Cleaning equipment

Abstract

The utility model relates to cleaning equipment. The cleaning equipment comprises an acid pickling tank assembly, the acid pickling tank assembly comprises a plurality of acid pickling tanks arranged in sequence, each acid pickling tank is internally provided with an acid pickling solution, and at least one acid pickling tank is provided with an overflow port; and the overflow collecting tank is configured to be matched with the overflow port and connected with one of the pickling tanks, so that the pickling solution flowing out of the overflow port is collected and then conveyed to the pickling tank connected with the overflow port. According to the cleaning equipment, the pickling solution flowing out of the overflow port can be effectively collected, waste of the pickling solution is avoided, the environment is not affected, the collected pickling solution can be conveyed to the pickling tank connected with the overflow collecting tank, the pickling solution can be recycled, and the machining cost is remarkably reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of silicon wafer processing equipment, in particular to cleaning equipment. Background Art

[0002] Silicon wafers (also known as "silicon wafers") are one of the most fundamental materials used in semiconductor production. They are thin, high-purity slices made from single-crystal or polycrystalline silicon. Silicon wafers are typically round, with diameters ranging from a few millimeters to several hundred millimeters and thicknesses typically between 0.2 and 1.5 millimeters. Silicon wafers possess excellent electrical and optical properties and are widely used in integrated circuits, solar cells, communications equipment, and many other fields.

[0003] The cleaning process is a crucial step in the silicon wafer manufacturing process. During the manufacturing and processing of silicon wafers, the wafer surface is easily contaminated by various impurities and residues, such as grease, oxides, and dust. These impurities can degrade the electrical and optical properties of the silicon wafer. Therefore, specialized cleaning equipment is required to clean the silicon wafer to ensure surface smoothness and flatness, and improve the stability of its performance.

[0004] During the actual pickling process, the silicon wafers placed in the basket need to be immersed in the pickling tank to ensure a good pickling effect, which makes the pickling liquid in the pickling tank easily overflow. This not only wastes the pickling liquid, increases processing costs, but also pollutes the environment.

[0005] Therefore, this field needs a new technical solution to solve the above problems. Utility Model Content

[0006] In order to solve or, to a certain extent, improve the technical problem of pickling liquid easily overflowing in cleaning equipment in the prior art, the present invention provides a cleaning equipment. The cleaning equipment comprises: a pickling tank assembly, the pickling tank assembly comprising a plurality of pickling tanks arranged in sequence, each of which contains pickling liquid, and at least one of which is provided with an overflow port; and an overflow collection tank, the overflow collection tank being configured to match the overflow port and connected to one of the plurality of pickling tanks so as to collect the pickling liquid flowing out of the overflow port and transfer it to the connected pickling tank.

[0007] It will be understood by those skilled in the art that the cleaning equipment of the present invention includes a pickling tank assembly and an overflow collection tank. The pickling tank assembly includes a plurality of pickling tanks arranged in sequence, each of which is provided with pickling liquid so as to continuously pickle the silicon wafers, thereby obtaining a good pickling effect and improving the pickling efficiency. An overflow port is provided on at least one pickling tank so that the pickling liquid can flow out of the overflow port when the silicon wafer is immersed in the pickling tank. The overflow collection tank is configured to match the overflow port so that the pickling liquid flowing out of the overflow port can be effectively collected by the overflow collection tank, without causing waste of the pickling liquid and without causing any impact on the environment. More importantly, the overflow collection tank is connected to one of the plurality of pickling tanks so that the pickling liquid collected in the overflow collection tank can be transported to a suitable pickling tank, thereby realizing the reuse of the pickling liquid, improving the utilization efficiency of the pickling liquid, and significantly reducing processing costs.

[0008] In a preferred embodiment of the cleaning equipment, the multiple pickling tanks include a first pickling tank, a second pickling tank, and a third pickling tank, arranged sequentially along the pickling process. The overflow port is provided in the third pickling tank, and the overflow collection tank is connected to either the first or the second pickling tank. Because the third pickling tank is positioned at the end of the pickling process, while the first and second pickling tanks are positioned at the beginning, the pickling liquid overflowing from the third pickling tank is of higher purity. This liquid is collected in the overflow collection tank and then transferred to the first or second pickling tank, achieving a better pickling effect.

[0009] In a preferred embodiment of the cleaning equipment, the pickling solution in the first, second, and third pickling tanks is the same type. This arrangement ensures uniform and consistent removal of contaminants from the silicon wafer surface, helps control the reaction process, avoids damage to the silicon wafer caused by using different types of pickling solution, and improves the stability of silicon wafer processing. Furthermore, using the same type of pickling solution reduces operational complexity, optimizes inventory management, and reduces procurement costs.

[0010] In the preferred technical solution of the cleaning equipment, the concentrations of the pickling solution in the first, second, and third pickling tanks are C1, C2, and C3, respectively, where C1 ≤ C2 ≤ C3. This arrangement ensures effective pickling, removes stubborn contaminants, and ensures a smooth and controllable pickling process.

[0011] In the preferred technical solution of the cleaning equipment, the pickling liquid is one or more of hydrofluoric acid, hydrochloric acid, sulfuric acid, and nitric acid. Through the above configuration, the types of pickling liquids can be enriched to meet the pickling needs of silicon wafers under different working conditions.

[0012] In a preferred embodiment of the cleaning apparatus, the pickling tank has a first end and a second end that are opposed to each other along its length, and the overflow port is disposed at the first and / or second ends of the corresponding pickling tank. This arrangement positions the overflow port on a short side of the pickling tank, facilitating the collection of overflowing pickling liquid.

[0013] In a preferred technical solution of the cleaning equipment, the overflow collecting trough is no higher than the overflow port. The overflow collecting trough is configured to be no higher than the overflow port so that the overflowing pickling liquid can be effectively collected by the overflowing pickling liquid to avoid waste of the pickling liquid.

[0014] In a preferred embodiment of the cleaning apparatus, a collection chamber is provided within the overflow collection tank. The collection chamber is fluidically connected to the connected pickling tank, and the cross-section of the collection chamber gradually decreases vertically downward. This arrangement allows the collection chamber to have a "wide at the top and narrow at the bottom" structure, facilitating the collection of pickling liquid.

[0015] In a preferred embodiment of the cleaning apparatus, a conductivity meter is provided within the overflow collection tank to detect the concentration of the collected pickling solution. The conductivity meter can accurately detect the concentration of the pickling solution collected within the overflow collection tank, facilitating adjustment of the pickling solution flow rate to better meet pickling requirements.

[0016] In a preferred technical solution of the cleaning equipment, a controller is further provided in the overflow collection tank to control the connection and disconnection between the overflow collection tank and the corresponding pickling tank. This arrangement allows for precise control of the connection and disconnection between the overflow collection tank and the corresponding pickling tank, improving control accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which:

[0018] Figure 1 It is a structural schematic diagram of an embodiment of the cleaning device of the utility model;

[0019] Figure 2 It is a structural schematic diagram of an embodiment of a pickling tank and an overflow collection tank in the cleaning equipment of the present invention.

[0020] 100. Cleaning equipment; 110. Alkaline washing tank assembly; 111. Alkaline washing tank; 112. Second water washing tank; 120. First water washing tank; 130. Pickling tank assembly; 131. First pickling tank; 132. Second pickling tank; 133. Third pickling tank; 133a. First end; 133b. Second end; 1331. Overflow port; 140. Overflow collecting tank; 141. Collection chamber; 142. Drain port; 143. First controller; 150. Rehydration tank assembly; 151. Rehydration tank; 152. Second controller; 160. Third water washing tank; 170. Dehydration tank. DETAILED DESCRIPTION

[0021] The preferred embodiments of the present invention are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are only used to explain the technical principles of the present invention and are not intended to limit the scope of protection of the present invention.

[0022] It should be noted that, in the description of the present invention, terms such as "up", "down", "left", "right", "front", "back", "inside", and "outside" indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings. This is merely for the convenience of description and does not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it cannot be understood as a limitation on the present invention.

[0023] Furthermore, it should be noted that, in the description of this utility model, unless otherwise expressly specified or limited, the terms "installed," "set," and "connected" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0024] To solve or, to a certain extent, improve the technical problem of pickling liquid easily overflowing in conventional cleaning equipment, the present invention provides a cleaning equipment 100. The cleaning equipment 100 comprises: a pickling tank assembly 130 comprising a plurality of pickling tanks arranged in sequence, each containing pickling liquid, and at least one of which is provided with an overflow port 1331; and an overflow collection tank 140 configured to mate with the overflow port 1331 and connected to one of the plurality of pickling tanks, so as to collect the pickling liquid flowing out of the overflow port 1331 and deliver it to the connected pickling tank.

[0025] Figure 1 It is a structural schematic diagram of an embodiment of the cleaning device of the utility model; Figure 2This is a schematic diagram of the structure of an embodiment of the pickling tank and overflow collection tank in the cleaning equipment of the utility model. Figure 1 and Figure 2 As shown, in one or more embodiments, the cleaning apparatus 100 of the present invention includes a pickling tank assembly 130 and an overflow collection tank 140. The pickling tank assembly 130 includes a plurality of pickling tanks arranged in sequence. Each pickling tank is provided with pickling liquid to continuously and effectively pickle the silicon wafers. An overflow port 1331 is provided on at least one pickling tank, allowing the pickling liquid to be discharged from the overflow port 1331 while the silicon wafer is immersed in the pickling tank. The overflow collection tank 140 is coupled to the overflow port 1331 to collect the pickling liquid flowing out of the overflow port 1331. The overflow collection tank 140 is connected to one of the plurality of pickling tanks to transfer the collected pickling liquid to the pickling tank connected to the overflow collection tank 140. Therefore, the cleaning apparatus 100 of the present invention can effectively collect the pickling liquid without wasting the pickling liquid or causing any environmental impact. It can also achieve the reuse of the pickling liquid, thereby improving the utilization efficiency of the pickling liquid and significantly reducing processing costs.

[0026] like Figure 1 As shown, in one or more embodiments, the plurality of pickling tanks includes a first pickling tank 131, a second pickling tank 132, and a third pickling tank 133, arranged sequentially along the pickling process. The third pickling tank 133 is provided with an overflow port 1331. An overflow collection tank 140 mates with the overflow port 1331 on the third pickling tank 133 and is connected to the first pickling tank 131 to collect the pickling liquid overflowing from the third pickling tank 133 and timely deliver it to the first pickling tank 131. Alternatively, the number of pickling tanks may be set to another suitable number less than or equal to three, such as two or four. Alternatively, the overflow port 1331 may be provided in the first pickling tank 131 or the second pickling tank 132. Furthermore, the overflow port 1331 may be provided in multiple pickling tanks, for example, in each of the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133. Alternatively, the overflow collecting tank 140 may also be configured to be connected to the second acid washing tank 132 or the third acid washing tank 133 .

[0027] In one or more embodiments, the pickling solution in the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133 is one or more of hydrofluoric acid, hydrochloric acid, sulfuric acid, and nitric acid. For example, the pickling solution can be a mixture of hydrofluoric acid and hydrochloric acid. This configuration allows for a variety of pickling solution types to meet the pickling needs of silicon wafers under different operating conditions.

[0028] In one or more embodiments, the pickling solution in the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133 is of the same type. For example, the pickling solution in the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133 is a mixture of hydrofluoric acid and hydrochloric acid. This ensures uniformity and consistency in the removal of contaminants from the silicon wafer surface, helps control the reaction process, avoids damage to the silicon wafer caused by the use of different types of pickling solution, and improves the stability of silicon wafer processing. In addition, using the same type of pickling solution can also reduce operational difficulty, optimize inventory management, and reduce procurement costs.

[0029] In one or more embodiments, the concentrations of the pickling solutions in the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133 are C1, C2, and C3, respectively, where C1≤C2≤C3. By setting the concentrations of the pickling solutions in the first pickling tank 131, the second pickling tank 132, and the third pickling tank 133 to be the same or gradually increasing along the pickling process, the pickling effect can be ensured, stubborn contaminants can be effectively removed, and a smooth and controllable pickling process can be ensured. It should be noted that the specific values ​​of C1, C2, and C3 can be adjusted according to the type of pickling solution and the actual needs of pickling.

[0030] like Figure 2 As shown, in one or more embodiments, the third pickling tank 133 has a substantially rectangular parallelepiped shape and has an upward opening. The third pickling tank 133 has a plurality of Figure 2 The first end 133a and the second end 133b are opposite to each other in the direction shown, that is, the left and right directions. Figure 2 In the orientation shown, the first end 133a is the left end of the third pickling tank 133, and the second end 133b is the right end of the third pickling tank 133. The overflow port 1331 is arranged on the second end 133b of the third pickling tank 133. Alternatively, the overflow port 1331 can also be arranged on the first end 133a of the third pickling tank 133. Further, the overflow port 1331 can also be arranged on the first end 133a and the second end 133b of the third pickling tank 133 at the same time. Through the above-mentioned arrangement, the overflow port 1331 is positioned on the opposite short side of the third pickling tank 133, which is convenient for collecting the overflowed pickling liquid. In one or more embodiments, the overflow port 1331 is arranged along the width direction of the third pickling tank 133 (based on Figure 2 The overflow port 1331 extends in the direction shown, i.e., the front-to-back direction, and is configured as a continuous notch. Alternatively, the overflow port 1331 may be configured as a plurality of through holes spaced apart from one another along the width of the third pickling tank 133. It will be appreciated that while the silicon wafer is immersed in the third pickling tank 133, the level of the pickling solution in the third pickling tank 133 will gradually rise, and the pickling solution will be smoothly discharged from the overflow port 1331 without overflowing from other edges of the third pickling tank 133.

[0031] Continue to see Figure 2 The overflow collection trough 140 is arranged on one side of the third pickling tank 133 near the second end 133b. The overflow collection trough 140 has a substantially rectangular parallelepiped shape and has an upward opening. In one or more embodiments, the width of the overflow collection trough 140 is equal to or greater than the width of the third pickling tank 133 so as to effectively collect the pickling liquid flowing out of the overflow port 1331. In one or more embodiments, the height of the overflow collection trough 140 is no higher than the height of the overflow port 1331, so that the overflow collection trough 140 can effectively collect the overflowed pickling liquid and avoid waste of the pickling liquid.

[0032] Continue to see Figure 2 In one or more embodiments, a collection chamber 141 is provided in the overflow collection tank 140. The collection chamber 141 can be fluidically connected to the connected third pickling tank 133. The cross-section of the collection chamber 141 is configured to gradually decrease in the vertical downward direction. Through the above-mentioned configuration, the collection chamber 141 has a "wide at the top and narrow at the bottom" structure, which is convenient for collecting pickling liquid. In one or more embodiments, a drain port 142 is provided at the bottom of the collection chamber 141, and the drain port 142 is connected to the corresponding pickling tank (for example, the first pickling tank 131) through a pipeline. In one or more embodiments, a controller is also provided in the overflow collection tank 140. The controller is a first controller 143, which can communicate with a control valve (not shown in the figure) between the overflow collection tank 140 and the first pickling tank 131 to control the on-off between the overflow collection tank 140 and the corresponding pickling tank.

[0033] In one or more embodiments, a conductivity tester (not shown) is further provided within the overflow collection tank 140 to detect the concentration of the collected pickling solution. The conductivity tester can accurately detect the concentration of the pickling solution collected within the overflow collection tank 140, facilitating adjustment of the pickling solution flow rate to better meet pickling requirements.

[0034] like Figure 1 As shown, in one or more embodiments, the cleaning equipment 100 of the present invention further includes a rehydration tank assembly 150. The rehydration tank assembly 150 includes a rehydration tank 151 connected to a plurality of pickling tanks and a second controller 152. The rehydration tank 151 is connected to each pickling tank through a suitable pipeline. A control valve that can be opened and closed is provided on each pipeline (not shown in the figure). The second controller 152 forms a communication connection with the control valve to flexibly control the opening and closing of each corresponding control valve, thereby conveniently replenishing the pickling liquid in the rehydration tank 151 into the pickling tank, ensuring that the pickling liquid has a moderate concentration, and ensuring the pickling effect and pickling efficiency.

[0035] like Figure 1As shown, in one or more embodiments, the cleaning equipment 100 of the present invention further includes an alkaline washing tank assembly 110. The alkaline washing tank assembly 110 is arranged upstream of the acid washing tank assembly 130. The alkaline washing tank assembly 110 includes a plurality of alkaline washing tanks 111 arranged in sequence. Each alkaline washing tank 111 contains an alkaline washing solution of appropriate concentration. The alkaline washing solution may be, but is not limited to, ammonium hydroxide, sodium hydroxide, alkaline hydrogen peroxide washing solution, etc. The type of alkaline washing solution in each alkaline washing tank 111 may be the same or different. In addition, the concentration of the alkaline washing solution in each alkaline washing tank 111 may be adjusted according to actual needs. The provision of multiple alkaline washing tanks 111 can effectively perform alkaline washing on silicon wafers. It should be noted that the number of alkaline washing tanks 111 may be 6, 7, 8 or other suitable numbers.

[0036] like Figure 1 As shown, in one or more embodiments, a first water washing tank 120 is provided between the plurality of alkaline washing tanks 111 and the acid washing tank assembly 130. Deionized water or other suitable cleaning liquid is provided in the first water washing tank 120 to effectively remove the alkaline washing liquid remaining on the surface of the silicon wafer, ensuring that the silicon wafer has a good acid washing effect in the subsequent acid washing tank assembly 130.

[0037] like Figure 1 As shown, in one or more embodiments, at least one second water washing tank 112 is disposed between the multiple alkali washing tanks 111. For example, two second water washing tanks 112 are disposed between six alkali washing tanks 111. Furthermore, these two second water washing tanks 112 can be evenly spaced between the six alkali washing tanks 111. That is, the alkali washing tanks 111 and second water washing tanks 112 are arranged in a "alkali washing tank 111 - alkali washing tank 111 - second water washing tank 112 - alkali washing tank 111 - alkali washing tank 111 - second water washing tank 112 - alkali washing tank 111 - alkali washing tank 111." The second water washing tanks 112 are filled with deionized water or other suitable cleaning fluid. The provision of the second water washing tanks 112 can promptly remove the alkali washing fluid and other contaminants from the silicon wafer surface, preventing them from impacting subsequent processes, ensuring the continuity of the cleaning process, and improving cleaning efficiency. Alternatively, the number and placement of the second water washing tanks 112 can be adjusted according to actual needs.

[0038] like Figure 1As shown, in one or more embodiments, the cleaning equipment 100 of the present invention further includes a dewatering tank 170. The dewatering tank 170 is arranged downstream of the pickling tank assembly 130, and a third water washing tank 160 is provided between the dewatering tank 170 and the pickling tank assembly 130. Deionized water or other suitable cleaning liquid is provided in the third water washing tank 160. The provision of the third water washing tank 160 can effectively remove the pickling liquid remaining on the surface of the silicon wafer and ensure the cleanliness of the silicon wafer. The dewatering tank 170 can use a suitable drying method (such as nitrogen drying or hollow drying, etc.) to thoroughly dry the cleaned silicon wafer to remove residual moisture on the surface of the silicon wafer and ensure the quality and performance of the silicon wafer in subsequent processes (such as photolithography, etching, etc.).

[0039] Thus far, the technical solutions of the present invention have been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art may make equivalent changes or substitutions to the relevant technical features, and the technical solutions after such changes or substitutions will fall within the scope of protection of the present invention.

Claims

1. A cleaning device, characterized in that: The cleaning equipment comprises: A pickling tank assembly, the pickling tank assembly comprising a plurality of pickling tanks arranged in sequence, each of the pickling tanks being provided with a pickling liquid, and at least one of the pickling tanks being provided with an overflow port; and An overflow collecting trough is configured to match the overflow port and be connected to one of the plurality of pickling tanks, so as to collect the pickling liquid flowing out of the overflow port and then transport it to the pickling tank connected thereto.

2. The cleaning device according to claim 1, characterized in that The plurality of pickling tanks include a first pickling tank, a second pickling tank and a third pickling tank sequentially arranged along the pickling process, and the overflow port is provided on the third pickling tank; and The overflow collecting tank is configured to be connected to the first pickling tank or the second pickling tank.

3. The cleaning device according to claim 2, characterized in that The pickling solutions in the first pickling tank, the second pickling tank, and the third pickling tank are of the same type.

4. The cleaning device according to claim 3, characterized in that The concentrations of the pickling solutions in the first pickling tank, the second pickling tank, and the third pickling tank are C1, C2, and C3, respectively, wherein C1≤C2≤C3.

5. The cleaning device according to claim 3, characterized in that: The pickling solution is one or more of hydrofluoric acid, hydrochloric acid, sulfuric acid and nitric acid.

6. The cleaning device according to claim 1, characterized in that The pickling tank has a first end and a second end opposite to each other along a length direction thereof, wherein the overflow port is arranged on the first end and / or the second end of the corresponding pickling tank.

7. The cleaning device according to claim 1, characterized in that The height of the overflow collecting trough is not higher than the height of the overflow port.

8. The cleaning device according to claim 1, characterized in that A collecting chamber is provided in the overflow collecting tank, and the collecting chamber can be in fluid communication with the connected pickling tank, wherein the cross section of the collecting chamber gradually decreases in a vertical downward direction.

9. The cleaning device according to claim 1, characterized in that A conductivity tester is also provided in the overflow collection tank to detect the concentration of the collected pickling liquid.

10. The cleaning device according to claim 1, characterized in that A controller is also provided in the overflow collecting tank to control the connection and disconnection between the overflow collecting tank and the corresponding pickling tank.

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