A multi-angle micro-nano bubble cleaning system and method for wafers

Abstract

The present invention discloses a multi-angle micro-nano bubble cleaning system for wafers, belonging to the field of micro-nano bubble cleaning technology, comprising an ozone generator, a heating pool, a micro-nano bubble generator, a cleaning pool, a filter, and an electric control cabinet; the ozone generator and the heating pool are respectively connected to the inlet of the micro-nano bubble generator, the outlet of the micro-nano bubble generator is connected to the inlet of the cleaning pool, and the outlet of the cleaning pool is connected to the filter; the electric control cabinet is electrically connected to the heating pool, the ozone generator, and the micro-nano bubble generator; the cleaning pool includes a cleaning station and a plurality of cleaning nozzles, which can be driven to swing by a reciprocating motor; the present invention also discloses a corresponding cleaning method. The present invention can improve the cleaning efficiency and removal rate of stains on the surface of the wafer, avoid uneven cleaning, and reduce pollution to the environment.

Description

Technical Field

[0001] The present invention belongs to the technical field of micro-nano bubble cleaning, and in particular relates to a multi-angle micro-nano bubble cleaning system and method for wafers. Background Art

[0002] Solar power generation has achieved rapid development in my country. The production process of solar wafers usually involves wafer cleaning to remove particles, metal ions and organic matter remaining on the surface of the wafers during cutting, grinding, polishing and other processes to facilitate subsequent processing and production.

[0003] Currently, commonly used wafer cleaning methods include wet chemical cleaning, ultrasonic cleaning, and vapor-phase dry cleaning. Wet chemical cleaning has a high removal rate, but the process requires a large amount of chemical reagents, which is harmful to the environment. It also increases the surface roughness of the silicon wafer, affecting the surface quality of the wafer. Ultrasonic cleaning is based on the ultrasonic cavitation effect, radiation pressure, and acoustic flow. Ultrasonic cleaning is effective for cleaning large particles, but as the particle size decreases, the cleaning effect decreases. Vapor-phase dry cleaning involves first rotating the product at a low speed and then increasing the speed to dry it. This process effectively removes oxide film contamination through HF vapor, and this method can effectively clean deep structures (such as grooves), but it cannot effectively remove metal contamination. Therefore, none of the above cleaning methods in the existing technology are suitable for wafer cleaning. Summary of the Invention

[0004] In response to one or more of the above-mentioned defects or improvement needs of the prior art, the present invention provides a multi-angle micro-nano bubble cleaning system and method for wafers, which can improve the cleaning efficiency and removal rate of stains on the wafer surface, avoid uneven cleaning, and reduce pollution to the environment.

[0005] To achieve the above objectives, according to one aspect of the present invention, a multi-angle micro-nano bubble cleaning system for wafers is provided, comprising an ozone generator, a heating tank, a micro-nano bubble generator, a cleaning tank, a filter, and an electrical control cabinet;

[0006] The ozone generator and the heating pool are respectively connected to the inlet of the micro-nano bubble generator, the outlet of the micro-nano bubble generator is connected to the inlet of the cleaning pool, and the outlet of the cleaning pool is connected to the filter; the electric control cabinet is electrically connected to the heating pool, the ozone generator, and the micro-nano bubble generator;

[0007] The cleaning pool includes a cleaning station and several cleaning nozzles; the cleaning station is used to place chips, and the cleaning nozzles are located below the chips in the cleaning station; the lower end of each cleaning nozzle is hinged to the auxiliary mounting structure above the bottom of the cleaning pool through a pin; the upper ends of the cleaning nozzles are connected in parallel through a long rod, and the upper ends of the cleaning nozzles are rotatably connected to the long rod; one end of the long rod is connected to a reciprocating motor to drive the long rod to move back and forth, thereby driving the cleaning nozzles to swing.

[0008] As a further improvement of the present invention, the cleaning pool further comprises a cleaning pool nozzle inlet, and the cleaning pool nozzle inlet is connected to each cleaning nozzle;

[0009] The cleaning pool nozzle inlet is connected to the outlet of the micro-nano bubble generator, or the cleaning pool nozzle inlet is connected to the outlets of the ozone generator, the heating pool and the micro-nano bubble generator respectively through a four-way valve.

[0010] As a further improvement of the present invention, the cleaning pool further includes a quick water injection port, which is connected to the outlet of the micro-nano bubble generator; and / or,

[0011] A temperature sensor and a cleaning pool liquid level sensor are also provided in the cleaning pool, and the temperature sensor and the cleaning pool liquid level sensor are electrically connected to the electric control cabinet.

[0012] As a further improvement of the present invention, the cleaning station includes a bottom serrated plate and a side serrated plate, the bottom serrated plate is arranged above the bottom of the cleaning tank through an auxiliary connecting structure, and the side serrated plate is arranged on the side wall of the cleaning tank;

[0013] The bottom serrated plate is located on both sides of the cleaning nozzle, and the top surface height of the bottom serrated plate is higher than the top surface height of the cleaning nozzle;

[0014] The teeth of the bottom serrated plate face upward, and the teeth of the side serrated plate face the inside of the cleaning tank, and the teeth of the bottom serrated plate and the side serrated plate in the same vertical plane correspond to each other one by one, forming a plurality of placement slots for placing wafers in sequence.

[0015] As a further improvement of the present invention, a through hole is provided at the lower end of the cleaning nozzle, a pin passes through the through hole and is fixed by a cotter pin, and the pin is hinged in a U-shaped slot of the mounting plate;

[0016] Keyways are provided on opposite sides of the upper end of the cleaning nozzle, and the two long rods are rotated by cooperating with the keyways through cylindrical rollers arranged on the sides, and the two ends of the two long rods are connected by bolts to clamp the multiple cleaning nozzles.

[0017] As a further improvement of the present invention, a nozzle is provided at the end of the cleaning nozzle, and the end of the nozzle has a hemispherical water outlet; a water pipe is provided inside the nozzle, and the water pipe includes a square hole and a frustum, the square hole is connected to the internal flow channel of the cleaning nozzle, and the frustum is connected to the water outlet.

[0018] As a further improvement of the present invention, the heating pool is provided with a heater, a heating pool liquid level sensor, a water source inlet, and a heating water outlet; the heater and the heating pool liquid level sensor are arranged inside the heating pool, the water source inlet is connected to the external water source through a water source solenoid valve, and the heating water outlet is connected to the micro-nano bubble generator through a circulation pump.

[0019] As a further improvement of the present invention, the ozone generator is provided with an oxygen inlet and an ozone outlet, the oxygen inlet is connected to the oxygen source through an oxygen source solenoid valve, and the ozone outlet is connected to the micro-nano bubble generator; the ozone generator is also provided with a cooling water inlet and a cooling water outlet, which are respectively connected to the inlet and outlet of the water cooler.

[0020] As a further improvement of the present invention, the filter is provided with a sewage inlet, a drain outlet, and a filtered water outlet; the sewage inlet is connected to the outlet of the cleaning pool, the filtered water outlet is connected to the inlet of the heating pool, and the drain outlet is connected to the sewage tank or directly discharged.

[0021] According to another aspect of the present invention, a micro-nano bubble cleaning method for wafers is provided, which is implemented using the multi-angle micro-nano bubble cleaning system, and includes the following steps:

[0022] Oxygen with a concentration of 93-95% is introduced into the ozone generator to produce ozone gas with a concentration of 150-200 ppm, which is then introduced into the micro-nano bubble generator. At the same time, heated water at 35-38°C from the heating pool is introduced into the micro-nano bubble generator. The ozone gas and heated water are mixed in a gas-liquid ratio of 1:15-1:12 to produce micro-nano ozone water.

[0023] Place the wafer in the cleaning tank, inject micro-nano ozone water into the nozzle inlet of the cleaning tank at a flow rate of 13L / min, and spray the micro-nano ozone water in a cyclic swing for 5-6 minutes before closing the cleaning nozzle;

[0024] Open the quick water injection port and inject the micro-nano ozone water at a flow rate of 50L / min for 5-6 minutes, then close the water injection port and let it soak for 5-6 minutes to further remove the stains that have not fallen off, and at the same time let the fallen stains settle at the bottom of the cleaning tank and then drain to the filter;

[0025] Inject heated water into the cleaning tank nozzle inlet at a flow rate of 13L / min, open the cleaning nozzle and intermittently rinse the wafer surface from top to bottom for 10-12 minutes, and then drain the wastewater into the filter;

[0026] The cleaning nozzle sprays ozone gas into the cleaning tank in a cyclic swing to remove organic residue on the surface and dry the wafer, completing the wafer cleaning.

[0027] In general, the above technical solutions conceived by the present invention have the following beneficial effects compared with the prior art:

[0028] (1) The multi-angle micro-nano bubble cleaning system for wafers of the present invention adopts a cleaning scheme of ozone plus micro-nano bubbles. Ozone has a very short half-life, so it can effectively clean organic debris and metal dust on the wafers; the micro-nano bubbles are small in size, large in specific surface area, slow in rising speed, long in residence time, and high in gas dissolution rate, so that they can dissolve more ozone and fully contact the wafer surface, thereby improving the stain removal rate and removal efficiency.

[0029] (2) The multi-angle micro-nano bubble cleaning system for wafers of the present invention places the temperature sensor in the cleaning tank and the heating device in the heating tank in front of the micro-nano bubble generator, which ensures that the cleaning temperature is within a controllable range and avoids the generation of micro-nano bubbles first and then heating to cause the bubble volume to grow, reduce the amount of gas dissolved, and reduce the stain removal rate.

[0030] (3) The multi-angle micro-nano bubble cleaning system for wafers of the present invention has a cleaning tank nozzle inlet connected to an ozone generator, a heating tank, and a micro-nano bubble generator, respectively. Not only can micro-nano ozone water be introduced into the cleaning tank nozzle inlet for cleaning, but also heating water in the heating tank can be introduced to rinse the wafers, and ozone gas from the ozone generator can be introduced to dry the wafers.

[0031] (4) The multi-angle micro-nano bubble cleaning system for wafers of the present invention uses a reciprocating motor to realize the left and right swing of the nozzle, so that the micro-nano ozone water can directly contact the wafer from top to bottom, avoiding uneven cleaning.

[0032] (5) The multi-angle micro-nano bubble cleaning system for wafers of the present invention can not only stably support the bottom and sides of the wafer through the cooperation of the bottom serrated plate and the side serrated plate of the cleaning station, but also minimize the obstruction of the water flow by the cleaning station, thereby avoiding the situation where local cleaning is not in place.

[0033] (6) The multi-angle micro-nano bubble cleaning system for wafers of the present invention adopts a cleaning nozzle with a hemispherical water outlet, which increases the speed at which the micro-nano ozone water flow reaches the wafer and increases the contact area between the water flow and the wafer, thereby avoiding uneven cleaning.

[0034] (7) The multi-angle micro-nano bubble cleaning method for wafers of the present invention adopts staged cleaning. One cleaning cycle consumes about 0.5 tons of water and takes about 30 minutes. Compared with wet chemical cleaning, there is no need to remove residual chemical solution and no need for long-term soaking, which reduces water consumption and cleaning time and improves the removal efficiency of particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is a schematic diagram of the overall structure of a multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention;

[0036] Figure 2 Schematic diagram of the cleaning pool structure involved in the multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention;

[0037] Figure 3 A cross-sectional view of a cleaning pool involved in a multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention;

[0038] Figure 4 Schematic diagram of the toothed plate structure involved in the cleaning pool of an embodiment of the present invention;

[0039] Figure 5 This is a schematic diagram of the assembly structure of a cleaning nozzle involved in a cleaning pool according to an embodiment of the present invention;

[0040] Figure 6 Schematic diagram of the cleaning nozzle structure involved in the cleaning pool of an embodiment of the present invention;

[0041] Figure 7 Schematic diagram of the nozzle structure involved in the cleaning pool of an embodiment of the present invention;

[0042] Figure 8 This is a control logic diagram of a multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention.

[0043] In all the drawings, the same reference numerals represent the same technical features, specifically: 1. Electric control cabinet; 2. Water chiller; 3. Ozone generator; 4. Heating tank; 5. Circulation pump; 6. Micro-nano bubble generator; 7. Cleaning tank; 8. Filter; 9. PLC controller; 10. HMI touch screen; 11. Temperature sensor; 12. Cleaning tank level sensor; 13. Heater; 14. Heating tank level sensor; 15. Water source solenoid valve; 16. Oxygen source solenoid valve; 17. Oxygen inlet; 18. Ozone outlet; 19. Cooling water inlet; 20. Cooling water outlet; 2 1. Ozone inlet; 22. Heating water inlet; 23. Micro-nano ozone water outlet; 24. Heating water outlet; 25. Cleaning pool nozzle inlet; 26. Quick water injection port; 27. Cleaning tank; 28. Cleaning nozzle; 29. ​​Cleaning station; 30. Sewage outlet; 31. Sewage inlet; 32. Serrated plate; 33. Chip; 34. Drain outlet; 35. Filtered water outlet; 36. Circulating water inlet; 37. Water source inlet; 38. Pin; 39. Long rod; 40. Cylindrical roller; 41. Keyway; 42. Bolt; 43. Reciprocating motor; 44. Cleaning liquid inlet; 45. Nozzle. DETAILED DESCRIPTION

[0044] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only intended to illustrate the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0045] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referred to. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

[0047] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection; direct connection, or indirect connection through an intermediate medium; internal communication between two components, or interaction between two components, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0048] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0049] As a preferred embodiment of the present invention, Figures 1 to 7 As shown, the multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention includes an electrical control cabinet 1, a water chiller 2, an ozone generator 3, a heating tank 4, a micro-nano bubble generator 6, a cleaning tank 7, and a filter 8. The ozone generator 3 and the heating tank 4 are respectively connected to the inlet of the micro-nano bubble generator 6, the outlet of the micro-nano bubble generator 6 is connected to the inlet of the cleaning tank 7, and the outlet of the cleaning tank 7 is connected to the filter 8. The electrical control cabinet 1 is electrically connected to the heating tank 4, the micro-nano bubble generator 6, and the temperature sensor 11.

[0050] In the preferred embodiment, see Figure 1 The ozone generator 3 is equipped with an oxygen inlet 17 and an ozone outlet 18. The oxygen inlet 17 is connected to the oxygen source via an oxygen source solenoid valve 16, and the ozone outlet 18 is connected to the micro-nano bubble generator 6. The oxygen source solenoid valve 16 is electrically connected to the electrical control cabinet 1. The ozone generator 3 is also equipped with a cooling water inlet 19 and a cooling water outlet 20, which are respectively connected to the inlet and outlet of the water chiller 2.

[0051] Oxygen with a concentration of 93-95% enters the ozone generator 3 through the oxygen source solenoid valve 16, and is dried and discharged at high voltage on the ceramic plate. O 2 molecules dissociate and collide to form O 3. Ozone gas is introduced into the micro-nano bubble generator 6 from the ozone outlet 18. Since the machine generates a lot of heat during the ozone generation process, the embodiment of the present invention connects the water cooler 2 to the ozone generator 3 to cool it.

[0052] In the preferred embodiment, see Figure 1 The heating pool 4 is provided with a heater 13, a heating pool liquid level sensor 14, a water source inlet 37, and a heated water outlet 24. The heater 13 and the heating pool liquid level sensor 14 are located inside the heating pool 4, with the heater 13 preferably located in the middle of the heating pool 4 and the heating pool liquid level sensor 14 preferably located on the side of the heating pool 4. The water source inlet 37 is connected to the external water source via a water source solenoid valve 15, and the heated water outlet 24 is connected to the micro-nano bubble generator 6 via a circulation pump 5. The water source solenoid valve 15 is electrically connected to the electric control cabinet 1. The heating pool 4 is also provided with a circulating water inlet 36, which is connected to the filter 8.

[0053] In the preferred embodiment, see Figure 1 The micro-nano bubble generator 6 is equipped with an ozone inlet 21, a heating water inlet 22, and a micro-nano ozone water outlet 23. The ozone inlet 21 is connected to the ozone outlet 18 of the ozone generator 3, the heating water inlet 22 is connected to the heating water outlet 24 of the heating tank 4 via the circulation pump 5, and the micro-nano ozone water outlet 23 is connected to the cleaning tank 7. Ozone and heating water enter the micro-nano bubble generator 6 through the ozone inlet 21 and the heating water inlet 22, respectively. A micro-nano ozone aqueous solution is produced through gas-liquid shearing, high-pressure dissolution, and low-pressure release, and then passed into the cleaning tank 7 through the micro-nano ozone water outlet 23.

[0054] In the preferred embodiment, see Figure 2 The cleaning tank 7 includes a cleaning tank 27, a cleaning tank nozzle inlet 25, a cleaning nozzle 28, a cleaning station 29, and a sewage outlet 30. The cleaning nozzle 28 and the cleaning station 29 are both arranged above the bottom plate of the cleaning tank 27 at a certain distance from the bottom plate to avoid affecting the discharge of sewage; the cleaning station 29 is used to place wafers, and the cleaning nozzle 28 is located below the wafers placed on the cleaning station 29. The cleaning nozzle 28 is preferably set at a position 20 mm away from the bottom plate of the cleaning tank 27; the sewage outlet 30 is set at the bottom of the cleaning tank 27, which is connected to the filter 8. The cleaning tank nozzle inlet 25 is connected to the micro-nano ozone water outlet 23 of the micro-nano bubble generator 6, and the cleaning tank nozzle inlet 25 is connected to several cleaning nozzles 28. Combined Figure 6 As shown, a cleaning liquid inlet 44 is provided on the side of each cleaning nozzle 28 , and each cleaning liquid inlet 44 is simultaneously connected to the cleaning tank nozzle inlet 25 through a connecting main pipe, so that the cleaning liquid is sprayed out from the cleaning nozzle 28 at the same time.

[0055] See again Figure 1The cleaning pool 7 also includes a quick water injection port 26, which is connected to the micro-nano ozone water outlet 23 of the micro-nano bubble generator 6 via a solenoid valve, enabling rapid injection of micro-nano ozone water for soaking the wafers 33. A cleaning pool liquid level sensor 12 is also provided within the cleaning pool 7. The cleaning pool liquid level sensor 12 is electrically connected to the electrical control cabinet 1 and is used to monitor the liquid level during water injection at the quick water injection port 26. A temperature sensor 11 is also provided within the cleaning pool 7 and is electrically connected to the electrical control cabinet 1 and is used to monitor the temperature of the micro-nano ozone water within the cleaning pool 7.

[0056] Combine Figures 2 to 4 The cleaning station 29 includes a plurality of serrated plates 32, specifically a bottom serrated plate and a side serrated plate, wherein the bottom serrated plate is arranged above the bottom plate of the cleaning tank 27 through an auxiliary connection structure, and the bottom serrated plate is located on both sides of the cleaning nozzle 28, and the top surface height of the bottom serrated plate is higher than the top surface height of the cleaning nozzle 28, so that when the wafer 33 is placed on the bottom serrated plate, the cleaning nozzle 28 is located a certain distance below the wafer 33; the side serrated plates are arranged on the side plates of the cleaning tank 27 (preferably 250mm away from the bottom plate of the cleaning tank 27). One side of the serrated plate 32 is serrated, with the serrated teeth of the bottom serrated plate facing upwards and the serrated teeth of the side serrated plates facing the inside of the cleaning tank 27, and the serrated teeth of the bottom serrated plate and the side serrated plates correspond one to one in the same vertical plane, forming a plurality of placement slots in sequence, and the wafer 33 can be stuck in the corresponding placement slot, and its bottom and sides are stably supported by the bottom serrated plate and the side serrated plates. At the same time, the present invention can minimize the obstruction of the cleaning station 29 to the water flow through the cooperation of the bottom serrated plate, the side serrated plate and the cleaning nozzle 28, thereby avoiding the situation where local cleaning is not in place.

[0057] Further preferably, in order to make the micro-nano ozone water fully contact with the wafer 33 and avoid uneven cleaning, the cleaning nozzle 28 in the embodiment of the present invention is swung by a reciprocating motor 43. Figure 5 and Figure 6As shown, the lower end of each cleaning nozzle 28 is hinged to an auxiliary connecting structure (such as a mounting bracket) above the bottom plate of the cleaning tank 27 via a pin 38. Specifically, the lower end of the cleaning nozzle 28 is provided with a through hole, through which the pin 38 passes and is secured by a cotter pin. The pin 38 is also hinged within a U-shaped slot in the mounting bracket above the bottom plate of the cleaning tank 27. The upper ends of the cleaning nozzles 28 are connected in parallel via a long rod 39, and the upper ends of the cleaning nozzles 28 are rotatably connected to the long rod 39. Specifically, key slots 41 are provided on opposite sides of the upper ends of the cleaning nozzles 28. The two long rods 39 are rotated by cylindrical rollers 40 provided on the sides and engaging corresponding key slots 41. The two ends of the two long rods 39 are connected by bolts 42 to clamp the multiple cleaning nozzles 28. One end of the long rod 39 is connected to the reciprocating motor 43 to drive the long rod 39 to move back and forth, thereby driving the cylindrical roller 40 on the long rod 39 to slide in the key groove 41, and then driving the cleaning nozzle 28 to swing along the placement direction of the chip 33 (longitudinal direction of the cleaning station).

[0058] More preferably, see Figure 7 The end of the cleaning nozzle 28 is provided with a nozzle 45, which is preferably threaded and mounted thereto for easy periodic replacement. The end of the nozzle 45 has a hemispherical outlet with a horizontal opening angle of 160° and a vertical opening angle of 20°. A water pipe is located within the nozzle 45. The pipe comprises a square hole and a frustum. The square hole communicates with the flow channel within the cleaning nozzle 28, while the frustum connects to the outlet, ensuring more uniform water distribution and reducing erosion on the nozzle.

[0059] During cleaning, wafers 33 are placed sequentially on cleaning stations 29. Micro-nano ozone water enters the cleaning tank through nozzle inlet 25. Driven by a reciprocating motor 43, the micro-nano ozone water is sprayed at different angles through cleaning nozzles 28 onto the surface of wafers 33, achieving multi-angle cleaning. After cleaning, the wastewater containing impurities flows out through wastewater outlet 30. In practice, after 15 minutes of cleaning, the stain removal rate on the wafer surface can reach 95%.

[0060] Further preferably, the cleaning tank nozzle inlet 25 is connected to the ozone outlet 18 of the ozone generator 3, the heated water outlet 24 of the heating tank 4, and the micro-nano ozone water outlet 23 of the micro-nano bubble generator 6 through a four-way valve, and each of the above-mentioned connecting pipes is preferably provided with a solenoid valve, and the corresponding solenoid valve controls the opening and closing of the corresponding pipe. Through this arrangement, not only can micro-nano ozone water be introduced into the cleaning tank nozzle inlet 25 to clean the wafer 33, but also heated water in the heating tank 4 can be introduced to rinse the wafer 33, or ozone gas from the ozone generator 3 can be introduced to dry the wafer 33.

[0061] In a preferred embodiment, filter 8 is equipped with a sewage inlet 31, a drain outlet 34, and a filtered water outlet 35. The sewage inlet 31 is connected to the sewage outlet 30 of the cleaning tank 7, and the filtered water outlet 35 is connected to the circulating water inlet 36 of the heating tank 4. The circulating water discharged from filter 8 enters the heating tank 4. Sewage enters filter 8 through sewage inlet 31 of filter 8, is filtered by the filter membrane, and the filtered circulating water is discharged from filtered water outlet 35 and enters the heating tank 4 through the circulating water inlet 36 of the heating tank 4. Drain outlet 34 is connected to a sewage tank or directly discharged, and the sewage filtered by filter 8 flows out of drain outlet 34.

[0062] In a preferred embodiment, the electric control cabinet 1 is provided with a PLC controller 9 and an HMI touch screen 10, wherein the HMI touch screen 10 is installed on the door panel of the electric control cabinet 1, and the PLC controller 9 and the HMI touch screen 10 are connected via a PROFITNET interface, and the control parameters of the PLC controller 9 can be monitored and adjusted on the HMI touch screen 10.

[0063] More preferably, Figure 8 As shown, the PLC controller 9 is electrically connected to the temperature sensor 11 in the cleaning pool 7, the cleaning pool liquid level sensor 12, the heating pool liquid level sensor 14 in the heating pool 4, the water source solenoid valve 15, and the oxygen source solenoid valve 16 through the IO port.

[0064] The input port of the PLC controller 9 is connected to a temperature sensor 11 for measuring the temperature of the micro-nano ozone water in the cleaning pool 7, and the temperature signal is fed back to the PLC controller 9. The PLC controller 9 controls the operation of the heater 13 in the heating pool 4 to maintain the temperature of the micro-nano ozone water reaching the cleaning pool 7 between 35 and 38°C; the PLC controller 9 is connected to the heating pool liquid level sensor 14, the water source solenoid valve 15, and the cleaning pool liquid level sensor 12. When the heating pool liquid level sensor 14 detects that the water level in the heating pool 4 is low, the water source solenoid valve 15 is opened to inject water into the heating pool 4; when the cleaning pool liquid level sensor 12 detects that the liquid level in the cleaning pool 7 is low, the flow rate of the micro-nano bubble generator 6 is increased.

[0065] More preferably, Figure 8 As shown, the PLC controller 9 is electrically connected to the ozone generator 3, the micro-nano bubble generator 6, and the heater 13 via an RS485 communication port. The RS485 communication port of the PLC controller 9 is connected to the controllers of the ozone generator 3 and the micro-nano bubble generator 6 for adjusting the operating parameters of the ozone generator 3 and the micro-nano bubble generator 6; the PLC controller 9 is connected to the controller of the heater 13 for controlling the operating parameters of the heater 13.

[0066] The multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention provides a preferred cleaning process as follows:

[0067] Oxygen with a concentration of 93-95% is introduced into the ozone generator 3 to generate ozone gas with a concentration of 150-200 ppm, which is then introduced into the micro-nano bubble generator 6. At the same time, heated water at 35-38°C from the heating pool 4 is introduced into the micro-nano bubble generator 6. The ozone gas and heated water are mixed in a gas-liquid ratio of 1:15-1:12 to produce micro-nano ozone water.

[0068] During the cleaning process, the wafer 33 is first placed in the cleaning tank 7, and micro-nano ozone water is injected into the cleaning tank nozzle inlet 25 at a flow rate of 13L / min. The micro-nano ozone water is sprayed in a cyclic swing for 5-6 minutes, and then the cleaning nozzle 28 is closed;

[0069] Open the quick water injection port 26 and inject the micro-nano ozone water at a flow rate of 50L / min for 5-6 minutes, then close the water injection port and let it soak for 5-6 minutes to further remove the unremoved stains and allow the removed stains to settle at the bottom of the cleaning tank 7 and then drain to the filter 8;

[0070] Then, the heated water in the heating tank 4 is injected into the cleaning tank nozzle inlet 25 at a flow rate of 13 L / min, the cleaning nozzle 28 is turned on, and the surface of the wafer 33 is intermittently rinsed from top to bottom for 10 to 12 minutes, and then the waste water is discharged to the filter 8;

[0071] Then the cleaning nozzle 28 circulates and swings to spray ozone gas from the ozone generator 3 into the cleaning tank; on the one hand, it further removes residual organic matter on the surface, and on the other hand, it dries the wafer 33. At this point, the cleaned wafer is taken out to complete a working cycle.

[0072] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A multi-angle micro-nano bubble cleaning system for wafers, characterized in that: Including ozone generator, heating pool, micro-nano bubble generator, cleaning pool, filter and electric control cabinet; The ozone generator and the heating pool are respectively connected to the inlet of the micro-nano bubble generator. The heating pool is provided with a heated water outlet, which is connected to the micro-nano bubble generator through a circulation pump. The cleaning pool includes a cleaning pool nozzle inlet, which is respectively connected to the outlets of the ozone generator, the heating pool, and the micro-nano bubble generator through a four-way valve. The outlet of the cleaning pool is connected to the filter. The electric control cabinet is electrically connected to the heating pool, the ozone generator, and the micro-nano bubble generator. The cleaning pool also includes a quick water injection port, which is connected to the outlet of the micro-nano bubble generator. The cleaning tank also includes a cleaning station and several cleaning nozzles; the cleaning station is used to place chips, and the cleaning nozzles are located below the chips in the cleaning station; the lower end of each cleaning nozzle is hinged to an auxiliary mounting structure above the bottom of the cleaning tank through a pin; the upper ends of the cleaning nozzles are connected in parallel through a long rod, and the upper ends of the cleaning nozzles are rotatably connected to the long rod; one end of the long rod is connected to a reciprocating motor to drive the long rod to move back and forth, thereby driving the cleaning nozzles to swing.

2. The multi-angle micro-nano bubble cleaning system for wafers according to claim 1, characterized in that: The cleaning pool nozzle inlet is connected to each cleaning nozzle.

3. The multi-angle micro-nano bubble cleaning system for wafers according to claim 1, characterized in that: A temperature sensor and a cleaning pool liquid level sensor are also provided in the cleaning pool, and the temperature sensor and the cleaning pool liquid level sensor are electrically connected to the electric control cabinet.

4. The multi-angle micro-nano bubble cleaning system for wafers according to claim 1, characterized in that: The cleaning station includes a bottom serrated plate and a side serrated plate, wherein the bottom serrated plate is arranged above the bottom of the cleaning tank through an auxiliary connection structure, and the side serrated plate is arranged on the side wall of the cleaning tank; The bottom serrated plate is located on both sides of the cleaning nozzle, and the top surface height of the bottom serrated plate is higher than the top surface height of the cleaning nozzle; The teeth of the bottom serrated plate face upward, and the teeth of the side serrated plate face the inside of the cleaning tank, and the teeth of the bottom serrated plate and the side serrated plate in the same vertical plane correspond to each other one by one, forming a plurality of placement slots for placing wafers in sequence.

5. The multi-angle micro-nano bubble cleaning system for wafers according to any one of claims 1 to 4, characterized in that: A through hole is provided at the lower end of the cleaning nozzle, through which a pin passes and is fixed by a cotter pin, while the pin is hinged in a U-shaped slot of the mounting plate; Keyways are provided on opposite sides of the upper end of the cleaning nozzle, and the two long rods are rotated by cooperating with the keyways through cylindrical rollers arranged on the sides, and the two ends of the two long rods are connected by bolts to clamp the multiple cleaning nozzles.

6. The multi-angle micro-nano bubble cleaning system for wafers according to any one of claims 1 to 4, characterized in that: A nozzle is provided at the end of the cleaning nozzle, and the end of the nozzle has a hemispherical water outlet; a water pipe is provided inside the nozzle, and the water pipe includes a square hole and a frustum, the square hole is connected to the internal flow channel of the cleaning nozzle, and the frustum is connected to the water outlet.

7. The multi-angle micro-nano bubble cleaning system for wafers according to any one of claims 1 to 4, characterized in that: The heating pool is also provided with a heater, a heating pool liquid level sensor, and a water source inlet; the heater and the heating pool liquid level sensor are arranged inside the heating pool, and the water source inlet is connected to an external water source through a water source solenoid valve.

8. The multi-angle micro-nano bubble cleaning system for wafers according to any one of claims 1 to 4, characterized in that: The ozone generator is provided with an oxygen inlet and an ozone outlet. The oxygen inlet is connected to the oxygen source through an oxygen source solenoid valve, and the ozone outlet is connected to the micro-nano bubble generator. The ozone generator is also provided with a cooling water inlet and a cooling water outlet, which are respectively connected to the inlet and outlet of the water cooler.

9. The multi-angle micro-nano bubble cleaning system for wafers according to any one of claims 1 to 4, characterized in that: The filter is provided with a sewage inlet, a drain outlet and a filtered water outlet; the sewage inlet is connected to the outlet of the cleaning pool, the filtered water outlet is connected to the inlet of the heating pool, and the drain outlet is connected to the sewage tank or directly discharged.

10. A micro-nano bubble cleaning method for wafers, implemented using the multi-angle micro-nano bubble cleaning system according to any one of claims 1 to 9, characterized in that: The steps include: Oxygen with a concentration of 93-95% is introduced into the ozone generator to produce ozone gas with a concentration of 150-200 ppm, which is then introduced into the micro-nano bubble generator. At the same time, heated water at 35-38°C from the heating pool is introduced into the micro-nano bubble generator. The ozone gas and heated water are mixed in a gas-liquid ratio of 1:15-1:12 to produce micro-nano ozone water. Place the wafer in the cleaning tank, inject micro-nano ozone water into the nozzle inlet of the cleaning tank at a flow rate of 13L / min, and spray the micro-nano ozone water in a cyclic swing for 5-6 minutes before closing the cleaning nozzle; Open the quick water injection port and inject the micro-nano ozone water at a flow rate of 50L / min for 5-6 minutes, then close the water injection port and let it soak for 5-6 minutes to further remove the stains that have not fallen off, and at the same time let the fallen stains settle at the bottom of the cleaning tank and then drain to the filter; Inject heated water into the cleaning tank nozzle inlet at a flow rate of 13L / min, open the cleaning nozzle and intermittently rinse the wafer surface for 10-12 minutes, and then drain the wastewater into the filter; The cleaning nozzle sprays ozone gas into the cleaning tank in a cyclic swing to remove organic residue on the surface and dry the wafer, completing the wafer cleaning.

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