Single wafer cleaning machine for improving wafer back cleaning quality and cleaning method

Abstract

The invention belongs to the technical field of semiconductor manufacturing, and particularly relates to a single-chip cleaning machine and a cleaning method for improving the back cleaning quality of a wafer, and the single-chip cleaning machine comprises a base which is fixedly provided with a box body; the supporting assembly is arranged in the box body, the supporting assembly comprises a supporting disc, multiple sets of limiting supporting mechanisms are symmetrically arranged at the edge position of the supporting disc, and a wafer is limited and fixed to the upper portion of the supporting disc through the limiting supporting mechanisms; the driving assembly is arranged below the supporting assembly and used for driving the supporting assembly to rotate; the front cleaning assembly comprises a first swing arm arranged on the base, and a cleaning pipe is fixed to the first swing arm; the front surface and the back surface of the wafer are cleaned at the same time, so that the cleaning efficiency is improved; in addition, by arranging the gas cleaning assembly, the surface of the wafer is convenient to dry, the residual cleaning reagent on the surface of the nozzle can be effectively cleaned, the back of the wafer is prevented from being polluted, and the product quality is improved.

Description

Technical Field

[0001] This invention belongs to the field of semiconductor manufacturing technology, specifically a single-wafer cleaning machine and cleaning method for improving the cleaning quality of the back side of wafers. Background Technology

[0002] In modern semiconductor manufacturing, single-wafer cleaning machines are a key piece of equipment, widely used in various stages of integrated circuit manufacturing. Their main function is to remove impurities such as particles, organic matter, and metallic contaminants from the wafer surface, ensuring the smooth progress of subsequent processes. The quality of the cleaning directly affects the device yield and final performance; therefore, improving the cleaning effect and ensuring the cleanliness of both the wafer surface and back side has become a crucial issue in the current semiconductor manufacturing field.

[0003] Traditional single-wafer cleaning machines typically consist of a robotic arm, a carrier tray, nozzles, and a wafer holding mechanism. During operation, the robotic arm removes the wafer from the loading cassette and precisely places it onto the carrier tray. Then, the nozzles spray a chemical cleaning agent to clean both sides of the wafer. During this process, the cleaning agent is sprayed at high speed onto the rotating wafer surface, and the combined action of chemical action and centrifugal force effectively removes contaminants from the wafer surface. Finally, the wafer is rinsed with deionized water and spun dry using high-speed rotation.

[0004] Although existing technologies perform well in cleaning wafer surfaces, in practical applications, some chemical liquid often remains on the surface of the back nozzle. This residual liquid can contaminate the back of the wafer, causing abnormalities on the back of the wafer, which in turn affects product quality and yield.

[0005] Therefore, the present invention provides a single-wafer cleaning machine and cleaning method to improve the cleaning quality of the back side of a wafer. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is: a single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer, comprising:

[0008] A base on which a housing is fixed;

[0009] A support assembly is disposed inside the housing. The support assembly includes a support disk. Multiple sets of limiting support mechanisms are symmetrically arranged on the edge of the support disk. The wafer is limited and fixed above the support disk by the limiting support mechanisms.

[0010] A drive component, disposed below the support component, is used to drive the support component to rotate;

[0011] A front cleaning assembly, the front cleaning assembly including a swing arm disposed on a base, the swing arm having a cleaning tube fixed thereon;

[0012] A back cleaning assembly, the back cleaning assembly including a nozzle disposed at the center of the top of the support plate;

[0013] A gas cleaning assembly, comprising a second swing arm disposed on a base, wherein a gas pipe is fixed on the second swing arm.

[0014] Preferably, the limiting support mechanism includes a support rod fixed to the support plate, a support platform fixed to the top of the support rod, and a limiting block fixed to the top of the support platform.

[0015] Preferably, the drive assembly includes a mounting housing fixed to the base, a turntable rotatably mounted on the top of the mounting housing, a support plate fixed to the top of the turntable, a fixing sleeve fixed at the bottom center of the support plate, a motor fixed in the inner cavity of the mounting housing, and the motor and the fixing sleeve being connected by a transmission belt.

[0016] Preferably, a water collection trough is fixed on the outer wall of the mounting housing, a drain pipe is fixed at the bottom of the water collection trough, a barrier is provided inside the water collection trough, and an adjustment component is provided below the water collection trough to control the raising or lowering of the barrier.

[0017] Preferably, the adjustment assembly includes hydraulic cylinders symmetrically arranged on both sides below the water collection tank. The hydraulic cylinders are fixed above the base, and a vertical rod is fixed to the end of the telescopic rod of the hydraulic cylinder. The vertical rod slides through the water collection tank in a sealed manner, and the enclosure is fixed to the top of the vertical rod.

[0018] Preferably, a connecting pipe is fixed at the bottom of the nozzle, the connecting pipe is rotatably connected to the support plate through a sealed bearing, the end of the connecting pipe away from the nozzle passes through the middle of the fixed sleeve, a movable sleeve is movably fitted at the bottom of the connecting pipe, a water inlet pipe is fixed at the bottom of the movable sleeve, and the water inlet pipe is connected to the water tank inside the base.

[0019] Preferably, a spiral groove is formed on the lower outer wall of the connecting pipe, and a protrusion is fixed on the inner wall of the top opening of the movable sleeve. The protrusion is movably inserted into the spiral groove, and the movable sleeve is connected to the end of the telescopic rod of the hydraulic cylinder through a connecting plate.

[0020] Preferably, the side of the box has an opening, and a closed door is hinged to the outside of the opening, and the closed door is provided with an observation window.

[0021] A cleaning method for improving the cleaning quality of the back side of a wafer, applicable to the aforementioned single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer, includes the following steps:

[0022] S1. Open the closed door, use the external robotic arm to transfer the wafer to be cleaned into the cabinet, and use the limiting support mechanism to support and limit the wafer;

[0023] S2. Close the sealing door, start the drive assembly, and drive the turntable, support plate, limit support mechanism and the chip to rotate synchronously.

[0024] S3. Activate the front cleaning component and the back cleaning component to simultaneously spray cleaning reagent to rinse the front and back of the chip;

[0025] S4. After the cleaning operation is completed, start the gas cleaning component to blow inert gas onto the wafer surface to dry the wafer surface. During the process, it will continue to rotate and simultaneously spin dry the water stains on the back of the wafer.

[0026] S5. Remove the dried wafer and then use the gas cleaning assembly to clean the cleaning reagent on the back cleaning assembly.

[0027] The beneficial effects of this invention are as follows:

[0028] 1. The present invention discloses a single-wafer cleaning machine and cleaning method for improving the cleaning quality of the back side of a wafer. By setting up a structure of a front cleaning component, a back cleaning component and a driving component, cleaning reagent is sprayed onto both the front and back sides of the wafer simultaneously. When the cleaning reagent comes into contact with the rotating wafer, under the action of centrifugal force, the cleaning reagent diffuses from the center to the surrounding area, thereby thoroughly rinsing the wafer. The method of cleaning both the front and back sides simultaneously improves the cleaning efficiency.

[0029] 2. The single-wafer cleaning machine and cleaning method for improving the cleaning quality of the back side of a wafer, as described in this invention, utilizes a gas cleaning component. After the cleaning operation is completed, inert gas is blown onto the wafer surface through an air tube to dry the wafer surface. During this process, the wafer continues to rotate, simultaneously drying the water stains on the back side of the wafer. After the wafer is dried, inert gas is blown onto the nozzle surface through an air tube to clean the cleaning reagent remaining on the nozzle surface. This prevents the back side of the wafer from being contaminated by the cleaning reagent on the nozzle surface during subsequent cleaning processes, thereby improving product quality and reducing the risk of abnormalities on the back side of the wafer. Attached Figure Description

[0030] The invention will now be further described with reference to the accompanying drawings.

[0031] Figure 1 This is a perspective view of the present invention;

[0032] Figure 2 This is a schematic diagram of the internal structure of the box in this invention;

[0033] Figure 3This is a partial structural schematic diagram of the present invention;

[0034] Figure 4 This is a partial structural cross-sectional view of the present invention;

[0035] Figure 5 yes Figure 3 Enlarged view of point A in the middle;

[0036] Figure 6 yes Figure 4 Enlarged view at point B in the middle;

[0037] Figure 7 yes Figure 4 Enlarged view at point C;

[0038] Figure 8 This is a flowchart of the method of the present invention.

[0039] In the diagram: 1. Base; 2. Box body; 3. Enclosed door; 4. Swing arm one; 5. Cleaning pipe; 6. Swing arm two; 7. Air pipe; 8. Turntable; 9. Water collection tank; 10. Enclosure; 11. Support plate; 12. Limiting support mechanism; 13. Nozzle; 14. Water inlet pipe; 15. Mounting housing; 16. Hydraulic cylinder; 17. Vertical rod; 18. Motor; 19. Transmission belt; 20. Fixed sleeve; 21. Connecting pipe; 22. Connecting plate; 23. Support rod; 24. Support platform; 25. Limiting block; 26. Drain pipe; 27. Movable sleeve; 28. Spiral groove; 29. ​​Protrusion. Detailed Implementation

[0040] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0041] Example 1: As Figures 1 to 7 As shown in the embodiment of the present invention, a single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer includes:

[0042] Base 1, on which a box 2 is fixed;

[0043] A support assembly is disposed inside the housing 2. The support assembly includes a support disk 11. Multiple sets of limiting support mechanisms 12 are symmetrically arranged on the edge of the support disk 11. The wafer is limited and fixed above the support disk 11 by the limiting support mechanisms 12.

[0044] A drive component, disposed below the support component, is used to drive the support component to rotate;

[0045] A front cleaning assembly, the front cleaning assembly including a swing arm 4 disposed on a base 1, and a cleaning tube 5 fixed on the swing arm 4;

[0046] A back cleaning assembly, the back cleaning assembly including a nozzle 13 disposed at the top center of the support plate 11;

[0047] A gas cleaning assembly, the gas cleaning assembly including a swing arm 6 disposed on a base 1, and a gas pipe 7 fixed on the swing arm 6;

[0048] The base 1 is equipped with a container for storing cleaning reagents and inert gas. The cleaning tube 5 and the gas tube 7 are connected to the corresponding containers, and a pump body is provided for pumping the reagents and gas. The container, pump body, swing arm 1 4 and swing arm 2 6 are all existing technologies. Their specifications, installation methods and usage methods are well known to those skilled in the art, and will not be described in detail here.

[0049] During operation, an external robotic arm transfers the wafer to be cleaned into the housing 2 and places it on the limiting support mechanism 12. The limiting support mechanism 12 supports and limits the wafer to ensure stability during rotation. Then, the drive assembly is activated to drive the turntable 8, support plate 11, limiting support mechanism 12, and wafer to rotate synchronously. Next, the swing arm 4 is activated to drive the cleaning tube 5 to rotate above the wafer, so that the outlet of the cleaning tube 5 is facing the top center of the wafer. Cleaning reagent is sprayed onto the front and back of the wafer simultaneously through the front cleaning tube 5 and the back nozzle 13. When the cleaning reagent comes into contact with the rotating wafer, under the action of centrifugal force, the cleaning reagent diffuses from the center to the surrounding area, thereby thoroughly rinsing the wafer. The simultaneous cleaning of the front and back improves cleaning efficiency.

[0050] After the cleaning operation is completed, the spraying of cleaning reagent is stopped, and the air tube 7 is reset using the first cantilever. Then, the gas cleaning assembly is started, and the air tube 7 is rotated above the wafer using the second cantilever. Inert gas (such as nitrogen) is blown onto the wafer surface through the air tube 7 to dry the wafer surface. During this process, the wafer continues to rotate, and the water stains on the back of the wafer are spun off simultaneously. After the wafer is dried, it is removed, and inert gas is blown onto the surface of the nozzle 13 again using the air tube 7 to clean the cleaning reagent remaining on the surface of the nozzle 13. This prevents the back of the wafer from being contaminated by the cleaning reagent on the surface of the nozzle 13 during subsequent cleaning processes, thereby improving product quality and reducing the risk of abnormalities on the back of the wafer.

[0051] The limiting support mechanism 12 includes a support rod 23 fixed on the support plate 11. A support platform 24 is fixed to the top of the support rod 23, and a limiting block 25 is fixed to the top of the support platform 24. During operation, the wafer is placed on the top of the support platform 24. Multiple sets of symmetrically arranged support platforms 24 support the bottom edge of the wafer. At the same time, the limiting block 25 limits the side edge of the wafer to prevent the wafer from being thrown out during rotation. Thus, the wafer can be stably limited on the limiting support mechanism 12.

[0052] The drive assembly includes a mounting housing 15 fixed to a base 1. A turntable 8 is rotatably mounted on the top of the mounting housing 15. A support plate 11 is fixed to the top of the turntable 8. A fixing sleeve 20 is fixed to the center of the bottom of the support plate 11. A motor 18 is fixed in the inner cavity of the mounting housing 15. The motor 18 and the fixing sleeve 20 are connected by a transmission belt 19. During operation, the motor is started, and the power of the motor is transmitted to the fixing sleeve 20 through the transmission belt 19, thereby driving the fixing sleeve 20 to rotate. This, in turn, drives the turntable 8, the support plate 11, the limiting support mechanism 12, and the wafer to rotate, thereby improving the cleaning efficiency of the wafer.

[0053] A water collection tank 9 is fixed on the outer wall of the mounting housing 15. A drain pipe 26 is fixed at the bottom of the water collection tank 9. A baffle 10 is provided inside the water collection tank 9. An adjustment component is provided below the water collection tank 9. The adjustment component controls the baffle 10 to be raised or lowered. One end of the drain pipe 26 extends from the water collection tank 9 to the outside of the box 2 and is connected to an external collection bucket for collecting used reagents.

[0054] The adjustment assembly includes hydraulic cylinders 16 symmetrically arranged on both sides below the water collection tank 9. The hydraulic cylinders 16 are fixed above the base 1. The telescopic rod end of the hydraulic cylinder 16 is fixed with a vertical rod 17. The vertical rod 17 is sealed and slides through into the water collection tank 9, and the enclosure 10 is fixed to the top of the vertical rod 17.

[0055] During operation, firstly, the telescopic rod of the hydraulic cylinder 16 is retracted, thereby driving the vertical rod 17 to move downward, causing the barrier 10 to move downward until it is below the horizontal plane of the limiting support mechanism 12, thus avoiding obstruction to the wafer placement operation. After the wafer is placed on the limiting support mechanism 12, the telescopic rod of the hydraulic cylinder 16 is extended, thereby driving the vertical rod 17 and the barrier 10 to move upward, so that the top of the barrier 10 is higher than the limiting support mechanism 12. In this way, during the wafer cleaning process, the reagents thrown out by centrifugal force will be intercepted by the barrier 10 and fall into the water collection tank 9 below. This can effectively prevent reagent splashing and facilitate the collection of used reagents.

[0056] A connecting pipe 21 is fixed to the bottom of the nozzle 13. The connecting pipe 21 is rotatably connected to the support plate 11 through a sealed bearing. The end of the connecting pipe 21 away from the nozzle 13 passes through the middle of the fixed sleeve 20. A movable sleeve 27 is movably fitted at the bottom of the connecting pipe 21. A water inlet pipe 14 is fixed at the bottom of the movable sleeve 27. The water inlet pipe 14 is connected to the water tank inside the base 1. The water inlet pipe 14 is a flexible hose and is long enough. During operation, a pump is installed inside the water tank, which can transport the cleaning reagent in the water tank to the nozzle 13 through the water inlet pipe 14, the movable sleeve 27 and the connecting pipe 21, and spray it on the back of the wafer to achieve cleaning of the back of the wafer.

[0057] The lower outer wall of the connecting pipe 21 is provided with a spiral groove 28, and the upper open inner wall of the movable sleeve 27 is fixed with a protrusion 29. The protrusion 29 is movably inserted into the spiral groove 28, and the movable sleeve 27 is connected to the end of the telescopic rod of the hydraulic cylinder 16 through the connecting plate 22.

[0058] During operation, when the telescopic rod of the hydraulic cylinder 16 extends, it drives the movable sleeve 27 to move upward with the help of the connecting plate 22. During this process, the connecting pipe 21 moves relatively towards the inside of the movable sleeve 27, causing the protrusion 29 on the inner wall of the top opening of the movable sleeve 27 to move along the spiral groove 28 on the outer wall of the connecting pipe 21, thereby pushing the connecting pipe 21 to rotate, which in turn drives the nozzle 13 at its top to rotate. After the cleaning operation is completed, the telescopic rod of the hydraulic cylinder 16 retracts. At this time, the connecting plate 22 and the movable sleeve 27 are driven to move in opposite directions, thereby driving the nozzle 13 to reverse. By driving the nozzle 13 to rotate, the residual cleaning agent adhering to the surface of the nozzle 13 can be thrown out, so as to achieve the initial cleaning of the nozzle 13 before the air blowing cleaning. This operation reduces the workload of the subsequent cleaning of the cleaning agent on the surface of the nozzle 13 using the gas cleaning component, thereby shortening the cleaning time.

[0059] Example 2: Figure 1 As shown in the first embodiment, another embodiment of the present invention is as follows: the side of the housing 2 is provided with an opening, and a closed door 3 is hinged to the outside of the opening. An observation window is provided on the closed door 3. During operation, the placement and removal of the wafer are carried out with the help of the closed door 3, and the internal working status is observed with the observation window.

[0060] like Figure 8 As shown, a cleaning method for improving the cleaning quality of the back side of a wafer, applicable to the aforementioned single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer, includes the following steps:

[0061] S1. Open the closed door 3, use the external robotic arm to transfer the wafer to be cleaned into the box 2, and use the limiting support mechanism 12 to support and limit the wafer;

[0062] S2. Close the sealing door 3, start the drive assembly, and drive the turntable 8, support plate 11, limit support mechanism 12 and the chip to rotate synchronously.

[0063] S3. Activate the front cleaning component and the back cleaning component to simultaneously spray cleaning reagent to rinse the front and back of the chip;

[0064] S4. After the cleaning operation is completed, start the gas cleaning component to blow inert gas onto the wafer surface to dry the wafer surface. During the process, it will continue to rotate and simultaneously spin dry the water stains on the back of the wafer.

[0065] S5. Remove the dried wafer and then use the gas cleaning assembly to clean the cleaning reagent on the back cleaning assembly.

[0066] The terms "front," "back," "left," "right," "top," and "bottom" all refer to the figures in the accompanying drawings. Figure 1 Based on the perspective of the observer, the side of the device facing the observer is defined as the front, the left side of the observer is defined as the left, and so on.

[0067] In the description of this invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this invention.

[0068] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A single-wafer cleaning machine for improving the cleaning quality of the back side of wafers, characterized in that: include: A base (1), on which a box (2) is fixed; A support assembly is set inside the housing (2). The support assembly includes a support disk (11). Multiple sets of limiting support mechanisms (12) are symmetrically arranged on the edge of the support disk (11). The wafer is limited and fixed above the support disk (11) by the limiting support mechanism (12). A drive component, disposed below the support component, is used to drive the support component to rotate; A front cleaning assembly, the front cleaning assembly including a swing arm (4) disposed on a base (1), and a cleaning tube (5) fixed on the swing arm (4); A back cleaning assembly, the back cleaning assembly including a nozzle (13) disposed at the center of the top of the support plate (11); A gas cleaning assembly, comprising a second swing arm (6) disposed on a base (1), wherein a gas pipe (7) is fixed on the second swing arm (6).

2. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 1, characterized in that: The limiting support mechanism (12) includes a support rod (23) fixed on the support plate (11), a support platform (24) fixed at the top of the support rod (23), and a limiting block (25) fixed at the top of the support platform (24).

3. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 2, characterized in that: The drive assembly includes a mounting housing (15) fixed on a base (1), a turntable (8) rotatably mounted on the top of the mounting housing (15), a support plate (11) fixed on the top of the turntable (8), a fixing sleeve (20) fixed at the bottom center of the support plate (11), a motor (18) fixed in the inner cavity of the mounting housing (15), and the motor (18) and the fixing sleeve (20) being connected by a transmission belt (19).

4. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 3, characterized in that: A water collection trough (9) is fixed on the outer wall of the mounting housing (15), and a drain pipe (26) is fixed at the bottom of the water collection trough (9). A barrier (10) is provided inside the water collection trough (9), and an adjustment component is provided below the water collection trough (9). The barrier (10) is raised or lowered by the adjustment component.

5. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 4, characterized in that: The adjustment assembly includes hydraulic cylinders (16) symmetrically arranged on both sides below the water collection tank (9). The hydraulic cylinders (16) are fixed above the base (1). A vertical rod (17) is fixed to the end of the telescopic rod of the hydraulic cylinder (16). The vertical rod (17) slides through the water collection tank (9) in a sealed manner, and the enclosure (10) is fixed to the top of the vertical rod (17).

6. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 5, characterized in that: The nozzle (13) is fixed with a connecting pipe (21) at the bottom. The connecting pipe (21) is rotatably connected to the support plate (11) through a sealed bearing. The end of the connecting pipe (21) away from the nozzle (13) passes through the middle of the fixed sleeve (20). The bottom of the connecting pipe (21) is movably fitted with a movable sleeve (27). The bottom of the movable sleeve (27) is fixed with a water inlet pipe (14). The water inlet pipe (14) is connected to the water tank inside the base (1).

7. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 6, characterized in that: The lower outer wall of the connecting pipe (21) is provided with a spiral groove (28), and a protrusion (29) is fixed on the inner wall of the top opening of the movable sleeve (27). The protrusion (29) is movably inserted into the spiral groove (28), and the movable sleeve (27) is connected to the end of the telescopic rod of the hydraulic cylinder (16) through the connecting plate (22).

8. A single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer according to claim 7, characterized in that: The box (2) has an opening on its side, and a closed door (3) is hinged to the outside of the opening. An observation window is provided on the closed door (3).

9. A cleaning method for improving the cleaning quality of the back side of a wafer, the method being applicable to the single-wafer cleaning machine for improving the cleaning quality of the back side of a wafer as described in claim 8, characterized in that: Includes the following steps: S1. Open the closed door (3), use the external robotic arm to transfer the wafer to be cleaned into the box (2), and use the limiting support mechanism (12) to support and limit the wafer; S2. Close the closed door (3), start the drive assembly, and drive the turntable (8), support plate (11), limit support mechanism (12) and the wafer to rotate synchronously; S3. Activate the front cleaning component and the back cleaning component to simultaneously spray cleaning reagent to rinse the front and back of the chip; S4. After the cleaning operation is completed, start the gas cleaning component to blow inert gas onto the wafer surface to dry the wafer surface. During the process, it will continue to rotate and simultaneously spin dry the water stains on the back of the wafer. S5. Remove the dried wafer and then use the gas cleaning assembly to clean the cleaning reagent on the back cleaning assembly.

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