Degumming liquid recovery system

Abstract

The utility model provides a degumming liquid recovery system, which relates to the technical field of silicon wafer degumming, and comprises a first circulation loop, the first circulation loop comprises a degumming tank, a collecting device, a purifying assembly and a blending assembly which are connected in sequence; the purification assembly comprises a first purification assembly and a second purification assembly, and the first purification assembly and the collection device form a second circulation loop. The device has the beneficial effects that the degumming liquid can be filtered and recovered, and in the process of filtering and recovering the degumming liquid, substances such as metal ions and lactic acid are filtered, so that the problem of smudginess caused by enrichment of silicon powder and metal ions in the degumming tank is solved, the risk of smudginess of silicon wafers is reduced, the pressure of a cleaning process is relieved, and the working efficiency is improved. And the regeneration liquid can have a longer service life.

Description

Technical Field

[0001] This utility model relates to the field of silicon wafer debonding technology, and in particular to a debonding liquid recovery system. Background Technology

[0002] Silicon wafer debonding is the process of separating silicon wafers from the wafer holder, which is crucial for improving wafer quality and subsequent processing. The debonding process includes physical and chemical methods. Physical methods include spray cleaning, ultrasonic cleaning, and overflow cleaning, while chemical methods use specific chemical reagents, namely debonding solutions, to soften the adhesive, allowing the silicon wafer to detach from the wafer holder.

[0003] Current degumming processes typically involve adding degumming solution per pass, discharging the degumming solution to a wastewater treatment plant every 30 days, and then replacing the degumming solution. The applicant has identified at least the following technical problems with this existing technology:

[0004] To save costs, the liquid replacement cycle is generally long. During the debonding process, a large amount of silicon powder is introduced into the debonding tank. As time goes on, the concentration of silicon powder increases. On the one hand, the silicon powder is carried into the cleaning process after debonding, which causes high pressure in the cleaning process and makes it difficult to clean the silicon wafers. On the other hand, the waste liquid containing high concentration of silicon powder is directly discharged, resulting in the waste of effective components. Utility Model Content

[0005] The purpose of this invention is to provide a degumming liquid recovery system to solve the problems existing in the prior art. To save costs, the liquid replacement cycle is generally long, resulting in a large amount of silicon powder being introduced into the degumming tank during the silicon wafer degumming process. As time goes on, the silicon powder concentration increases. On the one hand, this leads to high pressure and difficulty in cleaning the silicon wafers after degumming; on the other hand, the direct discharge of waste liquid containing high concentrations of silicon powder results in the waste of effective components. The various technical effects of the preferred technical solutions provided by this invention are detailed below.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The present invention provides a degumming liquid recovery system, comprising a first circulation loop, wherein the first circulation loop includes a degumming tank, a collection device, a purification component and a mixing component connected in sequence; the purification component includes a first purification component and a second purification component, and the first purification component and the collection device constitute a second circulation loop.

[0008] Preferably, the first purification component includes a first filter device and a filter press device connected in series, and the second circulation loop includes the collection device, the first filter device and the filter press device connected in series.

[0009] Preferably, the filter diameter of the first filtration device is 1nm-5nm, used to separate the filtrate into a first clear liquid and a first dirty liquid.

[0010] Preferably, the first filtration device includes a first outlet and a second outlet;

[0011] The first outlet of the first filter device is connected to the second purification component, and is used to deliver the first clear liquid to the second purification component;

[0012] The second outlet is connected to the filter press and is used to transport the first dirty liquid to the filter press.

[0013] Preferably, the filter press includes a third outlet and a fourth outlet;

[0014] The third outlet of the filter press is connected to the collection device, and is used to transport the filtrate after filter pressing to the collection device;

[0015] The fourth outlet is used to discharge the solids formed after pressure filtration.

[0016] Preferably, the second purification component includes a second filtration device with a filter diameter of 0.8 nm to 2 nm, used to separate the filtrate into a second clear liquid and a second dirty liquid.

[0017] Preferably, the second filter device includes a fifth outlet and a sixth outlet;

[0018] The fifth outlet of the second filtration device is connected to the mixing assembly and is used to deliver the second clear liquid to the mixing assembly;

[0019] The sixth outlet is used to discharge the second dirty fluid.

[0020] Preferably, the first filtration device comprises a PEK tubular membrane;

[0021] And / or, the second filtration device includes a nanofiltration membrane.

[0022] Preferably, the degumming tank, the collecting device, the purification component, and the mixing component are connected by pipes, and fluid transfer is carried out under the action of overflow or pump.

[0023] Preferably, the pipeline is equipped with at least one solenoid valve for controlling fluid transmission.

[0024] The degumming liquid recovery system provided by this utility model, by setting up a first circulation loop including a degumming tank, a collection device, a purification component, and a mixing component, can filter and recover degumming liquid. The mixing component automatically adds new effective components to the purified recovery liquid according to the composition of the degumming liquid, meeting the usage requirements of the degumming liquid. The purification component includes a first purification component and a second purification component. The first purification component and the collection device form a second circulation loop. During the filtration and recovery process of the degumming liquid, the cooperation of the first and second purification components filters out silicon powder concentrate, metal ions, lactic acid, and other substances, changing the problem of silicon powder and metal ion accumulation and contamination in the degumming tank, reducing the risk of silicon wafer contamination, alleviating the pressure of the cleaning process, and enabling the regenerated liquid to have a longer service life. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of an embodiment of the degumming liquid recovery system of this utility model;

[0027] Figure 2 This is a schematic diagram of the purification component in the degumming liquid recovery system of this utility model;

[0028] Figure 3 This is a schematic diagram of the second circulation loop in the degumming liquid recovery system of this utility model.

[0029] In the diagram: 1. Degumming tank; 2. Collection device; 3. Purification component; 31. First filter device; 32. Second filter device; 33. Filter press device; 4. Mixing component; 10. First pipeline; 100. First outlet; 200. Second outlet; 300. Third outlet; 400. Fourth outlet; 500. Fifth outlet; 600. Sixth outlet. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be described in detail below. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0031] Figure 1This is a structural schematic diagram of this embodiment, as shown below. Figure 1 As shown, this utility model provides a degumming liquid recovery system. The system includes a first circulation loop, which comprises a degumming tank 1, a collection device 2, a purification component 3, and a mixing component 4. The collection device 2 collects the degumming liquid discharged from the degumming tank 1; the purification component 3 purifies the degumming liquid circulating from the collection device 2 to the purification component 3; the mixing component 4, on the one hand, can receive the degumming liquid purified by the purification component for reuse; on the other hand, the mixing component 4 includes an automatic liquid dispensing system, capable of preparing a degumming liquid of a predetermined concentration and supplying it to the degumming tank 1.

[0032] Specifically, Figure 1 and Figure 2 As shown, the purification component 3 in this embodiment includes a first purification component and a second purification component. The first purification component and the collection device 2 constitute a second circulation loop. The first purification component is used to initially purify the degumming liquid and discharge the concentrated silicon powder solution. The second purification component is used to further filter and purify the degumming liquid purified by the first purification component, mainly filtering out metal ions.

[0033] This degumming liquid recovery system, through the setting of a first circulation loop including a degumming tank 1, a collection device 2, a purification component 3, and a mixing component 4, can filter and recover the degumming liquid. The mixing component automatically adds new effective components to the purified recovery liquid according to the composition of the degumming liquid, meeting the usage requirements of the degumming liquid. The purification component includes a first purification component and a second purification component. The first purification component and the collection device 2 form a second circulation loop. During the filtration and recovery process of the degumming liquid, the cooperation of the first and second purification components filters out substances such as silicon powder concentrate, metal ions, and lactic acid, changing the problem of silicon powder and metal ion accumulation and contamination in the degumming tank, reducing the risk of silicon wafer contamination, alleviating the pressure of the cleaning process, and extending the service life of the regenerated liquid.

[0034] As an optional implementation method, such as Figures 1-3 As shown, the first purification component includes a first filter device 31 and a filter press device 33 connected in series, and the second circulation loop includes a collection device 2, a first filter device 31 and a filter press device 33 connected in series.

[0035] In this embodiment, the first filtration device 31 has a filtration diameter of 1nm-5nm and is used to separate the filtrate into a first clear liquid and a first dirty liquid.

[0036] The first filtration device 31 includes a first outlet 100 and a second outlet 200; the first outlet 100 of the first filtration device 31 is connected to the second purification component and is used to transport the first clean liquid to the second purification component; the second outlet 200 is connected to the filter press 33 and is used to transport the first dirty liquid to the filter press 33.

[0037] Specifically, the first filtration device 31 in this embodiment includes a filter membrane. Optionally, the filter membrane includes a PEK tubular membrane, which is used to transport the filtered silicon powder concentrate to the pressure filter device 33 and to transport water, small silicon powder particles, metal ions, lactic acid and other substances with small molecular weights to the second purification component.

[0038] As an optional implementation, the filter press 33 includes a third outlet 300 and a fourth outlet 400; the third outlet 300 of the filter press 33 is connected to the collection device 2 and is used to transport the filtrate after filtration to the collection device; the fourth outlet 400 is used to discharge the solids formed after filtration.

[0039] In this embodiment, the filter press device 33 is a filter press. By setting up a filter press, the problem of direct discharge of high concentration of silicon powder with waste liquid is solved, avoiding the waste of effective components. The solid silicon mud after being filtered by the filter press can be recycled with a high recovery rate.

[0040] As an optional implementation, the second purification component includes a second filtration device with a filter diameter of 0.8 nm to 2 nm, used to separate the filtrate into a second clear liquid and a second dirty liquid.

[0041] The second filtration device includes a fifth outlet 500 and a sixth outlet 600. The fifth outlet 500 is connected to the mixing assembly 4 and is used to transport the second clear liquid to the mixing assembly. The sixth outlet 600 is used to discharge the second dirty liquid. Optionally, solenoid valves are provided at the fifth outlet 500 and the sixth outlet 600 to effectively control the discharge of the filtrate.

[0042] The second filtration device in this embodiment includes a nanofiltration membrane. In use, the second filtration device can trap metal ions, circulating moisture and effective substances to the blending component 4. Impurities containing metal ions are filtered out and discharged as waste liquid. By employing a metal ion membrane filtration method, only periodic membrane replacement is required, which, compared to ion exchange resins requiring periodic regeneration with strong acid, offers better safety and environmental friendliness.

[0043] As an optional implementation, the degumming tank 1, the collecting device 2, the purification component 3, and the mixing component 4 are connected by pipes, and fluid is transferred under the action of overflow or pump. At least one solenoid valve is installed on the pipes to control the fluid transfer.

[0044] Specifically, in this embodiment, the mixing component 4 includes a mixing tank, and the mixing component 4 is connected to the degumming tank 1 through a first pipeline 10, on which a solenoid valve is provided.

[0045] By setting up the mixing component 4, a desizing solution of a predetermined concentration can be prepared according to usage needs. For example, new active ingredients can be added back to the desizing solution according to its composition, and then circulated into the desizing tank 1 through the first pipeline 10 for use, continuously replenishing the desizing tank 1 with new solution. Through continuous replenishment of new solution and overflow, the desizing solution is effectively purified, reducing the concentration of silicon powder and metal ions, reducing the risk of silicon wafer contamination, and at the same time, alleviating the pressure on the cleaning process.

[0046] In this embodiment, the degumming tank 1 includes an overflow port, which allows the degumming liquid to overflow into the collection device 2. In this embodiment, by providing an overflow port in the degumming tank 1, the degumming liquid in the degumming tank 1 is discharged through the overflow port, and new liquid is continuously added by the mixing component 4 to form a cycle.

[0047] By adopting this degumming liquid recovery system, the degumming liquid recovery rate reaches over 95%. During the entire purification process, except for a small amount of concentrated metal ions that need to be discharged, there is basically no loss. At the same time, the purification process allows the degumming liquid to have a longer service life.

[0048] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the protection scope of the claims.

Claims

1. A degumming liquid recovery system, characterized in that, It includes a first circulation loop, which includes a degumming tank, a collection device, a purification component, and a mixing component connected in sequence; the purification component includes a first purification component and a second purification component connected in sequence, and the first purification component and the collection device constitute a second circulation loop.

2. The degumming liquid recovery system according to claim 1, characterized in that: The first purification component includes a first filter device and a filter press device connected in series; the second circulation loop includes a collection device, a first filter device, and a filter press device connected in series.

3. The degumming liquid recovery system according to claim 2, characterized in that: The first filtration device includes a PEK tubular membrane for separating the filtrate into a first clear liquid and a first dirty liquid.

4. The degumming liquid recovery system according to claim 3, characterized in that: The first filtration device includes a first outlet and a second outlet; The first outlet of the first filter device is connected to the second purification component, and is used to deliver the first clear liquid to the second purification component; The second outlet is connected to the filter press and is used to transport the first dirty liquid to the filter press.

5. The degumming liquid recovery system according to any one of claims 2-4, characterized in that: The filter press includes a third outlet and a fourth outlet; The third outlet of the filter press is connected to the collection device, and is used to transport the filtrate after filter pressing to the collection device; The fourth outlet is used to discharge the solids formed after pressure filtration.

6. The degumming liquid recovery system according to any one of claims 2-4, characterized in that: The second purification component includes a second filtration device, which includes a nanofiltration membrane for separating the filtrate into a second clear liquid and a second dirty liquid.

7. The degumming liquid recovery system according to claim 6, characterized in that: The second filter includes a fifth outlet and a sixth outlet; The fifth outlet of the second filtration device is connected to the mixing assembly and is used to deliver the second clear liquid to the mixing assembly; The sixth outlet is used to discharge the second dirty fluid.

8. The degumming liquid recovery system according to claim 1, characterized in that, The preparation component includes an automatic liquid preparation device for preparing a degumming solution of a predetermined concentration and conveying it to the degumming tank.

9. The degumming liquid recovery system according to claim 1, characterized in that: The degumming tank, collection device, purification component, and mixing component are connected by pipes, and fluid is transferred under the action of overflow or pump.

10. The degumming liquid recovery system according to claim 1, characterized in that: At least one solenoid valve is provided on the first circulation loop and / or the second circulation loop for controlling fluid transmission.

Images