear and failure rate of the equipment, thereby extending the service life of the equipment.

[0060] When the rotating assembly is started, the vacuum chuck 10 and the wafer 110 rotate on a horizontal plane. The speed and direction of rotation can be adjusted to meet different cleaning requirements.

[0061] In this example, see Figure 4 The above-mentioned wafer backside cleaning device also includes a plurality of outer sealing rings 30, which are located between the rotating assembly and the vacuum suction cup 10; and the plurality of outer sealing rings 30 are located below the outer groove 12 to ensure that the positive pressure does not leak.

[0062] The outer seals 30 isolate the area between the rotating assembly and the vacuum cup 10, preventing external media (such as air or liquid) from entering or escaping the system. They also prevent positive pressure (i.e., the gas or liquid pressure within the system) from escaping to the external environment; in other words, the outer seals 30 form a sealed barrier to prevent gas or liquid leakage, which is crucial for maintaining the stability and efficiency of the device. The use of the outer seals 30 ensures a stable positive pressure environment, thereby improving the performance and reliability of the device, especially during high-precision cleaning processes.

[0063] In this embodiment, the outer seal ring 30 includes, but is not limited to, a CDA seal ring 70; two of the rings may be provided. CDA seal rings are typically used in applications requiring continuous motion, such as rotational, reciprocating, or vibratory motion, to prevent liquid or gas leakage. CDA seal rings offer excellent wear resistance, chemical resistance, and high-temperature resistance, ensuring effective sealing even under extreme operating conditions.

[0064] Of course, in other embodiments, other numbers of sealing rings 70 may be provided, depending on actual conditions.

[0065] In this example, see Figure 4 The above-mentioned wafer backside cleaning device also includes an inner sealing ring 40, which is located between the rotating assembly and the vacuum suction cup 10; and several inner sealing rings 40 are located below the inner groove 11 to ensure that the vacuum does not leak.

[0066] The primary function of the inner seal 40 is to prevent gases or liquids in the vacuum environment from leaking to the outside. The seal 70 forms a physical barrier, enabling the vacuum environment to remain stable and preventing vacuum pressure loss. This is crucial for the effectiveness and consistency of the backside cleaning process of the wafer 110. By preventing vacuum leaks, the inner seal 40 helps maintain efficient use of the cleaning fluid and system stability, thereby improving the overall efficiency of the wafer 110 cleaning process. Effective sealing reduces system failures caused by leaks, thereby reducing the need for maintenance and repairs, saving cost and time.

[0067] In this embodiment, the inner seal ring 40 includes but is not limited to a VAC seal ring. The VAC seal ring is used as a seal ring 70 in a vacuum environment. They are used to prevent gas or liquid from leaking in the vacuum system to maintain the vacuum level and stability of the system.

[0068] In this example, see Figure 3 and Figure 4 The first airway component includes a VAC airway system; the second airway component includes a CDA airway system.

[0069] A VAC airway system uses vacuum to attract and move gases or particles. In a backside wafer cleaning system, the VAC airway system effectively extracts air or other gases by creating a negative pressure area, allowing the wafer 110 to be attached to the vacuum chuck 10. A CDA airway system uses compressed air to provide air flow. In a backside wafer cleaning system, the CDA airway system provides high-pressure air flow, creating a positive pressure area in the space enclosed by the outer tank 12 and the wafer 110, thereby preventing cleaning liquid from entering the inner tank 11.

[0070] In this embodiment, the VAC airway system includes a vacuum pump and a VAC airway pipe 50; the vacuum pump is connected to the VAC airway pipe 50, which is in communication with the inner tank 11. The CDA airway system includes a compressed air source and a CDA airway pipe 60, which is connected to the CDA airway pipe 60, which is in communication with the outer tank 12. The VAC airway pipe 50 and the CDA airway pipe 60 are built into the rotating shaft 20.

[0071] The combined use of the VAC airway system and the CDA airway system enables more precise gas management, ensuring the system maintains optimal performance under various working conditions.

[0072] In this example, see Figure 4 A plurality of sealing rings 70 are respectively provided at the supply ports of the VAC air duct 50 and the CDA air duct 60 to ensure that the vacuum and positive pressure do not leak when the rotating shaft 20 rotates at high speed.

[0073] In this embodiment, the number of the sealing rings 70 is at least 3. Of course, in other embodiments, the number of the sealing rings 70 can be set according to actual conditions.

[0074] When the wafer backside cleaning device provided in this embodiment is in operation, first, the wafer 110 is placed on the vacuum suction cup 10. The first airway component introduces vacuum into the inner groove 11 of the vacuum suction cup 10 through the VAC airway pipe 50, generating negative pressure, so that the wafer 110 is tightly adsorbed on the vacuum suction cup 10 to prevent movement during the cleaning process. Next, the second airway component introduces positive pressure gas into the outer groove 12 through the CDA airway pipe 60 to form a positive pressure area. This positive pressure area is formed around the wafer 110 to prevent the cleaning liquid from being sucked into the negative pressure area. After the positive and negative pressure values ​​are stable, the power source 21 is started, and the rotating shaft 20 drives the vacuum suction cup 10 to start rotating. At this time, the vacuum suction cup 10 rotates at a speed of 500RPM; the cleaning liquid is sprayed on the back of the wafer 110. Due to the existence of the positive pressure area, the cleaning liquid will not be absorbed into the negative pressure area, so the cleaning liquid will only flow on the back of the wafer 110 and will not be sucked into the interior of the vacuum suction cup 10; after cleaning, no cleaning liquid will remain on the back of the wafer 110, meeting customer requirements.

[0075] Throughout the cleaning process, vacuum chuck 10 effectively secures wafer 110 to the platform, preventing movement or vibration during cleaning and ensuring uniform cleaning. The positive pressure area prevents the cleaning fluid from being drawn into the negative pressure area, preventing liquid contamination within the system and maintaining the cleanliness and stability of the equipment. The combination of rotating wafer 110 and evenly spraying the cleaning fluid ensures the complete removal of the backside cleaning fluid, making the cleaning process efficient and thorough. After cleaning, no residual cleaning fluid remains on the backside of wafer 110, meeting the customer's high standards and ensuring the quality of the final product.

[0076] In addition, the above-mentioned positive and negative pressure values ​​are stable, specifically referring to the negative pressure value of the area formed by the inner groove 11 and the wafer 110 and the negative pressure value of the area formed by the outer groove 12 and the wafer 110 no longer fluctuate. At this time, it can be confirmed that the wafer 110 has been completely adsorbed. In general, the safe negative pressure value of the wafer 110 should be greater than -75kPa. The positive pressure value is adjusted in real time by a proportional valve to ensure that the liquid on the back of the wafer 110 can be effectively blown away. The specific value of the positive pressure value needs to be debugged according to the actual situation to find the optimal setting, because the processing conditions of different devices will be different.

[0077] The wafer backside cleaning device of this embodiment comprises an inner groove 11 and an outer groove 12 provided by a vacuum chuck 10. A first airway assembly evacuates the inner groove 11 to secure the wafer 110, while a second airway assembly fills the outer groove 12 with gas to maintain a positive pressure. The device is also equipped with a rotating assembly and sealing rings 70 positioned below the inner groove 11 and the outer groove 12, respectively. The first airway assembly utilizes a VAC airway system, while the second airway assembly utilizes a CDA airway system. This ensures that during the backside cleaning process of the wafer 110, the cleaning liquid is not attracted to the chuck due to the negative pressure of the vacuum chuck 10, thereby preventing liquid from remaining on the backside of the wafer 110.

[0078] See also Figures 8 to 12 In another embodiment, specifically on the basis of the above embodiment, the vacuum suction cup 10 is further provided with a plurality of liquid leakage ports 80 , and the plurality of liquid leakage ports 80 are arranged in the outer groove 12 .

[0079] The leakage port 80 is used to guide the cleaning liquid to the drainage component in time when leakage occurs in the positive pressure area, to handle the leakage and reduce the accumulation of the cleaning liquid in the outer tank 12.

[0080] It can be seen that the setting of the leakage port 80 helps to drain the liquid more quickly and prevent liquid accumulation from affecting equipment performance; reduce the interference of liquid on the positive pressure area and improve the stability and consistency of the process; once the drainage component detects liquid, the entire device can stop the process in time to prevent potential process risks, and can also quickly drain the cleaning liquid after the process stops to ensure the normal operation and long-term stability of the device.

[0081] In this example, see Figure 12 The above-mentioned wafer backside cleaning device also includes a drain assembly connected to the leakage port 80 to detect whether there is leakage in the outer tank 12 and drain the liquid when leakage occurs in the outer tank 12.

[0082] In this embodiment, the drainage assembly includes a drainage pipe, a leakage sensor 90 and a back-suction valve 100; one end of the drainage pipe is connected to the leakage port 80, the leakage sensor 90 is built into the drainage pipe, and the other end of the drainage pipe is connected to the back-suction valve 100.

[0083] Specifically, during the normal process, due to the existence of positive pressure, the cleaning liquid will theoretically be prevented from entering the area enclosed by the outer tank 12 and the wafer 110. However, if the positive pressure suddenly disappears or falls below the set value, the cleaning liquid may enter the positive pressure area. At this time, the cleaning liquid flows into the drain pipe through the leakage port 80, the leakage sensor 90 will detect the liquid, the device will determine that there is a risk in the process and automatically stop the process. After the process stops, the gas supply to the positive pressure area will stop, and the back suction valve 100 of the drain pipe will quickly open to suck back the cleaning liquid in the positive pressure area and the drain pipe.

[0084] Through rapid detection and response, the system can effectively prevent process interruptions due to liquid problems; quickly remove liquid and stop gas supply to help maintain equipment and process stability; and promptly detect and address the ingress of backwash liquid to reduce potential process risks and damage.

[0085] In this example, see Figure 9 and Figure 11 The side surface of the liquid leakage port 80 is tilted relative to the vertical plane.

[0086] In this example, see Figure 9 and Figure 11 The inclination angle of the side surface of the above-mentioned leakage port 80 relative to the vertical plane is less than 120°.

[0087] The sides of leakage port 80 are tilted at an angle of less than 120° relative to the vertical, optimizing the liquid flow path, allowing liquid to flow more efficiently into the drainage pipe and reducing liquid retention and accumulation near leakage port 80. Specifically, the tilt helps guide liquid into the drainage pipe more quickly, reducing liquid retention; the appropriate angle prevents liquid accumulation at leakage port 80, reducing the possibility of blockage; and a smoother liquid flow path helps maintain process stability and continuity.

[0088] Of course, in other embodiments, the aforementioned tilt angle may be other values ​​and is not limited to the values ​​mentioned in this embodiment.

[0089] In this example, see Figure 10 The number of the above-mentioned leakage ports 80 can be 10. Of course, in other embodiments, the number can be other numbers, which can be set according to actual conditions.

[0090] In addition, a plurality of liquid leakage ports 80 may be arranged at intervals in the outer tank 12 .

[0091] The working process of the wafer backside cleaning device of this embodiment is similar to that of the previous embodiment, and further includes:

[0092] If the positive pressure suddenly disappears or drops below the set value, the cleaning liquid will enter the positive pressure area. In this case, the cleaning liquid will flow into the drainage pipe through the leakage port 80. The leakage sensor 90 will detect the liquid and send an alarm to the device, indicating that the process is at risk. The device will automatically stop the process to prevent further risks. After the process stops, the gas supply to the positive pressure area will be immediately cut off, and the back suction valve 100 of the drainage pipe will quickly open to suck back the cleaning liquid in the positive pressure area and the drainage pipe, thereby preventing the liquid from potentially affecting the system.

[0093] The wafer backside cleaning apparatus of this embodiment provides multiple leakage ports 80 within the outer groove 12 of the vacuum chuck 10, along with a drain assembly to detect and drain liquid leaks. The sides of the leakage ports 80 are tilted relative to the vertical at an angle of less than 120°. The multiple leakage ports 80 and drain assembly effectively detect and address leakage. The tilted design of the leakage ports 80 helps improve the flow efficiency of the cleaning liquid and prevents accumulation of cleaning liquid.

[0094] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and such modifications or substitutions are intended to be within the scope of protection of the present invention. Therefore, the scope of protection of the present invention shall be subject to the scope of protection of the claims.

Claims

1. A wafer backside cleaning device, characterized in that: include: A vacuum suction cup, a first airway assembly, and a second airway assembly; the vacuum suction cup is provided with an inner groove and an outer groove, and the outer groove is located on the outer periphery of the inner groove; Wherein, the first air channel component is in communication with the inner groove and is used to evacuate the inner groove to adsorb and fix the wafer on the vacuum chuck; The second air channel assembly is in communication with the outer tank and is used to continuously fill the outer tank with compressed gas to form a positive pressure isolation zone at the edge of the wafer, thereby preventing the cleaning liquid from being sucked into the inner tank; The vacuum suction cup is further provided with a plurality of liquid leakage ports, and the plurality of liquid leakage ports are arranged in the outer groove; It also includes a liquid drain component, which is connected to the liquid leakage port to detect whether the outer tank leaks and drain the liquid when the outer tank leaks.

2. The wafer backside cleaning device according to claim 1, characterized in that: A rotating assembly is also included, and the vacuum suction cup is connected above the rotating assembly.

3. The wafer backside cleaning device according to claim 2, characterized in that: The rotating assembly includes a rotating shaft, a coupling, a bearing and a power source, wherein one end of the rotating shaft is connected to the vacuum suction cup; the other end of the rotating shaft is connected to the coupling, and the coupling is connected to the power source.

4. The wafer backside cleaning device according to claim 2, characterized in that: It also includes a plurality of outer sealing rings, which are located between the rotating assembly and the vacuum suction cup; and a plurality of the outer sealing rings are located below the outer groove.

5. The wafer backside cleaning device according to claim 4, characterized in that: The outer sealing ring includes a CDA sealing ring.

6. The wafer backside cleaning device according to claim 2, characterized in that: It also includes an inner sealing ring, which is located between the rotating component and the vacuum suction cup; and a plurality of the inner sealing rings are located below the inner groove.

7. The wafer backside cleaning device according to claim 6, characterized in that: The inner sealing ring includes a VAC sealing ring.

8. The wafer backside cleaning device according to claim 1, characterized in that: The first airway component includes a VAC airway system.

9. The wafer backside cleaning device according to claim 1, characterized in that: The second airway component includes a CDA airway system.

10. The wafer backside cleaning device according to claim 1, characterized in that: The side surface of the liquid leakage port is arranged to be inclined relative to the vertical plane.

11. The wafer backside cleaning device according to claim 1, characterized in that: The inclination angle of the side surface of the liquid leakage port relative to the vertical plane is less than 120°.

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