Wafer cleaning tank

Abstract

The utility model provides a wafer cleaning tank, which relates to the technical field of wafer cleaning and comprises a plurality of liquid inlet pipelines arranged at a tank opening of the wafer cleaning tank, and each liquid inlet pipeline is connected with a liquid storage tank; and the splash-proof ring is arranged in the wafer cleaning tank and floats along with liquid in the wafer cleaning tank, and a wafer taking opening is formed in the splash-proof ring. The system has the beneficial effects that the use of complex equipment such as a plurality of metering tanks, metering pumps and flowmeters is avoided, and the system configuration is obviously simplified, so that the overall equipment cost is reduced, the hardware requirement is reduced, and the installation, maintenance and operation costs are also reduced. Due to the design of the splash-proof ring, the splash-proof ring can float along with liquid in the cleaning tank to automatically adapt to different liquid levels, and the splashing phenomenon caused by too high flow speed or impact when liquid medicine is injected can be effectively prevented. The design directly solves the problems of inaccurate liquid preparation proportion and environmental pollution caused by liquid splashing in the prior art, and ensures the cleanliness of the cleaning environment and the accuracy of the liquid mixing proportion.

Description

TECHNICAL FIELD

[0001] The utility model relates to wafer cleaning technical field especially relates to a wafer cleaning tank. BACKGROUND

[0002] In the precision process of semiconductor wet cleaning, multiple chemicals are often mixed into the process tank in precise proportion, aiming at efficiently removing impurity particles on the wafer surface. Traditionally, this mixing process relies on a complex configuration system, including multiple carefully designed measuring tanks equipped with precise capacitive sensors to accurately control the volume of chemicals entering the process tank, ensuring that the strict requirements of the process on the mixing ratio are met. The liquid supplementing operation adopts a fixed supplement strategy, that is, the required volume of solution is accurately extracted from the measuring tank by a measuring pump or a high-precision flow meter, and smoothly injected into the process tank to maintain the constancy of the mixing ratio.

[0003] However, this system not only involves a large number of hardware devices such as measuring tanks, measuring pumps and flow meters, resulting in high cost, but also occupies a large amount of valuable production space due to its complex configuration and operation process, which poses a challenge to the optimal layout of the semiconductor manufacturing environment.

[0004] On the other hand, although there have been attempts to simplify the injection of chemicals by directly connecting pipes, aiming to reduce device occupation, in actual operation, due to improper flow rate control, pipe design defects and other factors, the problem of chemical splashing is often caused. This not only directly affects the accuracy of the mixing ratio, but also may cause pollution to the processing environment with extremely high cleanliness requirements, thereby affecting product quality and production efficiency.

[0005] In summary, although the existing semiconductor wet cleaning mixing technology has its own advantages, there is still room for improvement, especially in terms of reducing cost, simplifying process, reducing space occupation and avoiding environmental pollution, and innovative solutions are urgently needed. SUMMARY

[0006] In view of the problems existing in the prior art, the utility model provides a wafer cleaning tank, comprising:

[0007] A plurality of liquid inlet pipes are arranged at the slot of the wafer cleaning tank, and each liquid inlet pipe is connected to a liquid storage tank.

[0008] A splash-proof ring is arranged inside the wafer cleaning tank and floats with the liquid inside the wafer cleaning tank, and a wafer taking opening is formed in the splash-proof ring.

[0009] Preferably, the splash-proof ring comprises:

[0010] A plurality of floating balls are arranged in the splash-proof ring, and each floating ball is hollow.

[0011] The installation ring is provided with a plurality of supporting rods at the bottom, and each of the supporting rods is provided with a floating ball at the end.

[0012] Preferably, the installation ring is provided with a detachable flexible net.

[0013] Preferably, the installation ring is further provided with a filter screen under the flexible net.

[0014] Preferably, the mesh number of the filter screen is greater than that of the flexible net.

[0015] Preferably, the installation ring is provided with a flip-open access cover plate covering the wafer access port.

[0016] Preferably, the liquid inlet pipe is provided with an electromagnetic valve and a flow meter.

[0017] Preferably, the liquid inlet pipe is further provided with a switch electrically connected with the electromagnetic valve, and the switch corresponds to the edge position of the splash-proof ring.

[0018] Preferably, the switch is a press switch or an inductive switch.

[0019] Preferably, the wafer cleaning tank comprises an inner tank and an outer tank, the liquid outlet of the liquid inlet pipe corresponds to the inner tank, and each of the liquid inlet pipes is further provided with a branch pipe, and the pipe opening of the branch pipe corresponds to the outer tank.

[0020] The above technical solution has the following advantages or beneficial effects:

[0021] 1. The plurality of liquid inlet pipes are directly connected with the liquid storage tank and the cleaning tank, avoiding the use of complex devices such as multiple measuring tanks, measuring pumps and flow meters, significantly simplifying the system configuration, thereby reducing the overall equipment cost. This direct connection method not only reduces the hardware requirement, but also reduces the installation, maintenance and operation cost.

[0022] 2. The nitrogen micro-pressure differential liquid level meter is further provided in the cleaning tank, and the flow meter is further provided on the liquid inlet pipe. Through the cooperation of the nitrogen micro-pressure differential liquid level meter and the flow meter, the amount of various types of liquid added in the cleaning tank can be accurately controlled, and the precise proportioning of the cleaning liquid can be realized.

[0023] 3. The splash-proof ring can not only float with the liquid in the cleaning tank and automatically adapt to different liquid levels, but also effectively prevent the splashing phenomenon caused by too fast flow rate or impact when the liquid is injected. This design directly solves the problems of inaccurate liquid proportioning and environmental pollution caused by liquid splashing in the prior art, ensuring the cleanliness of the cleaning environment and the accuracy of the mixed liquid proportion. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1As a preferred embodiment of the utility model, a top view of a wafer cleaning tank is provided.

[0025] Figure 2 As a preferred embodiment of the utility model, a side sectional view of a wafer cleaning tank is provided.

[0026] Figure 3 As a preferred embodiment of the utility model, a structure diagram of a splash-proof ring is provided.

[0027] Figure 4 As a preferred embodiment of the utility model, a structure diagram of a wafer cleaning tank is provided.

[0028] Reference signs:

[0029] 1, liquid inlet pipeline; 11, electromagnetic valve; 12, flow meter; 13, switch; 14, branch pipeline; 2, wafer cleaning tank; 21, inner tank; 22, outer tank; 3, liquid storage tank; 4, splash-proof ring; 41, wafer taking opening; 42, floating ball; 43, mounting ring; 44, supporting rod; 45, flexible net; 46, filter screen; 47, taking opening cover plate; 5, nitrogen micro-pressure differential liquid level meter; 51, pressure regulating valve; 52, speed regulating valve; 53, gas filter; 54, nitrogen liquid level meter body. DETAILED DESCRIPTION

[0030] The utility model will be explained in detail below in combination with the drawings and specific embodiments. The utility model is not limited to the embodiment, and other embodiments can also belong to the scope of the utility model as long as they meet the main idea of the utility model.

[0031] As a preferred embodiment of the utility model, based on the above-mentioned problems existing in the prior art, a wafer cleaning tank is provided, as shown in the figure, which comprises: Figures 1-3

[0032] A plurality of liquid inlet pipelines 1 are arranged at the tank opening of the wafer cleaning tank 2, and each liquid inlet pipeline 1 is connected with a liquid storage tank 3.

[0033] A splash-proof ring 4 is arranged in the interior of the wafer cleaning tank 2 and floats with the liquid in the interior of the wafer cleaning tank 2, and the wafer taking opening 41 is arranged on the splash-proof ring 4.

[0034] Specifically, in the embodiment, the wafer cleaning tank provided by the technical solution shows significant advantages in view of the shortcomings existing in the prior art semiconductor wet cleaning technology, and the specific advantages are as follows:

[0035] ​The present solution directly connects the liquid storage tank and the cleaning tank through multiple liquid inlet pipes, avoiding the use of multiple metering tanks, metering pumps, flow meters and other complex equipment, significantly simplifying the system configuration and thus reducing the overall equipment cost. This direct connection not only reduces hardware requirements but also lowers installation, maintenance and operation costs.

[0036] Due to the reduction of a large number of auxiliary equipment, the present solution is more efficient in space utilization. The multiple liquid inlet pipes are compactly arranged at the cleaning tank opening, without occupying additional space, while the splash-proof ring as an internal component does not increase the external space requirement, making the entire cleaning system more compact and adapting to the high requirements for space utilization in the semiconductor manufacturing environment.

[0037] The design of the splash-proof ring not only can float with the liquid in the cleaning tank and automatically adapt to different liquid levels, but also can effectively prevent the splashing phenomenon caused by too fast flow rate or impact when the liquid is injected. This design directly solves the problems of inaccurate liquid proportioning and environmental pollution caused by liquid splashing in the prior art, ensuring the cleanliness of the cleaning environment and the accuracy of the mixed liquid proportion.

[0038] Each liquid inlet pipe is directly connected to one liquid storage tank, meaning that the injection of different chemicals can be independently controlled, increasing the flexibility and accuracy of operation. This design facilitates the adjustment of chemical proportioning according to specific cleaning needs, improving cleaning efficiency and effectiveness. At the same time, the design of the wafer pickup opening facilitates the safe and convenient removal or insertion of wafers without disturbing the cleaning process, improving the overall operation flow and efficiency.

[0039] In summary, the present solution solves the key problems in the existing semiconductor wet cleaning technology by simplifying equipment configuration, optimizing space utilization, effectively preventing liquid splashing and improving operation convenience and flexibility, providing a more efficient, economical and environmentally friendly wafer cleaning solution for the semiconductor manufacturing industry.

[0040] In a preferred embodiment of the present utility model, as shown in Figure 2 , Figure 3 The splash-proof ring 4 includes:

[0041] A plurality of hollow floating balls 42;

[0042] A mounting ring 43, the bottom of which is provided with a plurality of support rods 44, and each support rod 44 is provided with a floating ball 42 at the end.

[0043] Specifically, the present embodiment further refines the design of the splash-proof ring 4 in the foregoing embodiment, i.e., adopts a combination structure of multiple hollow floating balls 42, a mounting ring 43 and support rods 44, which brings the following significant advantages:

[0044] Each hollow floating ball 42 can provide better buoyancy support when floating on the liquid in the cleaning tank, allowing the entire splash guard 4 to float up and down more stably with the liquid level changes. This design not only ensures that the splash guard maintains an effective splash barrier at different liquid levels, but also improves its stability in dynamic environments, effectively preventing splash failure due to shaking or misalignment.

[0045] The floating balls 42 are connected to the mounting ring 43 by support rods 44, which allows the splash guard to adapt to different sizes of wafer cleaning tanks. The mounting ring 43 serves as the overall framework, ensuring the structural integrity and stability of the splash guard, while the number and position of the floating balls 42 can be adjusted according to the actual size of the cleaning tank, providing higher flexibility and adaptability.

[0046] The hollow floating balls 42 also take into account the principles of fluid dynamics. When the liquid is injected, the floating balls can effectively disperse the water flow impact force, reducing direct water flow impact and splashing. At the same time, the floating characteristics of the floating balls can also buffer and absorb the kinetic energy of the water flow to a certain extent, further reducing the risk of liquid splashing.

[0047] In summary, the splash guard design using multiple hollow floating balls 42 combined with the mounting ring 43 and support rods 44 not only enhances the splash effect and stability, improves adaptability and fluid dynamics performance, but also simplifies the installation and maintenance process, and exhibits good cost-effectiveness, providing an efficient and practical solution for the splash guard design of wafer cleaning tanks.

[0048] In the preferred embodiment of the present utility model, as shown in the mounting ring 43 is provided with detachable flexible net 45. Figure 1

[0049] Specifically, in this embodiment, the splash effect of the splash guard 4 is mainly realized by the flexible net 45. When the liquid is injected into the cleaning tank at a certain speed, it will generate a certain impact force. The flexibility and elasticity of the flexible net 45 can absorb and disperse this impact force, reducing the splashing phenomenon of the liquid due to impact.

[0050] Further, the length of the support rod 44 also ensures that there is always a distance from the flexible net 45 to the liquid level surface. Even if the liquid entering the wafer cleaning tank 2 through the flexible net 45 splashes on the liquid level surface, the splashed liquid can be blocked by the reverse side of the flexible net 45, preventing it from splashing outside the wafer cleaning tank 2.

[0051] In the preferred embodiment of the present utility model, as shown in the mounting ring 43 is provided with detachable flexible net 45. Figures 1-3

[0052] In the preferred embodiment of the present utility model, the mesh number of the filter screen 46 is greater than that of the flexible net 45.​​

[0053] Specifically, in the anti-splashing ring design of the wafer cleaning tank in this embodiment, a filter screen 46 is added under the flexible screen 45, and the mesh number of the filter screen 46 is larger, meaning that the mesh holes are finer. Different chemicals may contain different sizes and types of impurities. By setting flexible screens 45 and filter screens 46 with different mesh numbers, the appropriate filtration level can be selected according to the characteristics of the chemical solution, thereby ensuring the best filtration effect.

[0054] The finer filter screen 46 can capture more tiny impurities, thereby improving the cleanliness and consistency of the cleaning process. This multi-layer filtration mechanism ensures the purity of the cleaning liquid, reducing the risk of contamination on the wafer surface. This is crucial for the semiconductor manufacturing industry, as any tiny contamination can lead to reduced product performance or yield.

[0055] The detachable design of the flexible screen 45 and the filter screen 46 makes maintenance and replacement easy. When the filter screen is clogged or damaged due to long-term use, the filter screen can be removed and cleaned or replaced individually without disassembling the entire anti-splashing ring.

[0056] By setting a multi-layer filtration mechanism, the service life of the lower filter screen 46 can be extended. Because larger impurities are first intercepted by the flexible screen 45, the risk of clogging the filter screen 46 is reduced, thereby extending its service life.

[0057] In summary, by setting a filter screen 46 with a larger mesh number than the flexible screen 45 in the mounting ring 43, this innovative design not only enhances the filtration effect and improves the cleaning quality, but also exhibits good flexibility and adaptability, cost-effectiveness and sustainability. This design undoubtedly brings new breakthroughs and developments to the anti-splashing and filtration mechanism of the wafer cleaning tank.

[0058] In the preferred embodiment of the utility model, the mounting ring 43 is provided with a flip-open access cover 47, which covers the wafer access port 41.

[0059] In the preferred embodiment of the utility model, the inlet pipeline 1 is provided with a solenoid valve 11 and a flow meter 12.

[0060] Specifically, in this embodiment, a liquid level meter is also provided in the wafer cleaning tank 2, and the inlet pipeline 1 includes a pure water inlet pipeline and a chemical solution inlet pipeline. The required water and chemical solution ratio is calculated in advance to determine the volume of the added liquid through the solenoid valve and the flow meter. The use process is as follows:

[0061] 1. Preparation stage:

[0062] Before starting the cleaning, first ensure that all equipment such as the wafer cleaning tank, the inlet pipeline, the solenoid valve, the flow meter, and the liquid level meter are in normal working condition.

[0063] According to the cleaning process requirements, the required pure water and chemical liquid ratio is calculated in advance. This ratio is usually determined based on the type of wafer, the degree of pollution and the cleaning target.

[0064] 2. Set parameters:

[0065] The calculated pure water and chemical liquid ratio is input into the control system. The control system will control the addition of the two liquids through solenoid valves and flow meters according to this ratio.

[0066] At the same time, check if the liquid level meter is in normal working condition and ensure that it can accurately reflect the change of liquid level in the cleaning tank.

[0067] 3. Start liquid addition:

[0068] Start the cleaning program, the control system will first open the solenoid valve of the pure water inlet pipe, allowing pure water to enter the cleaning tank according to the preset flow rate.

[0069] At the same time, the flow meter will monitor the actual flow rate of pure water and compare it with the preset value to ensure the accuracy of the flow rate.

[0070] When the pure water reaches the preset addition amount, the control system will automatically close the solenoid valve of the pure water inlet pipe.

[0071] 4. Add chemical liquid:

[0072] Then, the control system will open the solenoid valve of the chemical liquid inlet pipe, allowing the chemical liquid to enter the cleaning tank according to the preset flow rate.

[0073] Similarly, the flow meter will monitor the actual flow rate of the chemical liquid and compare it with the preset value to ensure the accuracy of the flow rate.

[0074] When the chemical liquid reaches the preset addition amount, the control system will automatically close the solenoid valve of the chemical liquid inlet pipe.

[0075] 5. Liquid level monitoring:

[0076] During the entire liquid addition process, the liquid level meter will continuously monitor the change of liquid level in the cleaning tank.

[0077] If the liquid level reaches the preset maximum value and there is still liquid being injected at this time (although the solenoid valve should have been closed in theory, but to be safe), the switch located on the inlet pipe (such as the switch corresponding to the edge of the splash-proof ring mentioned earlier) will be triggered, further ensuring that the solenoid valve is closed to prevent liquid overflow.

[0078] 6. Cleaning phase:

[0079] When the pure water and chemical liquid are added according to the preset ratio and volume, the liquid in the cleaning tank will start to contact and react with the wafer for cleaning.

[0080] According to the requirements of the cleaning process, it is possible to control the cleaning time, temperature, stirring speed and other parameters to ensure the cleaning effect.

[0081] 7. Discharge and cleaning aftertreatment:

[0082] After the cleaning is completed, the liquid in the cleaning tank is discharged.

[0083] The cleaning tank is cleaned and disinfected as necessary to ensure cleanliness and safety for the next use.

[0084] As shown in FIG. Figure 4 The liquid level meter in the wafer cleaning tank 2 uses a nitrogen micro-pressure differential liquid level meter 5, which includes a pressure regulating valve 51, a speed regulating valve 52, a gas filter 53, and a nitrogen liquid level meter body 54. Figure 4 From A, high-purity nitrogen gas is input, from B, pure water is input, and from C, D, and E, chemical liquid is input.

[0085] By using the nitrogen micro-pressure differential liquid level meter 5 and other flow meters 12 together, not only can the equipment be simplified, but also the amount of various types of liquid added to the wafer cleaning tank can be accurately controlled, and the precise proportioning of the cleaning liquid can be achieved. The specific steps are as follows:

[0086] S1. Calculate the volume of the wafer cleaning tank 2 and then calculate the required volume of the corresponding liquid by proportioning;

[0087] S2. Perform water replenishment in the inner tank 21 of the wafer cleaning tank 2, and determine the required liquid level of the pure water in the wafer cleaning tank 2 through the nitrogen micro-pressure differential liquid level meter 5;

[0088] S3. Open the electromagnetic valve 11 on the liquid inlet pipeline 1 to supplement the chemical liquid to the inner tank 21 of the wafer cleaning tank 2, determine the addition amount of the chemical liquid through the flow meter 12, and finally achieve the required chemical liquid proportioning, and close the electromagnetic valve 11 on the liquid inlet pipeline 1.

[0089] According to the process requirements, the outer tank 22 of the wafer cleaning tank 2 can also be supplemented with chemical liquid in a timed or quantitative manner through the flow meter 12.

[0090] In a preferred embodiment of the present application, the liquid inlet pipeline 1 is also provided with a switch 13 electrically connected to the electromagnetic valve 11, and the switch 13 corresponds to the edge position of the splash-proof ring 4.

[0091] Specifically, by setting the switch 13 corresponding to the edge position of the splash-proof ring 4, the automatic control of the liquid level is realized. When the liquid level rises to a certain extent (the liquid level reaches the maximum value of the wafer cleaning tank), the splash-proof ring 4 will touch the switch 13, thereby triggering the electromagnetic valve 11 to close, preventing the liquid from continuing to be injected, and avoiding the overflow or safety hazards caused by the high liquid level.

[0092] The automatic liquid level control mechanism reduces the need for human intervention and reduces the safety risks caused by improper or negligent operation. Even if the operator fails to notice the change in the liquid level in time, the system can automatically stop the liquid from being injected, ensuring the safety of the equipment and personnel.

[0093] In the preferred embodiment of the utility model, the switch 13 is a push switch or an inductive switch.

[0094] In the preferred embodiment of the utility model, as shown in the figure, Figures 1-3 The wafer cleaning tank 2 includes an inner tank 21 and an outer tank 22, and the liquid outlet of the liquid inlet pipeline 1 corresponds to the inner tank 21. Each liquid inlet pipeline 1 is also provided with a branch pipeline 14, and the pipe opening of the branch pipeline 14 corresponds to the outer tank 22.

[0095] The above is only the preferred embodiment of the utility model, and does not limit the implementation and protection scope of the utility model. For those skilled in the art, it should be realized that any equivalent replacement and obvious change made by applying the contents of the specification and drawings should be included in the protection scope of the utility model.

Claims

1. A wafer cleaning tank, characterized by, The application relates to a wafer cleaning tank, which comprises the following parts: a plurality of liquid inlet pipes arranged in the tank opening of the wafer cleaning tank, each of the liquid inlet pipes being connected with a liquid storage tank; a splash-proof ring arranged in the interior of the wafer cleaning tank and floating with the liquid in the interior of the wafer cleaning tank, the splash-proof ring being provided with a wafer taking opening.

2. The wafer cleaning tank of claim 1, wherein The splash-proof ring comprises: a plurality of hollow floating balls; a mounting ring, the bottom of the mounting ring being provided with a plurality of supporting rods, and the end of each of the supporting rods being provided with a floating ball.

3. The wafer cleaning tank of claim 2, wherein, A detachable flexible net is arranged in the mounting ring.

4. The wafer cleaning tank of claim 3, wherein A filter screen is further arranged in the mounting ring under the flexible net.

5. The wafer cleaning tank of claim 4, wherein, The mesh number of the filter screen is greater than that of the flexible net.

6. The wafer cleaning tank of claim 2, wherein An openable and reversible taking opening cover plate is arranged in the mounting ring and covers the wafer taking opening.

7. The wafer cleaning tank of claim 1, wherein An electromagnetic valve and a flow meter are arranged on the liquid inlet pipe.

8. The wafer cleaning tank of claim 7, wherein, A switch electrically connected with the electromagnetic valve is further arranged on the liquid inlet pipe, and the switch corresponds to the edge position of the splash-proof ring.

9. The wafer cleaning tank of claim 8, wherein, The switch is a press switch or an inductive switch.

10. The wafer cleaning tank of claim 1, wherein, The wafer cleaning tank comprises an inner tank and an outer tank, the liquid outlet of the liquid inlet pipe corresponds to the inner tank, and a branch pipe is further arranged on each of the liquid inlet pipes, and the pipe opening of the branch pipe corresponds to the outer tank.

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