Wafer cleaning chuck and wafer cleaning apparatus

Abstract

The application relates to the field of semiconductor process equipment, and discloses a wafer cleaning chuck and a wafer cleaning device. A plurality of clamping components are distributed along the edge of a mounting base, and the clamping components form a platform for accommodating a wafer and can exert pressure on the edge of the wafer. The plurality of clamping components at least include a first group of clamping components and a second group of clamping components, and the first group of clamping components and the second group of clamping components can be switched between a clamping state and a release state. In the application, the lower elastic film and the upper elastic film cooperate to exert clamping force on the upper and lower surfaces of the edge of the wafer, so that the wafer is intermittently clamped and fixed. The application not only reduces the stress generated when the lower elastic film and the upper elastic film clamp the edge of the wafer, but also makes the stress of the edge of the wafer be temporarily released, which helps to reduce the risk of wafer warping or edge chipping, and solves the problem that the existing clamping mode can cause partial defects in the wafer cleaning process.

Description

Technical Field

[0001] This application relates to the field of semiconductor process equipment technology, and in particular to a wafer cleaning chuck and wafer cleaning equipment. Background Technology

[0002] In semiconductor manufacturing, the cleanliness of the wafer surface directly affects the reliability of the final device. However, during critical processes such as deposition, plasma etching, photoresist spin coating, photolithography, and electroplating, various contaminants can easily be introduced onto the wafer surface, leading to a decrease in cleanliness and severely impacting the production yield of semiconductor devices. Therefore, to remove these contaminants, it is essential to thoroughly clean the wafer using specialized cleaning equipment after wafer processing.

[0003] During wafer cleaning, the wafer is typically secured to a chuck in the cleaning equipment. The chuck clamps and releases the wafer. Currently, mechanical chucks secure the wafer by making point or line contact between the jaws and the wafer edge. This can lead to localized defects during the wafer cleaning process. The main reason is that the jaws create dead zones and stress when clamping the wafer. Dead zones prevent the cleaning fluid from flowing evenly, creating cleaning blind spots and, in severe cases, causing wavy defects on the surface. Stress can cause the wafer edge to concave inward or deform into a "bowl-shaped" or "saddle-shaped" shape. When the substrate bends and the wafer breaks due to shear force, the pattern on the wafer surface collapses, resulting in localized defects. Summary of the Invention

[0004] This application proposes a wafer cleaning chuck and wafer cleaning equipment, which has the advantage of improving the flatness of the wafer surface, thereby solving the problems mentioned in the background art.

[0005] To achieve the above objectives, this application adopts the following technical solution: This application discloses a wafer cleaning chuck, comprising: a mounting base capable of being driven to rotate; multiple clamping components distributed along the edge of the mounting base, forming a platform for accommodating wafers, the clamping components being capable of applying pressure to the edge of the wafer; the multiple clamping components include at least a first set of clamping components and a second set of clamping components, the first set of clamping components and the second set of clamping components being capable of switching between a clamping state and a released state; multiple adjusting components 500, each adjusting component being capable of adjusting its corresponding clamping component; when the mounting base rotates within a preset first speed range, the adjusting components can adjust the first set of clamping components to be in a clamping state to fix the wafer, and the second set of clamping components to be in a released state; when the mounting base rotates at a preset second speed, the first set of clamping components is in a released state, and the second set of clamping components is in a clamping state to fix the wafer.

[0006] In this invention, when the mounting base is rotated, it will drive the clamping component and the adjusting component 500 to rotate. When the rotation speed is within the first speed range, the adjusting component 500 will control the first set of clamping components to be in the clamping state to fix the wafer, while the second set of clamping components is in the released state. When the wafer cleaning fluid cleans the wafer, only the area clamped by the first set of clamping components is not cleaned. When the rotational speed is within the second speed range, the adjusting component 500 controls the first set of clamping components to be in the released state, and the second set of clamping components to be in the clamping state, thereby fixing the wafer. When the wafer cleaning fluid cleans the wafer, the area previously clamped by the first set of clamping components will be cleaned, and the area clamped by the second set of clamping components after being cleaned will be clamped, thereby achieving intermittent clamping of the wafer, thus avoiding permanent dead zones during the wafer cleaning process. Compared with the existing mechanical chuck clamping method, the rotational speed is used to control the switching between clamping and releasing states of different sets of clamping components. By changing the rotational speed of the mounting base, the originally clamped area is exposed, so that it can be rinsed by the cleaning fluid and blown by the gas, thereby achieving full-surface cleaning without dead angles.

[0007] In the wafer cleaning chuck and wafer cleaning equipment provided by this invention, multiple extrusion sections are evenly distributed and divided into several groups. The working state of the moving clamp and the fixed clamp in each group is controlled by the extrusion sections in different groups to achieve intermittent clamping of the wafer, thereby avoiding permanent dead zones during the wafer cleaning process. During the process, with the cooperation of the lower elastic membrane and the upper elastic membrane, clamping force is applied to the upper and lower surfaces of the wafer edge to clamp and fix the wafer. This not only reduces the stress generated when the lower and upper elastic membranes clamp the wafer edge, but also reduces the continuous friction time of the wafer, thereby reducing the risk of particle generation due to friction. It also allows the stress at the wafer edge to be released temporarily, which helps to reduce the risk of wafer warping or edge chipping. This solves the problem that existing mechanical chucks fix the wafer edge by local point or line contact between the jaws and the wafer edge, which can lead to local defects during the wafer cleaning process. Attached Figure Description

[0008] The accompanying drawings, which form part of this specification, illustrate embodiments disclosed in this application and, together with the specification, serve to explain the principles of this application in a clear and understandable manner.

[0009] This disclosure will become clearer with reference to the accompanying drawings and the following detailed description, wherein: Figure 1 This is a schematic diagram of the overall appearance and structure of the present invention; Figure 2 This is a schematic diagram of the base structure of the present invention; Figure 3 This is a schematic diagram of the cover plate structure of the present invention; Figure 4 This is a schematic diagram of the overall half-section of the present invention; Figure 5 for Figure 4 Enlarged view of point A in the middle; Figure 6 This is a half-sectional schematic diagram of the movable clamp of the present invention; Figure 7 This is an exploded view of the extrusion section of the present invention.

[0010] The components are as follows: 100, base; 200, lower half-groove; 300, cover plate; 400, upper half-groove; 500, adjusting component; 510, pressing block; 520, connecting groove; 530, mounting groove; 540, rectangular ring; 600, housing; 700, base plate; 800, moving clamp; 810, connecting pipe; 820, moving housing sleeve; 830, upper elastic membrane; 840, notch; 850, exhaust valve; 860, sealing ring; 870, spring; 900, fixed clamp; 910, fixed housing sleeve; 920, lower elastic membrane; 1000, return air passage; 1100, return air valve; 1200, pressure stabilizing passage; 1300, pressure stabilizing valve; 1400, buffer pad. Detailed Implementation

[0011] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0012] In wafer cleaning processes, the chuck is the core component that holds the wafer and rotates it at high speed. Currently, the mainstream mechanical clamping method mainly refers to edge clamping, where mechanical claws around the chuck grasp the wafer edge through point or line contact. This can lead to localized defects during the wafer cleaning process.

[0013] The inventors discovered that the main causes were dead zones and stress. After clamping the wafer, the mechanical gripper occupies a portion of the wafer's edge area, directly obstructing the direct spray of chemicals and airflow from the nozzle. The high-speed rotation of the airflow creates vortices or low-pressure zones at the gripper, resulting in extremely slow flow of the chemicals, or even stagnation. During the drying stage, residual liquid is easily "pinned" at the gripper edges due to surface tension, making it difficult to be ejected by centrifugal force. After drying, residual liquid leaves annular watermarks or chemical crystals in this area, causing localized defects. Furthermore, to resist the centrifugal force at high speeds, the clamping force is set too high after clamping the wafer. This generates enormous local compressive stress at the contact point, causing the wafer edge to concave inwards. The shear force generated by the substrate bending further breaks the wafer, disrupting the original stress balance and leading to pattern layer peeling or collapse.

[0014] Please see Figure 1-7 This application discloses a wafer cleaning chuck, comprising: The mounting base is capable of being driven to rotate. Multiple clamping components are distributed along the edge of the mounting base, forming a platform for accommodating the wafer. The clamping components are capable of applying pressure to the edge of the wafer. The multiple clamping components include at least a first set of clamping components and a second set of clamping components, which are capable of switching between a clamping state and a released state, respectively. Multiple adjustment components 500, each adjustment component can adjust its corresponding clamping component; when the mounting base rotates within a preset first speed range, the adjustment component can adjust the first set of clamping components to be in a clamping state to fix the wafer, and the second set of clamping components to be in a released state; when the mounting base rotates at a preset second speed, the first set of clamping components is in a released state, and the second set of clamping components is in a clamping state to fix the wafer.

[0015] Because the present invention has the above features, when the mounting base is driven to rotate, it will drive the clamping component and the adjusting component 500 to rotate. When the rotation speed is within the first speed range, the adjusting component 500 will control the first set of clamping components to be in the clamping state to fix the wafer, while the second set of clamping components is in the released state. When the wafer cleaning fluid cleans the wafer, only the area clamped by the first set of clamping components is not cleaned. When the rotational speed is within the second speed range, the adjusting component 500 controls the first set of clamping components to be in the released state and the second set of clamping components to be in the clamping state, thereby fixing the wafer. When the wafer cleaning fluid cleans the wafer, the area previously clamped by the first set of clamping components will be cleaned, and the area clamped by the second set of clamping components after being cleaned will be clamped, thereby achieving intermittent clamping of the wafer and avoiding permanent dead zones during the wafer cleaning process.

[0016] Please see Figure 1-7 The clamping assembly includes a housing 600, a movable clamp 800, and a fixed clamp 900. The internal cavity of the housing 600 is connected to the control cavity. A base plate 700 is fixedly connected inside the housing 600. A buffer pad 1400 is fixedly connected to the inner side of the housing 600. At 0-500 RPM, the wafer is located inside the buffer pad 1400. During rotation, the wafer will be kept in a centered state. Please see Figure 1-7 The movable clamp 800 is disposed inside the housing 600 and is used to clamp and release the upper surface of the wafer. The movable clamp 800 includes a connecting tube 810, and a movable housing 820 is movably sleeved on the curved surface of the connecting tube 810. An upper elastic membrane 830 is fixedly connected to the bottom of the movable housing 820. A notch 840 is opened at one end of the connecting tube 810 connected to the housing 600, and an exhaust valve 850 is fixedly installed inside it for one-way communication between the inside of the movable housing 820 and the connecting tube 810. A sealing ring 860 is fixedly installed at one end of the movable housing 820 near the connecting tube 810, and two springs 870 are fixedly connected to this end for pushing the movable housing 820 to reset.

[0017] Its function is as follows: In the initial stage, the gas inside the housing 600 will first push the moving housing 820 along the connecting pipe 810 and the base plate 700 towards the center of the base 100; in the clamping stage, the gas will enter the interior of the moving housing 820, thereby causing the upper elastic membrane 830 to undergo elastic deformation. With the cooperation of the fixed clamp 900 and the upper elastic membrane 830, the wafer is clamped and fixed by applying clamping force on the upper and lower surfaces of the wafer edge; in the holding stage, the upper elastic membrane 830 will continue to undergo elastic deformation to a certain extent, still clamping and fixing the wafer; in the releasing stage, the elastic deformation of the upper elastic membrane 830 decreases and it no longer contacts the wafer.

[0018] Please see Figure 1-7 The fixed clamp 900 is fixedly installed inside the housing 600 and communicates with the housing 600. It is used to clamp the bottom surface of the wafer and lift the wafer height. The fixed clamp 900 includes a fixed housing sleeve 910 and a lower elastic membrane 920. The lower elastic membrane 920 is fixedly installed on the top of the fixed housing sleeve 910, and its upper surface is flush with the upper surface of the fixed housing sleeve 910. Its function is that when gas enters the interior of the fixed housing sleeve 910, it will cause the lower elastic membrane 920 to undergo elastic deformation, lifting the wafer. When the lower elastic membrane 920 returns to its original state and the compressed gas is discharged from the interior of the fixed housing sleeve 910, it will cause the wafer to descend. When used in conjunction with the upper elastic membrane 830, it can achieve clamping and releasing of the wafer.

[0019] It should be noted that in this invention, the lower elastic membrane 920 and the upper elastic membrane 830 are deformed by air pressure control, and clamping force is applied to the upper and lower surfaces of the wafer edge to clamp and fix the wafer. This transforms the point contact or line contact of the existing chuck into a flexible area contact. Moreover, the lower elastic membrane 920 and the upper elastic membrane 830 can adapt to the slight unevenness of the wafer surface and apply a more uniform clamping force, avoiding edge chipping caused by excessive local stress. When the lower elastic membrane 920 and the upper elastic membrane 830 clamp the wafer, they do not easily generate hard wear debris. Even if a small amount of wear occurs, the properties of the elastomer can reduce the transfer of particles to the wafer surface. Furthermore, when the edge of the wafer is loosened, the cleaning fluid or cleaning gas will carry away the small amount of wear debris from the wafer. During the wafer clamping process, the wafer is lifted, so that the back side of the wafer no longer comes into contact with the chuck surface. A physical gap is formed between the back side of the wafer and the chuck substrate. The cleaning fluid or cleaning gas cleans both sides of the wafer at the same time, thus cleaning the back side without flipping the wafer, and further eliminating the cleaning dead zone on the back side of the wafer.

[0020] Please see Figure 1-7 The mounting base includes a base 100 and a cover plate 300. The base 100 has multiple lower half-grooves 200 inside. The cover plate 300 is fixedly installed on the top of the base 100. The bottom surface of the cover plate 300 has multiple upper half-grooves 400. The upper half-grooves 400 and the lower half-grooves 200 form a control cavity, which is filled with compressed gas. The upper part of the upper half of the trough 400 is connected to the return gas passage 1000. The return gas passage 1000 is fixedly installed with a return gas valve 1100, which is configured to allow gas to flow unidirectionally from the inner end to the outer end of the control chamber.

[0021] Please see Figure 1-7 The adjusting component 500 is slidably connected inside the control cavity. The adjusting component 500 includes a squeezing block 510. The bottom surface of the squeezing block 510 is provided with a connecting groove 520. When the squeezing block 510 moves to a preset position, the pressure stabilizing channel 1200 is connected to the inner end of the control cavity. The surface of the squeezing block 510 is provided with a mounting groove 530. A rectangular ring 540 made of elastic material is fixedly installed inside the mounting groove 530 to isolate the gas on both sides of the squeezing block 510.

[0022] In this invention, the end closer to the center of the base 100 is the inner end, and the end farther from the center of the base 100 is the outer end. The release state includes an initial stage, a clamping stage, and a release stage; the clamping state only includes the clamping stage. In the initial stage, clamping stage, and clamping stage (only the clamping stage), the pressure at the outer end of the control chamber is greater than the pressure at its inner end, and the pressure at the outer end of the control chamber gradually increases while the pressure at the inner end of the control chamber gradually decreases. This causes the return valve 1100 to remain closed throughout the initial stage, clamping stage, and clamping stage. In the release stage, the pressure at the outer end of the control chamber is greater than the pressure at its inner end, and the pressure at the outer end of the control chamber first decreases and then tends to a stable value, allowing gas to escape. The gas volume is constantly decreasing, while the pressure and gas volume at the inner end of the control chamber gradually increase. At this time, the return valve 1100 is still closed. During the centripetal movement of the extrusion block 510, the gas volume at the inner and outer ends of the control chamber remains constant at first, while the pressure at the outer end of the control chamber is greater than the pressure at the inner end. The pressure at the outer end of the control chamber then decreases, and the pressure at the inner end of the control chamber increases. When the pressure at the inner end of the control chamber is greater than the pressure at the outer end of the control chamber, the return valve 1100 is opened, and the gas at the inner end of the control chamber flows back to the outer end of the control chamber through the return passage 1000.

[0023] Please see Figure 1-7 The bottom of the lower half-slot 200 is connected to a pressure stabilizing channel 1200. A pressure stabilizing valve 1300 is fixedly installed inside the pressure stabilizing channel 1200. The pressure stabilizing valve 1300 is configured to stabilize the pressure at the outer end of the control chamber at a preset value and allow gas to flow unidirectionally from the outer end to the inner end of the control chamber.

[0024] In this invention, the pressure regulating valve 1300 is closed in the initial stage, and is open in the clamping, holding, and releasing stages. However, in the clamping stage, since the inner end of the connecting groove 520 and the pressure regulating channel 1200 are not connected, the outer end and the inner end of the control cavity are still not connected.

[0025] It should be noted that the rectangular ring 540 has a certain degree of compressibility and will not affect the sliding of the extrusion block 510 inside the control cavity. Furthermore, the centrifugal force generated when the rectangular ring 540 rotates can overcome the friction between the rectangular ring 540 and the inner wall of the control cavity. When the connecting groove 520 is connected to the inner end of the pressure regulating channel 1200, the gas pressure at the outer end of the control cavity will cause the pressure regulating valve 1300 to be in the open state. The gas at the outer end of the control cavity will pass through the pressure regulating channel 1200 and enter the inner end of the control cavity. At this time, the elastic deformation of the adjustment component 500 is insufficient to contact the wafer, thus it remains in the loosened stage.

[0026] It should be noted that each control chamber contains compressed gas (outside the extrusion block 510). This compressed gas exerts a centripetal thrust on the extrusion block 510 (since the contact area between the compressed gas and multiple extrusion blocks 510 is the same, this thrust is only related to the gas pressure of the compressed gas and is directly proportional to it). In the initial stage, clamping stage, and holding stage, when stationary, each extrusion block 510 experiences an equal thrust. When the base 100 rotates, it causes all the extrusion blocks 510 to rotate. During rotation, the extrusion blocks 510 generate a force that causes them to move apart. When the centrifugal force is greater than the centripetal thrust applied by the compressed gas, the extrusion block 510 will slide centrifugally, thereby reducing the volume occupied by the compressed gas. Since the total amount of gas inside the control chamber remains unchanged, the reduction in the volume of the compressed gas will actually increase the gas pressure of the compressed gas, thereby increasing the centripetal thrust applied by the compressed gas to the extrusion block 510. When the centripetal thrust is equal to the magnitude of the centrifugal force on the extrusion block 510, the extrusion block 510 will no longer slide. The extrusion block 510 will undergo the above changes in the initial stage, the clamping stage, and the holding stage. Since the positional distance of multiple extrusion blocks 510 is the same when they are in the same working state, the speed range corresponding to the clamping stage of the extrusion blocks 510 in different groups can be achieved by changing the mass of the extrusion blocks 510. Since the magnitude of the centrifugal force on an object is directly proportional to its own mass when other conditions are equal, that is, the greater the mass, the greater the centrifugal force. When the base 100 rotates, it drives all the extrusion blocks 510 to rotate at the same speed. At this time, the greater the mass of the extrusion block 510, the greater the centrifugal force it experiences. The heavier extrusion block 510 slides a farther distance centrifugally inside the control cavity than the lighter extrusion block 510, and it is easier to reach the clamping stage. In other words, the heavier the extrusion block 510, the smaller the speed required to reach the clamping stage. That is, the mass of the extrusion block 510 is inversely proportional to the speed of its corresponding clamping stage. It should be noted that, in one embodiment, multiple extrusion blocks 510 are evenly distributed and divided into two groups. When the clamping components control the clamping assembly to clamp the wafer, the required centrifugal force range of the extrusion blocks 510 is different, i.e., the rotational speed range is different. However, the rotational speed range of all extrusion blocks 510 is within the typical rotational speed range of the corresponding process. The first speed range of the first group of adjustment components 500 is 500-950 RPM, and the second speed range of the second adjustment component 500 is 1050-1050 RPM. When the speed range is 950-1050 RPM, both groups of adjustment components 500 are in the clamping state.

[0027] Will Figure 4 The multiple adjustment components 500 are numbered clockwise, with number 1 being the rightmost adjustment component 500. The specific working states of the clamping components controlled by it are shown in the table below: It should be noted that the extrusion blocks 510 numbered 1, 3, 5, and 7 are heavier, while the extrusion blocks 510 numbered 2, 4, 6, and 8 are lighter.

[0028] At speeds of 500-950 RPM, the centrifugal force experienced by extrusion blocks 510 (1, 3, 5, and 7) is greater, causing their controlled clamping components to enter the clamping state first. Extrusion blocks 510 (2, 4, 6, and 8) experience less centrifugal force, and their controlled clamping components remain in the released state. At speeds of 950-1050 RPM, all extrusion blocks 510's controlled clamping components are in the clamping state. At speeds of 1050-1050 RPM, the centrifugal force experienced by extrusion blocks 510 (1, 3, 5, and 7) is greater, exceeding their preset positions. This causes gas inside the control chamber to flow from the outside to the inside, releasing their controlled clamping components, while extrusion blocks 510 (2, 4, 6, and 8) enter the clamping state.

[0029] The wafer cleaning equipment includes a frame, a drive unit, and the aforementioned wafer cleaning chuck. The drive unit is connected to the mounting base to drive its rotation.

[0030] Working principle: When the wafer cleaning chuck is working, the wafer is placed on the upper surface of the fixed shell sleeve 910 and the lower elastic membrane 920. The wafer is in just contact with multiple buffer pads 1400. Under the action of multiple buffer pads 1400, the center of the upper surface of the wafer cover plate 300 is brought into position. Then the drive device drives the chuck to rotate, and the speed gradually increases. The time required for the speed to increase to the typical speed range is short. During the process, multiple squeezing blocks 510 will move outward along the control cavity under the action of centrifugal force, squeezing the gas outside the control cavity and increasing the gas pressure. In the initial stage, gas enters the interior of housing 600 and fixed housing 910, thereby pushing moving housing 820 along connecting pipe 810 and base plate 700 toward the center of base 100, and at the same time causing lower elastic membrane 920 to undergo elastic deformation, lifting the wafer. When the moving housing 820 is not in contact with the connecting tube 810, it enters the clamping stage (at this time, the upper elastic membrane 830 is completely exposed inside the housing 600). Gas will enter the interior of the moving housing 820, causing the upper elastic membrane 830 to undergo elastic deformation. With the cooperation of the lower elastic membrane 920 and the upper elastic membrane 830, clamping force is applied to the upper and lower surfaces of the wafer edge, thereby lifting and fixing the wafer at the same time. Then, the clamping stage begins. Under the action of centrifugal force, the extrusion block 510 will continue to slide centrifugally along the control cavity until the connecting groove 520 at the bottom of the extrusion block 510 connects with the inner end of the pressure stabilizing channel 1200. When the connecting groove 520 is connected to the inner end of the pressure regulating channel 1200, the gas pressure at the outer end of the control cavity will cause the pressure regulating valve 1300 to be in the open state. The gas at the outer end of the control cavity will pass through the pressure regulating channel 1200 and enter the inner end of the control cavity. At this time, the elastic deformation of the upper elastic diaphragm 830 and the moving housing 820 relative to other adjustment components 500 that are in the clamping state is insufficient to contact the wafer, so they are always in the loosening stage. Since the multiple adjustment components 500 are divided into multiple groups, the range of centrifugal force required by the squeezing block 510 when clamping the wafer is different, that is, the range of rotation speed is different. By changing the rotation speed of the chuck, the intermittent clamping of the multiple adjustment components 500 can be achieved, thereby avoiding the existence of permanent dead zones during the wafer cleaning process. After the wafer cleaning is completed, the chuck speed will gradually decrease. During this process, the upper elastic membrane 830 and the lower elastic membrane 920 will return to their original shapes. This will increase the pressure at the outer end of the control cavity, and the thrust on the pressing block 510 will be greater than the centrifugal force, thus pushing the pressing block 510 to slide centrifugally along the control cavity. At the same time, the spring 870 will push the moving housing 820 to slide centrifugally along the connecting pipe 810, which will further push the pressing block 510 to slide centrifugally along the control cavity. When the moving housing 820 contacts the connecting pipe 810, the upper elastic membrane 830 returning to its original shape will cause the gas pressure inside the moving housing 820 to increase. This will cause the exhaust valve 850 to be in the open state, and the gas inside the moving housing 820 will enter the interior of the connecting pipe 810 and finally enter the interior of the housing 600 through the notch 840. The squeezing block 510 slides centripetally along the control chamber, which causes the gas pressure at the inner end of the control chamber to increase, thereby causing the return valve 1100 to be in the open state, and the gas at the inner end of the control chamber will flow back to the outer end of the control chamber through the return passage 1000.

[0031] As a second aspect of the present invention, a wafer cleaning apparatus is provided, the wafer cleaning apparatus including a frame, a drive device, and a wafer cleaning chuck provided in the embodiments of the present invention; In the wafer cleaning equipment provided by this invention, the wafer cleaning chuck applies clamping force to the upper and lower surfaces of the wafer edge through the cooperation of the lower elastic film 920 and the upper elastic film 830, thereby intermittently clamping and fixing the wafer. Unlike traditional chucks that rely on continuous, rigid mechanical force to fix the wafer, this wafer cleaning equipment is dynamically controlled based on the rotational speed of the chuck. By adjusting the rotational speed of the chuck driven by the drive device, different groups of extrusion components can be directed to switch between the "clamping" and "releasing" states. This ensures that within the speed range allowed by the process, at least one set of clamping devices is in the released state at any given time. This intermittent release mechanism allows the wafer edge area, which was originally covered by the upper elastic film 830 and the lower elastic film 920, to be periodically exposed, allowing the cleaning fluid and purging gas to unobstructedly flush these traditionally "blind spots," truly achieving deep cleaning of the entire wafer surface without dead angles.

[0032] In protecting wafer integrity, the long-term strong clamping of traditional chucks easily leads to stress concentration at the wafer edges, causing microparticle detachment and resulting in serious yield problems such as pattern transfer errors, thin film breakage, or short circuits. This invention, through the alternating tightening and loosening of multiple sets of moving clamps 800 and fixed clamps 900, significantly shortens the continuous friction time between the upper elastic film 830 and the lower elastic film 920 and the wafer edges, reducing the risk of microparticle generation at the source. Simultaneously, the periodic loosening action allows for the immediate release of accumulated stress at the wafer edges, effectively suppressing wafer warping and edge chipping.

[0033] Furthermore, this invention utilizes air pressure to control the deformation of the upper elastic membrane 830 and the lower elastic membrane 920, upgrading traditional point or line contact to flexible area contact. This allows for adaptive and perfect fit to minute unevenness on the wafer surface, applying a uniformly distributed clamping force and avoiding physical damage caused by excessive local stress. Even with minor wear, the properties of the upper elastic membrane 830 and the lower elastic membrane 920 prevent particle transfer to the wafer surface, and the fluid flushing at the moment of release completely removes any remaining particles.

[0034] It should be noted that the wafer clamping process also features an automatic lifting function. When clamping the wafer, the entire wafer is lifted, creating a physical gap between its back side and the chuck substrate. This breaks the traditional limitation of requiring the wafer to be flipped to clean the back side, allowing the cleaning medium to work on both sides of the wafer simultaneously, further eliminating dead zones in the back side cleaning process.

[0035] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0036] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A wafer cleaning chuck, characterized in that, include: The mounting base is capable of being driven to rotate. Multiple clamping components are distributed along the edge of the mounting base, forming a platform for accommodating the wafer. The clamping components are capable of applying pressure to the edge of the wafer. The multiple clamping components include at least a first set of clamping components and a second set of clamping components, which are capable of switching between a clamping state and a released state, respectively. Multiple adjustment components (500) are provided, each capable of adjusting its corresponding clamping component; when the mounting base rotates within a preset first speed range, the adjustment component (500) can adjust the first set of clamping components to be in a clamping state to fix the wafer, and the second set of clamping components to be in a released state; when the mounting base rotates within a preset second speed range, the first set of clamping components is in a released state, and the second set of clamping components is in a clamping state to fix the wafer.

2. The wafer cleaning chuck according to claim 1, characterized in that, The mounting base includes a base (100) and a cover plate (300). The base (100) has multiple lower half-grooves (200) inside. The cover plate (300) is fixedly installed on the top of the base (100). The bottom surface of the cover plate (300) has multiple upper half-grooves (400). The upper half-grooves (400) and the lower half-grooves (200) form a control cavity.

3. The wafer cleaning chuck according to claim 2, characterized in that, The upper part of the upper half of the groove (400) is connected to a return air passage (1000), and a return air valve (1100) is fixedly installed inside the return air passage (1000), which is configured to allow gas to flow unidirectionally from the inner end to the outer end of the control chamber.

4. The wafer cleaning chuck according to claim 3, characterized in that, The bottom of the lower half-slot (200) is connected to a pressure stabilizing channel (1200), and a pressure stabilizing valve (1300) is fixedly installed inside the pressure stabilizing channel (1200). The pressure stabilizing valve (1300) is configured to stabilize the pressure at the outer end of the control chamber at a preset value and allow gas to flow unidirectionally from the outer end to the inner end of the control chamber.

5. The wafer cleaning chuck according to claim 2, characterized in that, The clamping assembly includes a housing (600), a movable clamp (800), and a fixed clamp (900). The internal cavity of the housing (600) is connected to the control cavity. A base plate (700) is fixedly connected inside the housing (600), and a buffer pad (1400) is fixedly connected to the inner side of the housing (600).

6. The wafer cleaning chuck according to claim 5, characterized in that, The movable clamp (800) is disposed inside the housing (600) and is used to clamp and release the upper surface of the wafer. The movable clamp (800) includes a connecting tube (810), and a movable housing sleeve (820) is movably sleeved on the curved surface of the connecting tube (810). An upper elastic membrane (830) is fixedly connected to the bottom of the movable housing sleeve (820). A notch (840) is opened at one end of the connecting tube (810) that is connected to the housing (600), and an exhaust valve (850) is fixedly installed inside it for one-way communication between the inside of the movable housing sleeve (820) and the connecting tube (810).

7. The wafer cleaning chuck according to claim 6, characterized in that, A sealing ring (860) is fixedly installed at one end of the movable housing (820) near the connecting pipe (810), and two springs (870) are fixedly connected to this end for pushing the movable housing (820) to reset.

8. The wafer cleaning chuck according to claim 7, characterized in that, The fixed clamp (900) is fixedly installed inside the housing (600) and communicates with the housing (600) for clamping the bottom surface of the wafer and raising the height of the wafer. The fixed clamp (900) includes a fixed housing sleeve (910) and a lower elastic membrane (920). The lower elastic membrane (920) is fixedly installed on the top of the fixed housing sleeve (910), and its upper surface is flush with the upper surface of the fixed housing sleeve (910).

9. The wafer cleaning chuck according to claim 4, characterized in that, The adjustment component (500) is slidably connected inside the control cavity. The adjustment component (500) includes a squeezing block (510). The bottom surface of the squeezing block (510) is provided with a connecting groove (520). When the squeezing block (510) moves to a preset position, the pressure stabilizing channel (1200) is connected to the inner end of the control cavity. The surface of the squeezing block (510) is provided with a mounting groove (530). A rectangular ring (540) made of elastic material is fixedly installed inside the mounting groove (530) to isolate the gas on both sides of the squeezing block (510).

10. A wafer cleaning equipment, characterized in that, It includes a frame, a drive unit, and a wafer cleaning chuck as described in any one of claims 1 to 9, wherein the drive unit is connected to the mounting base to drive its rotation.

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