Wafer cleaning unit, apparatus and method

Abstract

The application discloses a wafer cleaning unit, device and method. The cleaning unit comprises a modular clean room provided with a multi-channel spray head; a wobble control assembly provided with a connecting cylinder, a movable adapter disc and a transmission seat; a bearing table connected with the transmission seat through a universal joint, the bearing table being provided with a negative pressure adsorption hole; a coaxial double-ring double-frequency ultrasonic transducer, an inner ring of the coaxial double-ring double-frequency ultrasonic transducer working at MHz and an outer ring working at kHz, and the two rings being phase-biased; and a driving mechanism for driving the adapter disc to move up and down and the transmission seat to rotate. The adapter disc is matched with a flow guide groove in the inner wall of the connecting cylinder, so that the cleaning liquid is discharged in a branch way. The double-frequency sound field with adjustable phase is coupled with the micro-tilt wobble of the bearing table, the fluid renewal in the microstructure and the particle detachment capacity are improved, the use amount of the cleaning liquid and the film damage are reduced, and the chemical cross contamination is reduced through branch waste discharge. The device can be integrated into a multi-module device and a corresponding cleaning method is implemented.

Description

Technical Field

[0001] This invention relates to the field of semiconductor manufacturing technology, and in particular to a wafer cleaning unit, apparatus and method. Background Technology

[0002] RCA cleaning is a crucial step between photolithography / etching / deposition to remove particles, organic residues, and metal ions. In the prior art, patent document CN104658947B discloses a wafer cleaning apparatus, including: a cleaning tank with a cavity; a wafer support device disposed within the cavity to support the wafer; and a nozzle capable of spraying liquid or gas toward the wafer. Residual liquid flowing from the first nozzle is collected by a receiving tank to prevent it from spilling outside the cavity and polluting the environment. This wafer cleaning apparatus can perform wafer cleaning with a high degree of automation, high production efficiency, good cleaning effect, and high yield.

[0003] However, in the RCA cleaning process, particles in high aspect ratio grooves / slits are difficult to desorb, and strong ultrasonic or high flow rates can easily cause film erosion and damage to metal wires / porous low-k materials. Based on this, existing RCA cleaning equipment is insufficient in terms of particle removal and film damage, and it is difficult to meet the requirements of advanced nodes for cleanliness and repeatability. Summary of the Invention

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a wafer cleaning unit, equipment, and method.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: a wafer cleaning unit, comprising:

[0006] The modular cleanroom has a cleaning chamber inside. The rear of the modular cleanroom is equipped with an air exchange duct that connects to the cleaning chamber. Multi-channel nozzles are installed inside the modular cleanroom.

[0007] The oscillation control component has a connecting cylinder, which is fixedly installed on the inner bottom wall of the modular clean room. The connecting cylinder is equipped with a vertically movable transfer plate. The transfer plate is rotatably installed inside, and a first magnetic ring and several electromagnetic windings are embedded inside the transfer plate.

[0008] The support platform is connected to the upper surface of the transmission seat via a universal joint. The upper surface of the support platform is provided with a negative pressure hole. The wafer is adsorbed onto the upper surface of the support platform by negative pressure. A second magnetic ring and a third magnetic ring are fixedly installed on the lower surface of the support platform. The first magnetic ring and the second magnetic ring are magnetically repelled. The third magnetic ring is located on the upper side of the electromagnetic winding arranged in a ring array.

[0009] A dual-frequency ultrasonic transducer has an inner ring and an outer ring. The phase offset of the inner and outer rings forms a beat frequency / coupled acoustic current. Both the inner and outer rings are fixedly installed at the top of the connecting cylinder.

[0010] The drive mechanism has a servo electric cylinder and a servo motor. The servo electric cylinder drives the adapter plate and the transmission base to move up and down synchronously, and the servo motor drives the transmission base to rotate.

[0011] Preferably, the bottom of the modular cleanroom is fixedly equipped with a first row of waste pipes, a second row of waste pipes and a third row of waste pipes. The adapter plate is slidably connected to the connecting cylinder. The adapter plate divides the inner cavity of the connecting cylinder into upper and lower chambers. The inner wall of the connecting cylinder is provided with a first guide groove and a second guide groove. The first row of waste pipes is connected to the first guide groove, the second row of waste pipes is connected to the second guide groove, and the third row of waste pipes is connected to the bottom of the cleaning chamber.

[0012] Preferably, the servo electric cylinder is fixedly installed at the bottom of the modular cleanroom. An air sleeve is fixedly installed at the telescopic end of the servo electric cylinder via a bracket. A transmission sleeve is fixedly installed at the upper end of the air sleeve. The transmission sleeve slides through the bottom of the modular cleanroom and extends into the connecting cylinder. The top end of the transmission sleeve is fixedly connected to the adapter plate.

[0013] A drive shaft is rotatably mounted inside the gas sleeve via a mechanical seal. The top end of the drive shaft is fixedly connected to a drive seat. A servo motor is fixedly mounted at the bottom of the gas sleeve, and the rotating end of the servo motor is fixedly connected to the bottom end of the drive shaft.

[0014] The drive shaft has a transfer air chamber inside, and multiple through holes communicating with the transfer air chamber are opened on the surface of the drive shaft. A pumping pipe is fixedly installed on the surface of the air sleeve, and the pumping pipe communicates with the transfer air chamber through the through holes. A connecting hose is installed inside the drive shaft, and the transfer air chamber communicates with the negative pressure hole through the connecting hose.

[0015] Preferably, the servo electric cylinder drives the adapter plate to move up and down synchronously with the transmission base to adjust the height. When the adapter plate is higher than the first guide groove, the passage between the upper chamber of the connecting cylinder and the first and second guide grooves is blocked by the adapter plate. When the adapter plate is located between the first and second guide grooves, the upper chamber of the connecting cylinder is connected to the first guide groove, and the passage between the upper chamber of the connecting cylinder and the second guide groove is blocked by the adapter plate.

[0016] Preferably, the modular cleanroom is rotatably mounted with a mechanical swing arm, and a multi-channel nozzle is fixedly connected to the mechanical swing arm. The mechanical swing arm is equipped with an N2 air curtain nozzle and an IPA steam blade nozzle.

[0017] This application proposes a wafer cleaning device that includes one or more wafer cleaning units. When multiple wafer cleaning units are used, adjacent modular cleanrooms are connected in parallel to form an integrated device.

[0018] This application proposes a wafer cleaning method, including the following steps:

[0019] S1. Loading and pre-rinsing: DI spray for 30–60 seconds, prioritizing DI degassing;

[0020] S2, SC-1: Spray liquid at 70–80℃, dual-frequency ultrasonic transducer provides dual-frequency sound field (outer ring 0.4 W / cm², inner ring 0.1 W / cm²), the support platform rotates to 50-100 rpm, ±8° swing vibration, to remove particles;

[0021] S3, Rinse: High flow rate DI until ORP and conductivity reach the threshold;

[0022] S4, SC-2: Liquid spraying at 25–40℃, dual-frequency ultrasonic transducer provides low-power sound field, N2 air curtain nozzle edge sweeping bubble, improves metal ion complexation and removal;

[0023] S5, Rinse and optional HF light treatment: 0.1–0.5% HF for 15–30 s to remove thin oxide / metal hydroxide, followed by full DI replacement;

[0024] S6. Drying: Use N2 air curtain nozzles for edge drying and IPA steam knife nozzles for full-area drying. The rotating platform is accelerated to 600–800 rpm.

[0025] S7, Unloading and Transfer.

[0026] The present invention has the following beneficial effects:

[0027] 1. The cleaning unit proposed in this invention uses a dual-frequency ultrasonic transducer with an inner and outer ring arranged coaxially. The outer ring provides macroscopic shear and particle desorption force, while the inner ring provides microscale acoustic flow to penetrate microgrooves. The phase offset of the two rings forms beat frequency / coupled acoustic flow, which improves the flow field renewal rate and particle desorption probability inside the microstructure, improves cleanliness, and at the same time reduces the peak local stress on the film, thus reducing film damage.

[0028] 2. The cleaning unit proposed in this invention, by setting up a swing control component and a support platform, uses the slight tilting and low-frequency swinging of the support platform to construct a controllable gravity component and liquid film thickness gradient, thereby reducing the loss of cleaning fluid. The swinging of the support platform is conducive to the discharge of liquid adhering to the edge and bottom of the wafer. The edge N2 air curtain generated by the N2 air curtain nozzle, together with the swinging of the support platform, pulls the liquid film outward in the acceleration phase, inhibiting watermark formation and improving the watermark-free drying rate. At the same time, the swinging causes the particles on the wafer surface to present different angles and couple with the sound field, improving the decontamination efficiency and maintaining production capacity.

[0029] 3. The cleaning unit proposed in this invention, by setting up a connecting cylinder and an adapter plate, uses a servo electric cylinder to drive the adapter plate and the transmission seat to move up and down synchronously. By adjusting the position of the adapter plate, the upper chamber of the connecting cylinder is connected to the first guide channel and the second guide channel respectively. The cleaning solvent is independently selected for the drainage channel according to the chemical category. The SC-2 metal ion-rich flow path is collected separately, which facilitates downstream metal recovery and treatment, reduces cross-contamination and chemical consumption, and improves EHS performance. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall three-dimensional structure of the wafer cleaning equipment proposed in this invention;

[0031] Figure 2 This is a schematic diagram of the three-dimensional structure of the wafer cleaning unit proposed in this invention. Figure 1 ;

[0032] Figure 3 This is a schematic diagram of the three-dimensional structure of the wafer cleaning unit proposed in this invention. Figure 2 ;

[0033] Figure 4 This is a schematic diagram of the three-dimensional structure of the adapter plate and support platform proposed in this invention. Figure 1 ;

[0034] Figure 5 This is a schematic diagram of the three-dimensional structure of the adapter plate and support platform proposed in this invention. Figure 2 ;

[0035] Figure 6 This is a partial cross-sectional structural diagram of the modular cleanroom proposed in this invention. Figure 1 ;

[0036] Figure 7 This is a partial cross-sectional structural diagram of the modular cleanroom proposed in this invention. Figure 2 ;

[0037] Figure 8 This is a partial cross-sectional structural diagram of the modular cleanroom proposed in this invention. Figure 3 ;

[0038] Figure 9 This is a top view of a wafer.

[0039] In the diagram: 1 Modular cleanroom, 2 Multi-channel nozzle, 3 Connecting cylinder, 4 Transfer plate, 5 Transmission seat, 6 First magnetic ring, 7 Electromagnetic winding, 8 Support platform, 9 Universal joint, 11 Wafer, 12 Second magnetic ring, 13 Third magnetic ring, 14 Dual-frequency ultrasonic transducer, 15 Inner ring, 16 Outer ring, 17 Servo electric cylinder, 18 Servo motor, 19 First waste pipe, 20 Second waste pipe, 21 Third waste pipe, 22 First guide channel, 23 Second guide channel, 24 Air jacket, 25 Transmission sleeve, 26 Transmission shaft, 27 Transfer air chamber, 28 Pumping pipe, 29 Perforation, 30 Connecting hose, 31 Mechanical swing arm, 32 N2 air curtain nozzle, 33 Cleaning chamber, 34 Negative pressure hole. Detailed Implementation

[0040] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0041] In the description of this invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "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 limitations on this invention.

[0042] Reference Figure 2 , Figure 3 A wafer cleaning unit includes: a modular cleanroom 1, the interior of which is a cleaning chamber 33; a ventilation duct connected to the cleaning chamber 33 is provided on the rear side of the modular cleanroom 1; a multi-channel nozzle 2 is installed inside the modular cleanroom 1; a mechanical swing arm 31 is rotatably installed inside the modular cleanroom 1; the multi-channel nozzle 2 is fixedly connected to the mechanical swing arm 31; an N2 air curtain nozzle 32 and an IPA vapor blade nozzle are provided on the mechanical swing arm 31; wherein, the mechanical swing arm 31 rotates at a certain angle, so that the multi-channel nozzle 2 moves to the top of the wafer to spray cleaning fluid; and the N2 air curtain nozzle 32 and the IPA vapor blade nozzle are used for drying treatment. This is prior art and will not be described in detail here.

[0043] Shiver control components, reference Figure 6 It has a connecting cylinder 3, which is fixedly installed on the inner bottom wall of the modular cleanroom 1. A movable adapter plate 4 is installed inside the connecting cylinder 3. A transmission seat 5 is rotatably installed inside the adapter plate 4. A first magnetic ring 6 and several electromagnetic windings 7 are embedded inside the adapter plate 4. Figure 4 As shown, several electromagnetic windings 7 are arranged in a ring array;

[0044] Support platform 8, reference Figure 4 , Figure 5 The support platform 8 is connected to the upper surface of the transmission base 5 via a universal joint 9, such as... Figure 5 As shown, a negative pressure hole 34 is provided on the upper surface of the support platform 8. The wafer 11 is adsorbed on the upper surface of the support platform 8 by negative pressure. A second magnetic ring 12 and a third magnetic ring 13 are fixedly installed on the lower surface of the support platform 8. The first magnetic ring 6 and the second magnetic ring 12 are magnetically repelled. The third magnetic ring 13 is located on the upper side of the electromagnetic windings 7 arranged in a ring array. When any electromagnetic winding 7 is energized, a magnetic field is generated to repel or attract the third magnetic ring 13, causing the support platform 8 to tilt.

[0045] Dual-frequency ultrasonic transducer 14, reference Figure 6 It has an inner ring 15 and an outer ring 16, with the outer ring at 20–80 kHz and the inner ring at 0.8–2.0 MHz; the phase offset is adjustable from 30 to 120°; the sound intensity is 0.2–1.2 W / cm²; the sweep frequency is ±50 kHz; the phase offset of the inner ring 15 and the outer ring 16 forms a beat frequency / coupled acoustic current, and both the inner ring 15 and the outer ring 16 are fixedly installed at the top of the connecting cylinder 3;

[0046] The drive mechanism has a servo electric cylinder 17 and a servo motor 18. The servo electric cylinder 17 drives the adapter plate 4 and the transmission seat 5 to move up and down synchronously, and the servo motor 18 drives the transmission seat 5 to rotate.

[0047] Specifically, such as Figure 3 , Figure 6 As shown, the bottom of the modular cleanroom 1 is fixedly equipped with a first row of waste pipes 19, a second row of waste pipes 20 and a third row of waste pipes 21. The adapter plate 4 is slidably connected to the connecting cylinder 3. The adapter plate 4 divides the inner cavity of the connecting cylinder 3 into upper and lower chambers. The inner wall of the connecting cylinder 3 is provided with a first guide groove 22 and a second guide groove 23. The first row of waste pipes 19 is connected to the first guide groove 22, the second row of waste pipes 20 is connected to the second guide groove 23, and the third row of waste pipes 21 is connected to the bottom of the cleaning chamber 33.

[0048] refer to Figure 3 , Figure 6 The servo electric cylinder 17 is fixedly installed at the bottom of the modular cleanroom 1. The telescopic end of the servo electric cylinder 17 is fixedly installed with an air sleeve 24 through a bracket. The upper end of the air sleeve 24 is fixedly installed with a transmission sleeve 25. The transmission sleeve 25 slides through the bottom of the modular cleanroom 1 and extends into the connecting cylinder 3. The top end of the transmission sleeve 25 is fixedly connected to the adapter plate 4. When the servo electric cylinder 17 telescopically moves, it drives the adapter plate 4 to move up and down horizontally.

[0049] A drive shaft 26 is rotatably mounted inside the air sleeve 24 via a mechanical seal. The top end of the drive shaft 26 is fixedly connected to the rotating seat. A servo motor 18 is fixedly mounted at the bottom of the air sleeve 24, and the rotating end of the servo motor 18 is fixedly connected to the bottom end of the drive shaft 26. The servo motor 18 drives the support platform 8 to rotate.

[0050] The drive shaft 26 has a transfer air chamber 27 inside. The surface of the drive shaft 26 has multiple through holes 29 that communicate with the transfer air chamber 27. A pumping pipe 28 is fixedly installed on the surface of the air sleeve 24. The pumping pipe 28 communicates with the transfer air chamber 27 through the through holes 29. A connecting hose 30 is installed inside the transfer shaft. The transfer air chamber 27 communicates with the negative pressure hole 34 through the connecting hose 30. Air is drawn in through the pumping pipe 28, and a negative pressure is generated in the negative pressure hole 34 on the support platform 8, so that the wafer 11 is adsorbed on the support platform 8 without interfering with the rotation of the support platform 8.

[0051] This application proposes a wafer cleaning method, including the following steps:

[0052] S1. Film loading and pre-rinsing: The film is loaded with DI (distilled water) sprayed from the multi-channel nozzle 2 for 30–60 seconds. Before the formal cleaning begins, a preliminary cleaning is performed to remove obvious dirt or easily attached substances, ensuring that the working environment is free of smoke and dust. The film is degassed immediately after spraying to avoid water vapor interfering with subsequent operations.

[0053] S2, SC-1: Place the wafer 11 on the support stage 8, and spray SC-1 cleaning solution from the multi-channel nozzle 2, with the temperature controlled at 70–80℃.

[0054] A high-power acoustic field of 0.4 W / cm² for the outer ring and 0.1 W / cm² for the inner ring is provided using a dual-frequency ultrasonic transducer 14; the ultrasonic vibration time is 15–20 minutes.

[0055] The platform 8 is rotated and tilted at a fixed angle of ±8° with a speed of 50-100 rpm to enhance the cleaning effect;

[0056] S3. Rinsing: The multi-channel nozzle 2 sprays high-flow DI water to rinse the wafer 11 until the ORP (oxidation-reduction potential) threshold is reached; ensure that the rinsing time is sufficient, usually 30–60 seconds, to thoroughly remove residual cleaning solution and impurities;

[0057] S4, SC-2: The multi-channel nozzle 2 sprays SC-2 cleaning fluid at a temperature controlled at 25–40°C. A dual-frequency ultrasonic transducer 14 provides a low-power sound field (e.g., 0.1 W / cm²) to reduce mechanical damage to the wafer surface. At the same time, an N2 air curtain nozzle 32 is used to perform bubble sweeping treatment on the edge area of ​​the wafer 11 to remove hard-to-dissolve dirt or metal oxides.

[0058] S5. Rinsing and optional HF light treatment: Multi-channel nozzles 2 spray high-flow DI water to rinse wafer 11 to ensure thorough removal of residues; in conjunction with the ORP detection system, the rinsing flow rate and time are dynamically adjusted to ensure cleaning effect.

[0059] Optional HF treatment: Use a diluted HF solution (0.1–0.5%, such as 0.3%) to lightly treat the wafer surface to remove the thin oxide layer or metal hydroxide. The treatment time should be controlled within 15–30 seconds to avoid excessive corrosion. An HF sensitivity test should be performed before operation to ensure material tolerance. After treatment, rinse immediately with DI water to thoroughly remove residual HF and prevent wafer surface corrosion.

[0060] S6. Drying: Edge drying: Use N2 air curtain nozzle 32 to locally blow air onto the edge of wafer 11 to prevent excessive moisture in the edge area; Full area drying: Use IPA vapor blade nozzle to intermittently dry the wafer surface to avoid direct hot air drying to prevent wafer deformation. After drying, the stage 8 is rotated to accelerate the wafer to 600-800 rpm to accelerate the air evaporation rate and reduce residual liquid on the surface.

[0061] S7, Unloading and Transfer.

[0062] In the S4 process, the outer ring 16 provides macroscopic shear and particle desorption forces, while the inner ring 15 provides microscale acoustic flow to penetrate the microgroove. The phase offset of the two rings forms beat frequency / coupled acoustic flow, which improves the flow field renewal rate and particle desorption probability inside the microstructure, improves cleanliness, and at the same time reduces the peak local stress on the film, thus reducing film damage.

[0063] refer to Figure 4 In the diagram, the dotted arrow on the upper side of the adapter plate 4 indicates the direction of the magnetic force exerted by the electromagnetic winding 7 on the third magnetic ring 13. When the support platform 8 is rotating, taking point A as an example, when point A of the third magnetic ring 13 rotates to above the #1 electromagnetic winding 7, the #1 electromagnetic winding 7 generates a magnetic attraction force, causing the support platform 8 to tilt downwards (wafer 11 tilts downwards). When point A of the third magnetic ring 13 rotates to above the #2 electromagnetic winding 7, the #2 electromagnetic winding 7 generates a magnetic repulsion force, causing the support platform 8 to tilt upwards. This cycle drives the support platform 8 to swing up and down, realizing the rotation and up-and-down swing of the wafer 11.

[0064] It should be noted that the PLC of the cleaning equipment controls multiple electromagnetic windings 7 according to a preset program through a multi-channel signal output module, so that these electromagnetic windings 7 are powered on and off in a determined order. When the #1 electromagnetic winding 7 is powered on, the electromagnetic windings 7 in other positions are powered off. This is a conventional configuration in the existing technology and will not be described in detail here.

[0065] refer to Figure 9When the wafer 11 rotates and oscillates up and down, under the action of centrifugal force, the cleaning fluid sprayed by the multi-channel nozzle 2 spreads on the surface of the wafer 11. The linear velocity is faster and the centrifugal force is greater in the area away from the center of the wafer 11, and the cleaning fluid is quickly discharged. In other words, the liquid film is thinner away from the center, and more cleaning fluid is needed to achieve the cleaning purpose, which also increases the time. The up and down oscillation of the wafer 11 causes the liquid film on the surface of the wafer 11 to flow back in the direction of centripetal force, which increases the thickness of the liquid film and reduces the amount of cleaning fluid used. It is worth noting that during the cleaning process, the higher the rotation speed of the carrier stage 8, the shorter the residence time of the cleaning fluid on the wafer surface. The lower the rotation speed of the carrier stage 8, the smaller the flow rate of the cleaning fluid spreading, which affects the cleaning efficiency. It is difficult to control the thickness of the liquid film by simply changing the rotation speed of the carrier stage 8.

[0066] By setting up a oscillation control component and a support platform 8, the support platform 8 is slightly tilted and oscillates at low frequency to construct a controllable gravity component and liquid film thickness gradient, reducing the loss of cleaning fluid. The oscillation of the support platform 8 is conducive to the discharge of liquid adhering to the edge and bottom of the wafer 11. The edge N2 air curtain generated by the N2 air curtain nozzle 32, together with the oscillation of the support platform 8, pulls the liquid film outward in the acceleration phase, inhibiting watermark formation and improving the drying watermark-free rate. At the same time, the oscillation causes the particles on the wafer surface to present different angles and couple with the sound field, improving the decontamination efficiency and maintaining production capacity.

[0067] During the cleaning process, the servo electric cylinder 17 drives the adapter plate 4 and the transmission base 5 to move up and down synchronously to adjust the height;

[0068] like Figure 6 As shown, when the adapter plate 4 is higher than the first guide channel 22, the passage between the upper chamber of the connecting cylinder 3 and the first guide channel 22 and the second guide channel 23 is blocked by the adapter plate 4. At this time, under the centrifugal action of the support platform 8, the cleaning waste liquid is discharged to the bottom of the cleaning chamber 33 of the modular clean room 1 and recovered by the third waste pipe 21. It is suitable for the recovery of waste liquid from S1 pre-rinsing, S3, S5 high flow DI water rinsing and S6 drying.

[0069] like Figure 7 As shown, when the adapter plate 4 is located between the first guide channel 22 and the second guide channel 23, the upper chamber of the connecting cylinder 3 is connected to the first guide channel 22, and the passage between the upper chamber of the connecting cylinder 3 and the second guide channel 23 is blocked by the adapter plate 4. The waste liquid generated by SC-1 flows from the first guide channel 22 to the first waste pipe 19 and is recovered from the first waste pipe 19. This is suitable for the recovery of waste liquid from S2 cleaning.

[0070] like Figure 8As shown, when the adapter plate 4 falls to the bottom, the upper chamber of the connecting cylinder 3 is connected to the second guide channel 23. The waste liquid generated by SC-2 flows from the second guide channel 23 to the second waste pipe 20 and is recovered from the second waste pipe 20. This is suitable for the recovery of waste liquid from S4 cleaning. The cleaning solvent selects the discharge channel independently according to the chemical category. Since SC-2 is rich in metal ions, the flow path is collected separately, which facilitates downstream metal recovery and treatment, reduces cross-contamination and chemical consumption, and improves EHS performance.

[0071] This application discloses a wafer cleaning apparatus, which includes one or more wafer cleaning units, such as... Figure 1 The cleaning equipment shown uses a single wafer cleaning unit. When multiple wafer cleaning units are used, adjacent modular cleanrooms 1 are connected in parallel to form an integrated equipment, which meets the needs of batch cleaning and increases production capacity.

[0072] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A wafer cleaning unit, characterized in that, include: Modular cleanroom (1), the interior of which is a cleaning chamber (33), and a ventilation duct connected to the cleaning chamber (33) is provided on the rear side of the modular cleanroom (1). Multi-channel nozzles (2) are installed inside the modular cleanroom (1). The oscillation control assembly has a connecting cylinder (3), which is fixedly installed on the inner bottom wall of the modular clean room (1). The connecting cylinder (3) is provided with a movable transfer plate (4), and a transmission seat (5) is rotatably installed inside the transfer plate (4). The first magnetic ring (6) and several electromagnetic windings (7) are embedded inside the transfer plate (4). The support platform (8) is connected to the upper surface of the transmission seat (5) through a universal joint (9). The upper surface of the support platform (8) is provided with a negative pressure hole (34). The wafer (11) is adsorbed on the upper surface of the support platform (8) by negative pressure. The lower surface of the support platform (8) is fixedly installed with a second magnetic ring (12) and a third magnetic ring (13). The first magnetic ring (6) and the second magnetic ring (12) are magnetically repulsive. The third magnetic ring (13) is located on the upper side of the electromagnetic winding (7) arranged in a ring array. A dual-frequency ultrasonic transducer (14) has an inner ring (15) and an outer ring (16). The phase offset of the inner ring (15) and the outer ring (16) forms a beat frequency / coupled acoustic current. The inner ring (15) and the outer ring (16) are both fixedly installed at the top of the connecting cylinder (3). The drive mechanism has a servo electric cylinder (17) and a servo motor (18). The servo electric cylinder (17) drives the adapter plate (4) and the transmission seat (5) to move up and down synchronously, and the servo motor (18) drives the transmission seat (5) to rotate.

2. The wafer cleaning unit according to claim 1, characterized in that: The bottom of the modular cleanroom (1) is fixedly installed with a first row of waste pipes (19), a second row of waste pipes (20) and a third row of waste pipes (21). The adapter plate (4) is slidably connected to the connecting cylinder (3). The adapter plate (4) divides the inner cavity of the connecting cylinder (3) into upper and lower chambers. The inner wall of the connecting cylinder (3) is provided with a first guide groove (22) and a second guide groove (23). The first row of waste pipes (19) is connected to the first guide groove (22), the second row of waste pipes (20) is connected to the second guide groove (23), and the third row of waste pipes (21) is connected to the bottom of the cleaning chamber (33).

3. A wafer cleaning unit according to claim 2, characterized in that: The servo electric cylinder (17) is fixedly installed at the bottom of the modular cleanroom (1). The telescopic end of the servo electric cylinder (17) is fixedly installed with an air sleeve (24) through a bracket. The upper end of the air sleeve (24) is fixedly installed with a transmission sleeve (25). The transmission sleeve (25) slides through the bottom of the modular cleanroom (1) and extends into the connecting cylinder (3). The top end of the transmission sleeve (25) is fixedly connected to the adapter plate (4).

4. A wafer cleaning unit according to claim 3, characterized in that: The air sleeve (24) is rotatably mounted with a drive shaft (26) through a mechanical seal. The top end of the drive shaft (26) is fixedly connected to the drive seat (5). The servo motor (18) is fixedly mounted at the bottom of the air sleeve (24), and the rotating end of the servo motor (18) is fixedly connected to the bottom end of the drive shaft (26).

5. A wafer cleaning unit according to claim 4, characterized in that: The drive shaft (26) has a transfer air chamber (27) inside. The surface of the drive shaft (26) has multiple through holes (29) that communicate with the transfer air chamber (27). A pumping pipe (28) is fixedly installed on the surface of the air sleeve (24). The pumping pipe (28) communicates with the transfer air chamber (27) through the through holes (29). A connecting hose (30) is provided inside the drive shaft (26). The transfer air chamber (27) communicates with the negative pressure hole (34) through the connecting hose (30).

6. A wafer cleaning unit according to claim 5, characterized in that: The servo electric cylinder (17) drives the adapter plate (4) and the transmission seat (5) to move up and down synchronously to adjust the height. When the adapter plate (4) is higher than the first guide groove (22), the passage between the upper chamber of the connecting cylinder (3) and the first guide groove (22) and the second guide groove (23) is blocked by the adapter plate (4). When the adapter plate (4) is located between the first guide groove (22) and the second guide groove (23), the upper chamber of the connecting cylinder (3) is connected to the first guide groove (22), and the passage between the upper chamber of the connecting cylinder (3) and the second guide groove (23) is blocked by the adapter plate (4).

7. A wafer cleaning unit according to claim 1, characterized in that: The modular cleanroom (1) is rotatably installed with a mechanical swing arm (31), and a multi-channel nozzle (2) is fixedly connected to the mechanical swing arm (31). The mechanical swing arm (31) is equipped with an N2 air curtain nozzle (32) and an IPA steam knife nozzle.

8. A wafer cleaning device, characterized in that: Includes one or more wafer cleaning units as described in any one of claims 1-7, wherein when multiple wafer cleaning units are used, adjacent modular cleanrooms (1) are connected in parallel to form an integrated device.

9. A wafer cleaning method, applied in the wafer cleaning equipment as described in claim 8, characterized in that, Includes the following steps: S1. Loading and pre-rinsing: DI spray for 30–60 seconds, prioritizing DI degassing; S2, SC-1: Spray liquid at 70–80℃, dual-frequency ultrasonic transducer (14) provides dual-frequency sound field, outer ring 0.4 W / cm², inner ring 0.1 W / cm², support platform (8) rotates to 50-100rpm, ±8° swing vibration, remove particles; S3, Rinse: High flow rate DI until ORP and conductivity reach the threshold; S4, SC-2: Spray liquid at 25–40℃, dual-frequency ultrasonic transducer (14) provides low-power sound field, N2 air curtain nozzle (32) edge sweeping bubble, improve metal ion complexation and removal; S5, Rinse and optional HF light treatment: 0.1–0.5% HF for 15–30 s to remove thin oxide / metal hydroxide, followed by full DI replacement; S6. Drying: Use N2 air curtain nozzle (32) for edge drying, use IPA steam knife nozzle for full-area drying, and accelerate the rotation of the support table (8) to 600–800 rpm. S7, Unloading and Transfer.

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