Multi-angle micro-nano bubble cleaning system and method for wafer

Abstract

The invention discloses a multi-angle micro-nano bubble cleaning system for wafers, which belongs to the technical field of micro-nano bubble cleaning and comprises an ozone generator, a heating tank, a micro-nano bubble generator, a cleaning tank, a filter and an electric control cabinet. The ozone generator and the heating tank are respectively connected with an inlet of the micro-nano bubble generator, an outlet of the micro-nano bubble generator is connected with an inlet of the cleaning tank, and an outlet of the cleaning tank is connected with the filter; the electric control cabinet is electrically connected with the heating tank, the ozone generator and the micro-nano bubble generator; the cleaning pool comprises a cleaning station and a plurality of cleaning nozzles, and the cleaning nozzles can be driven to swing through a reciprocating motor; the invention further discloses a corresponding cleaning method. The cleaning efficiency and the removal rate of stains on the surface of the wafer can be improved, uneven cleaning is avoided, and pollution to the environment is reduced.

Description

Technical Field

[0001] The 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] At present, the commonly used wafer cleaning methods include wet chemical cleaning, ultrasonic cleaning, gas phase dry cleaning, etc. Wet chemical cleaning has a high cleaning removal rate, but a large amount of chemical reagents are required in the process, which is harmful to the environment, and it will also increase the surface roughness of the silicon wafer, affecting the surface quality of the wafer; the main principle of ultrasonic cleaning is ultrasonic cavitation effect, radiation pressure and acoustic flow. Ultrasonic cleaning has a significant cleaning effect on large particle pollutants, but as the particle size decreases, the cleaning effect also decreases; gas phase dry cleaning method is to first rotate the product at a low speed, and then increase the speed to rotate the product to dry. In the above process, HF steam can well remove oxide film contamination, and this method can effectively clean the deeper parts of the structure (such as grooves), but this method cannot effectively remove metal pollution. Therefore, the above cleaning methods of the prior art are not suitable for wafer cleaning. Summary of the invention

[0004] In response to one or more of the above defects or improvement needs in 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 object, 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 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; the cleaning station is used to place wafers, and the cleaning nozzles are located below the wafers at the cleaning station; the lower end of each cleaning nozzle is hinged to an auxiliary mounting structure above the bottom of the cleaning pool through a pin shaft; 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.

[0006] 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; 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.

[0007] As a further improvement of the present invention, the cleaning pool further includes a quick water injection port, and the quick water injection port is connected to the outlet of the micro-nano bubble generator; and / or, 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.

[0008] As a further improvement of the present invention, the cleaning station comprises 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 at 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 inner side 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 grooves for placing wafers in sequence.

[0009] As a further improvement of the present invention, a through hole is provided at the lower end of the cleaning nozzle, the 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; Keyways are provided on opposite sides of the upper end of the cleaning nozzle, and two long rods are respectively rotated by cooperating with the keyways through cylindrical rollers arranged on the sides, and the two ends of the two long rods are respectively connected by bolts to clamp multiple cleaning nozzles.

[0010] 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.

[0011] 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 circulating pump.

[0012] 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.

[0013] 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 tank, the filtered water outlet is connected to the inlet of the heating tank, and the drain outlet is connected to the sewage tank or directly discharged.

[0014] According to another aspect of the present invention, a micro-nano bubble cleaning method for a wafer is provided, which is implemented by using the multi-angle micro-nano bubble cleaning system, and comprises the following steps: Oxygen with a concentration of 93-95% is introduced into the ozone generator to generate ozone gas with a concentration of 150-200ppm, which is then introduced into the micro-nano bubble generator; at the same time, the heating water at 35-38℃ in the heating pool is introduced into the micro-nano bubble generator, and the ozone gas and the heating water are mixed in a gas-liquid ratio of 1:15-1:12 to generate 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 circulate and oscillate the micro-nano ozone water 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 from top to bottom for 10-12 minutes, and then drain the waste water to the filter; The cleaning nozzle sprays ozone gas into the cleaning tank in a cyclic swing to remove residual organic matter on the surface and dry the wafer, completing the wafer cleaning.

[0015] In general, the above technical solution conceived by the present invention has the following beneficial effects compared with the prior art: (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. The half-life of ozone is very short, so it can effectively clean organic debris and metal dust on the wafer; 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 to fully contact the wafer surface, thereby improving the stain removal rate and removal efficiency.

[0016] (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 not only ensures that the cleaning temperature is within a controllable range, but also avoids the generation of micro-nano bubbles first and then heating to cause the bubble volume to grow, reduce the gas dissolution amount, and reduce the stain removal rate.

[0017] (3) In the multi-angle micro-nano bubble cleaning system for wafers of the present invention, the nozzle inlet of the cleaning pool is respectively connected to the ozone generator, the heating pool, and the micro-nano bubble generator. Not only can micro-nano ozone water be introduced into the nozzle inlet of the cleaning pool for cleaning, but also the heated water in the heating pool can be introduced to rinse the wafers, and the ozone gas of the ozone generator can be introduced to dry the wafers.

[0018] (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.

[0019] (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 cleaning station to the water flow, thereby avoiding the situation where local cleaning is not in place.

[0020] (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.

[0021] (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 immersion, which reduces water consumption and cleaning time and improves the removal efficiency of particles. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] 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; Figure 2 A schematic diagram of the structure of a cleaning pool involved in a multi-angle micro-nano bubble cleaning system for wafers according to an embodiment of the present invention; 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; Figure 4 It is a schematic diagram of the structure of the toothed plate involved in the cleaning pool of an embodiment of the present invention; Figure 5 It is a schematic diagram of the assembly structure of the cleaning nozzle involved in the cleaning pool of an embodiment of the present invention; Figure 6 It is a schematic diagram of the structure of a cleaning nozzle involved in a cleaning pool according to an embodiment of the present invention; Figure 7 Schematic diagram of the nozzle structure involved in the cleaning pool of an embodiment of the present invention; 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.

[0023] In all the drawings, the same reference numerals represent the same technical features, specifically: 1. electric control cabinet; 2. water cooler; 3. ozone generator; 4. heating pool; 5. circulation pump; 6. micro-nano bubble generator; 7. cleaning pool; 8. filter; 9. PLC controller; 10. HMI touch screen; 11. temperature sensor; 12. cleaning pool level sensor; 13. heater; 14. heating pool 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. Sawtooth plate; 33. Chip; 34. Drain; 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

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain 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 can be combined with each other as long as they do not conflict with each other.

[0025] In the description of the present invention, it is to 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”, etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0026] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0027] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0028] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0029] 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 the embodiment of the present invention comprises an electric control cabinet 1, a water cooler 2, an ozone generator 3, a heating pool 4, a micro-nano bubble generator 6, a cleaning pool 7, and a filter 8. The ozone generator 3 and the heating pool 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 pool 7, and the outlet of the cleaning pool 7 is connected to the filter 8. The electric control cabinet 1 is electrically connected to the heating pool 4, the micro-nano bubble generator 6, and the temperature sensor 11.

[0030] In a preferred embodiment, see Figure 1 The ozone generator 3 is provided with an oxygen inlet 17 and an ozone outlet 18, wherein the oxygen inlet 17 is connected to the oxygen source through 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 electric control cabinet 1. The ozone generator 3 is also provided with a cooling water inlet 19 and a cooling water outlet 20, which are respectively connected to the inlet and outlet of the water cooler 2.

[0031] Oxygen with a concentration of 93-95% enters the ozone generator 3 through the oxygen source solenoid valve 16, and is discharged through the drying and ceramic plate high voltage. O 2 Molecular dissociation and collision O 3, the ozone gas is introduced into the micro-nano bubble generator 6 from the ozone outlet 18. Since the machine generates a large amount 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.

[0032] In a 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 heating water outlet 24. The heater 13 and the heating pool liquid level sensor 14 are arranged inside the heating pool 4, and the heater 13 is preferably arranged in the middle of the heating pool 4, and the heating pool liquid level sensor 14 is preferably arranged on the side of the heating pool 4; the water source inlet 37 is connected to the external water source through the water source solenoid valve 15, and the heating water outlet 24 is connected to the micro-nano bubble generator 6 through the circulating pump 5, and 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, and the circulating water inlet 36 is connected to the filter 8.

[0033] In a preferred embodiment, see Figure 1 The micro-nano bubble generator 6 is provided with an ozone inlet 21, a heating water inlet 22, and a micro-nano ozone water outlet 23; wherein 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 pool 4 through the circulation pump 5, and the micro-nano ozone water outlet 23 is connected to the cleaning pool 7. Ozone and heating water enter the micro-nano bubble generator 6 through the ozone inlet 21 and the heating water inlet 22 respectively, and the micro-nano ozone aqueous solution is obtained through gas-liquid shearing, high-pressure dissolution, and low-pressure release, and then it is passed into the cleaning pool 7 through the micro-nano ozone water outlet 23.

[0034] In a 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 arranged at a position 20 mm away from the bottom plate of the cleaning tank 27; the sewage outlet 30 is arranged 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 a plurality of cleaning nozzles 28. Combined with 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.

[0035] 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 through an electromagnetic valve to achieve quick injection of micro-nano ozone water for soaking the wafer 33. A cleaning pool liquid level sensor 12 is also provided in the cleaning pool 7, and the cleaning pool liquid level sensor 12 is electrically connected to the electric control cabinet 1 to monitor the liquid level when the quick water injection port 26 is injected. A temperature sensor 11 is also provided in the cleaning pool 7, and the temperature sensor 11 is electrically connected to the electric control cabinet 1 to monitor the temperature of the micro-nano ozone water in the cleaning pool 7.

[0036] Combination Figures 2 to 4 The cleaning station 29 includes a plurality of sawtooth plates 32, specifically a bottom sawtooth plate and a side sawtooth plate, wherein the bottom sawtooth plate is arranged above the bottom plate of the cleaning tank 27 through an auxiliary connection structure, and the bottom sawtooth plate is located on both sides of the cleaning nozzle 28, and the top surface height of the bottom sawtooth plate is higher than the top surface height of the cleaning nozzle 28, so that when the wafer 33 is placed on the bottom sawtooth plate, the cleaning nozzle 28 is located at a certain distance directly below the wafer 33; the side sawtooth plate is arranged on the side plate of the cleaning tank 27 (preferably 250mm away from the bottom plate of the cleaning tank 27). One side of the sawtooth plate 32 is sawtoothed, the sawtooth of the bottom sawtooth plate faces upward, the sawtooth of the side sawtooth plate faces the inside of the cleaning tank 27, and the sawtooth of the bottom sawtooth plate and the side sawtooth plate correspond one by one in the same vertical plane, forming a plurality of placement grooves in sequence, the wafer 33 can be stuck in the corresponding placement groove, and the bottom and side of the wafer 33 are stably supported by the bottom sawtooth plate and the side sawtooth plate. At the same time, the present invention can reduce the obstruction of the cleaning station 29 to the water flow as much as possible 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.

[0037] Further preferably, in order to allow the micro-nano ozone water to fully contact 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 the auxiliary connection structure (such as a mounting frame) above the bottom plate of the cleaning tank 27 through a pin 38. Specifically, a through hole is provided at the lower end of the cleaning nozzle 28, and the pin 38 passes through the through hole and is fixed by a split pin. At the same time, the pin 38 is hinged in the U-shaped slot of the mounting frame above the bottom plate of the cleaning tank 27. The upper ends of the cleaning nozzles 28 are connected in parallel through 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 the opposite sides of the upper ends of the cleaning nozzles 28, and the two long rods 39 are respectively rotated by cooperating with the corresponding key slots 41 through cylindrical rollers 40 provided on the side; and the two ends of the two long rods 39 are respectively connected by bolts 42 to clamp the multiple cleaning nozzles 28. One end of the long rod 39 is connected to a 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 slot 41, and then driving the cleaning nozzle 28 to swing along the placement direction of the chip 33 (longitudinal direction of the cleaning station).

[0038] More preferably, see Figure 7 The end of the cleaning nozzle 28 is provided with a nozzle 45, which is preferably installed at the end of the cleaning nozzle 28 by threading, so as to facilitate regular replacement. The end of the nozzle 45 has a hemispherical water outlet, whose horizontal opening angle is 160° and vertical opening angle is 20°; the inside of the nozzle 45 is provided with a water pipe, which includes a square hole and a frustum, the square hole is connected to the internal flow channel of the cleaning nozzle 28, and the frustum is connected to the water outlet, so that the water flow distribution is more uniform and the erosion of the nozzle is reduced.

[0039] During cleaning, the wafers 33 are placed on the cleaning station 29 in sequence, and the micro-nano ozone water enters through the cleaning pool nozzle inlet 25. Under the action of the reciprocating motor 43, the micro-nano ozone water is cyclically sprayed at different angles through the cleaning nozzle 28 to the surface of the wafer 33 to achieve multi-angle cleaning of the wafer. After washing, the sewage with impurities flows out through the sewage outlet 30. In actual application, after 15 minutes of cleaning, the stain removal rate on the wafer surface can reach 95%.

[0040] Further preferably, the cleaning pool nozzle inlet 25 is connected to the ozone outlet 18 of the ozone generator 3, the heating water outlet 24 of the heating pool 4, and the micro-nano ozone water outlet 23 of the micro-nano bubble generator 6 through a four-way valve, and the above-mentioned connecting pipelines are preferably provided with solenoid valves, and the switches of the corresponding pipelines are controlled by the corresponding solenoid valves. Through the above-mentioned settings, not only can micro-nano ozone water be introduced into the cleaning pool nozzle inlet 25 to clean the wafer 33, but also the heating water in the heating pool 4 can be introduced to rinse the wafer 33, or the ozone gas of the ozone generator 3 can be introduced to dry the wafer 33.

[0041] In a preferred embodiment, the filter 8 is provided 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, the filtered water outlet 35 is connected to the circulating water inlet 36 of the heating tank 4, and the circulating water discharged from the filter 8 enters the heating tank 4. Sewage enters the filter 8 through the sewage inlet 31 of the filter 8, is filtered through the filter membrane, and the filtered circulating water is discharged from the filtered water outlet 35 and enters the heating tank 4 through the circulating water inlet 36 of the heating tank 4. The drain outlet 34 is connected to the sewage tank or directly discharged, and the sewage filtered by the filter 8 flows out from the drain outlet 34.

[0042] 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, 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.

[0043] More preferably, if 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, and the water source solenoid valve 15 and the oxygen source solenoid valve 16 through the IO port.

[0044] 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 heater 13 in the heating pool 4 to operate so that the temperature of the micro-nano ozone water reaching the cleaning pool 7 is maintained between 35 and 38°C; the PLC controller 9 is connected to a heating pool liquid level sensor 14, a water source solenoid valve 15, and a 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.

[0045] More preferably, if 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 through the 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 to adjust the working 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 to control the working parameters of the heater 13.

[0046] The multi-angle micro-nano bubble cleaning system for wafers according to the embodiment of the present invention provides a preferred cleaning process as follows: 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, and then introduced into the micro-nano bubble generator 6. At the same time, heating water at 35-38° C. in the heating pool 4 is introduced into the micro-nano bubble generator 6. The ozone gas and the heating water are mixed in a gas-liquid ratio of 1:15-1:12 to generate micro-nano ozone water. 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; 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 at the same time, let the removed stains settle at the bottom of the cleaning tank 7 and then drain to the filter 8; Then, the heated water in the heating pool 4 is injected into the cleaning pool 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; Then, the cleaning nozzle 28 cyclically swings and sprays the ozone gas in the ozone generator 3 into the cleaning tank, which further removes the residual organic matter on the surface and dries the wafer 33. At this point, the cleaned wafer is taken out to complete a working cycle.

[0047] It will be easily understood by those skilled in the art that the above description is only 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 protection scope of the present invention.

Claims

1. A multi-angle micro-nano bubble cleaning system for wafers, characterized in that: It includes ozone generator, heating tank, micro-nano bubble generator, cleaning tank, 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 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; the cleaning station is used to place wafers, and the cleaning nozzles are located below the wafers at the cleaning station; the lower end of each cleaning nozzle is hinged to an auxiliary mounting structure above the bottom of the cleaning pool through a pin shaft; 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 also includes a cleaning pool nozzle inlet, and the cleaning pool nozzle inlet is connected to each cleaning nozzle; 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.

3. The multi-angle micro-nano bubble cleaning system for wafers according to claim 1, characterized in that: The cleaning pool also includes a quick water injection port, which is connected to the outlet of the micro-nano bubble generator; and / or, 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 comprises 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 at 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 inner side 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 grooves 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 the 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 two long rods are respectively rotated by cooperating with the keyways through cylindrical rollers arranged on the sides, and the two ends of the two long rods are respectively connected by bolts to clamp 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 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 an external water source through a water source solenoid valve, and the heating water outlet is connected to a micro-nano bubble generator through a circulating pump.

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, wherein the oxygen inlet is connected to an oxygen source through an oxygen source solenoid valve, and the ozone outlet is connected to a 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 a 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 tank, the filtered water outlet is connected to the inlet of the heating tank, and the drain outlet is connected to the sewage tank or directly discharged.

10. A micro-nano bubble cleaning method for wafers, implemented by 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 generate ozone gas with a concentration of 150-200ppm, which is then introduced into the micro-nano bubble generator; at the same time, the heating water at 35-38℃ in the heating pool is introduced into the micro-nano bubble generator, and the ozone gas and the heating water are mixed in a gas-liquid ratio of 1:15-1:12 to generate 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 circulate and oscillate the micro-nano ozone water 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 from top to bottom for 10-12 minutes, and then drain the waste water to the filter; The cleaning nozzle sprays ozone gas into the cleaning tank in a cyclic swing to remove residual organic matter on the surface and dry the wafer, completing the wafer cleaning.

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