Pickling device and alkali polishing equipment

Abstract

The utility model relates to a pickling device and alkali polishing equipment. The pickling device comprises a pickling tank and a first rinsing tank; a first overflow part is arranged in the pickling tank, the interior of the pickling tank is divided into a first reaction tank and a first overflow tank by the first overflow part, the first washing tank is communicated with the first overflow tank, and the first washing tank is used for receiving a pickling solution overflowing from the first reaction tank to the first overflow tank. According to the pickling device, the utilization rate of pickling liquid can be increased, consumption of the pickling liquid in the cleaning process is reduced, and then the cleaning cost is reduced. The alkali polishing equipment comprises the pickling device.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a pickling device and an alkali polishing device. Background Art

[0002] In the process of preparing solar cells, it is necessary to use an acid cleaning device to clean silicon wafers. In the traditional cleaning process, as the reaction proceeds, after the acid cleaning liquid is added to the acid cleaning tank, the excess acid cleaning liquid in the acid cleaning tank is often directly discharged. This will increase the consumption of the acid cleaning liquid and increase the cleaning cost. Utility Model Content

[0003] Based on this, it is necessary to provide a pickling device and alkali polishing equipment that can reduce cleaning costs.

[0004] A pickling device comprises a pickling tank and a first water washing tank; a first overflow piece is provided in the pickling tank, the first overflow piece divides the interior of the pickling tank into a first reaction tank and a first overflow tank, the first water washing tank is connected to the first overflow tank, and the first water washing tank is used to receive the pickling liquid overflowing from the first reaction tank to the first overflow tank.

[0005] In the above pickling device, the pickling tank and the first water washing tank are arranged so that the first water washing tank is connected to the first overflow tank. When the pickling device is used to pickle the silicon wafer, the silicon wafer can be placed in the first reaction tank of the pickling tank for reaction. During the reaction, as the reaction proceeds and the pickling liquid is added, the pickling liquid can overflow from the first reaction tank to the first overflow tank and then enter the first water washing tank. The pickling liquid entering the first water washing tank can be reused, which can improve the utilization rate of the pickling liquid, reduce the consumption of the pickling liquid during the cleaning process, and thus reduce the cleaning cost.

[0006] In some embodiments, a second overflow member is provided in the first water washing tank, and the second overflow member divides the interior of the first water washing tank into a second reaction tank and a second overflow tank, and the second reaction tank is connected to the first overflow tank.

[0007] In some embodiments, the pickling device further includes a temporary storage tank, which is connected to the first overflow tank and is also connected to the first water washing tank, and is used to temporarily store the pickling liquid overflowing from the first reaction tank to the first overflow tank.

[0008] In some embodiments, the liquid outlet of the first overflow trough is located at the bottom of the first overflow trough, and the temporary storage tank is located below the pickling tank so that the pickling liquid enters the temporary storage tank under the action of gravity.

[0009] In some embodiments, the pickling device further includes a pressure pump, which is connected between the temporary storage tank and the first water washing tank, and is used to transfer the pickling liquid in the temporary storage tank to the first water washing tank.

[0010] An alkali polishing device comprises an alkali polishing tank and a pickling device which are arranged in sequence; the pickling tank is located between the alkali polishing tank and the first water washing tank.

[0011] In some embodiments, the alkali polishing equipment further includes a pulling tank; the pulling tank and the first water washing tank are located on the same side of the pickling tank, and the pulling tank is farther away from the pickling tank than the first water washing tank.

[0012] In some embodiments, the alkali polishing equipment further includes a drying tank; the drying tank and the pulling tank are located on the same side of the first water washing tank, and the drying tank is farther away from the first water washing tank than the pulling tank.

[0013] In some embodiments, the alkali polishing equipment also includes a first cleaning tank and a second cleaning tank; the first cleaning tank and the alkali polishing tank are located on the same side of the pickling tank, and the first cleaning tank is farther away from the pickling tank than the alkali polishing tank; the second cleaning tank is located between the alkali polishing tank and the pickling tank.

[0014] In some embodiments, the alkali polishing equipment further includes a second water washing tank; the second water washing tank is disposed between the alkali polishing tank and the acid washing tank. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of a pickling device in one embodiment of the present application.

[0016] Figure 2 This is a schematic diagram of the structure of the alkali polishing equipment in one embodiment of the present application.

[0017] Description of the markings in the figure:

[0018] 10. Pickling device; 101. Pickling tank; 1011. First overflow piece; 1012. First reaction tank; 1013. First overflow tank; 102. First water washing tank; 1021. Second overflow piece; 1022. Second reaction tank; 1023. Second overflow tank; 103. Temporary storage tank; 104. Pressure pump; 105. Pipeline; 20. Alkali polishing equipment; 201. Alkali polishing tank; 202. Pulling tank; 203. First cleaning tank; 204. Second cleaning tank; 205. Drying tank; 206. Second water washing tank. DETAILED DESCRIPTION

[0019] In order to make the above-mentioned purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. In the following description, many specific details are set forth to facilitate a full understanding of the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without violating the connotation of the present application, so the present application is not limited by the specific embodiments disclosed below.

[0020] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application 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 a limitation on the present application.

[0021] 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 this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0022] In this application, 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 this application can be understood according to specific circumstances.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0024] See also Figure 1In one embodiment of the present application, a pickling device 10 is provided. The pickling device 10 includes a pickling tank 101 and a first water washing tank 102. A first overflow member 1011 is provided in the pickling tank 101, and the first overflow member 1011 divides the interior of the pickling tank 101 into a first reaction tank 1012 and a first overflow tank 1013. The first water washing tank 102 is connected to the first overflow tank 1013, and the first water washing tank 102 is used to receive the pickling liquid overflowing from the first reaction tank 1012 to the first overflow tank 1013.

[0025] In the pickling device 10 of this embodiment, the pickling tank 101 and the first water washing tank 102 are arranged so that the first water washing tank 102 is connected to the first overflow tank 1013. When the pickling device 10 is used to pickle the silicon wafer, the silicon wafer can be placed in the first reaction tank 1012 of the pickling tank 101 for reaction. During the reaction process, as the reaction proceeds and the pickling liquid is added, the pickling liquid can overflow from the first reaction tank 1012 to the first overflow tank 1013, and then enter the first water washing tank 102. The pickling liquid entering the first water washing tank 102 can be reused, which can improve the utilization rate of the pickling liquid, reduce the consumption of the pickling liquid during the cleaning process, and thus reduce the cleaning cost.

[0026] Furthermore, in the pickling device 10 of this embodiment, since part of the pickling liquid enters the first water washing tank 102, the liquid in the first water washing tank 102 can have a certain acidity. When the silicon wafer is washed in the first water washing tank 102, the hydrophobicity of the silicon wafer surface can be improved, which is conducive to reducing the adhesion of water on the silicon wafer surface, and further conducive to promoting the dehydration of the silicon wafer surface, reducing the watermark residue on the silicon wafer surface, and improving the cleaning effect.

[0027] It is understandable that when the pickling device 10 in the present embodiment is used to pickle the silicon wafer, the pickling solution in the pickling tank 101 includes hydrofluoric acid. When the silicon wafer is cleaned, hydrofluoric acid is continuously consumed, and hydrofluoric acid needs to be regularly added so that the concentration of hydrofluoric acid in the pickling tank 101 meets the cleaning requirements. After the silicon wafer is cleaned by the pickling tank 101, it enters the first water washing tank 102. During the cleaning process of the first water washing tank 102, the first water washing tank 102 can be replenished with water so that the water washing in the first water washing tank 102 meets the cleaning requirements. Optionally, the initial composition of the pickling solution in the pickling tank 101 is 24L of hydrofluoric acid and 316L of water. The volume of each additional hydrofluoric acid is 30mL. The replenishment cycle of hydrofluoric acid is 1200 batches of silicon wafers.

[0028] It can also be understood that when the pickling device 10 in this embodiment is used to clean silicon wafers, a portion of the pickling liquid will enter the first water washing tank 102, which can make the washing liquid in the first water washing tank 102 weakly acidic, which is beneficial to reduce watermarks and dirt residues on the surface of the silicon wafer during the cleaning process, thereby helping to improve the cleaning effect.

[0029] In some embodiments, a second overflow member 1021 is provided in the first water washing tank 102. The second overflow member 1021 divides the interior of the first water washing tank 102 into a second reaction tank 1022 and a second overflow tank 1023. The second reaction tank 1022 is connected to the first overflow tank 1013, and the second reaction tank 1022 is used to receive the acid washing liquid overflowing from the first reaction tank 1012 to the first overflow tank 1013. The second overflow member 1021 is provided in the first water washing tank 102, so as to control the washing liquid overflowing from the second reaction tank 1022 to the second overflow tank 1023, so as to maintain the stability of the washing liquid in the second reaction tank 1022. Optionally, during the cleaning process, the overflow rate of the washing liquid in the second reaction tank 1022 to overflow the second overflow tank 1023 is controlled to be 300L / h.

[0030] In some embodiments, the pickling device 10 further includes a temporary storage tank 103. The temporary storage tank 103 is connected to the first overflow tank 1013, and the temporary storage tank 103 is also connected to the first water washing tank 102. The temporary storage tank 103 is used to temporarily store the pickling liquid overflowing from the first reaction tank 1012 to the first overflow tank 1013. The provision of the temporary storage tank 103 can temporarily store the pickling liquid, which is convenient for controlling the flow of the pickling liquid entering the first water washing tank 102 during the cleaning process.

[0031] It is understandable that the pickling device 10 further includes a pipeline 105. The temporary storage tank 103 is connected to the first overflow tank 1013 through the pipeline 105. Through the arrangement of the pipeline 105, the pickling liquid can enter the temporary storage tank 103 from the first overflow tank 1013 more stably.

[0032] In some embodiments, the liquid outlet of the first overflow trough 1013 is located at the bottom of the first overflow trough 1013, and the temporary storage tank 103 is located below the pickling tank 101 so that the pickling liquid enters the temporary storage tank 103 under the action of gravity. In this way, the pickling liquid in the first overflow trough 1013 can enter the temporary storage tank 103 without the need for additional power, which is conducive to reducing the energy consumption of the cleaning process. At the same time, the liquid outlet of the first overflow trough 1013 is located at the bottom of the first overflow trough 1013, and the temporary storage tank 103 is located below the pickling tank 101. The design is simple, which is convenient for installing and arranging the pickling tank 101 and the temporary storage tank 103.

[0033] In some embodiments, the pickling device 10 further includes a pressure pump 104, which is connected between the temporary storage tank 103 and the first water washing tank 102, and the pressure pump 104 is used to transfer the pickling solution in the temporary storage tank 103 to the first water washing tank 102. By setting the pressure pump 104, the pickling solution in the temporary storage tank 103 can be conveniently transferred to the first water washing tank 102, and the pickling solution is transferred between the temporary storage tank 103 and the first water washing tank 102. Optionally, the pressure pump 104 is a circulation pump. Optionally, the temporary storage tank 103 and the first water washing tank 102 are connected by a pipeline 105, and the pressure pump 104 is arranged on the pipeline 105.

[0034] See also Figure 2 In another embodiment of the present application, an alkali polishing device 20 is provided. The alkali polishing device 20 includes an alkali polishing tank 201 and a pickling device 10 which are arranged in sequence. The pickling tank 101 is located between the alkali polishing tank 201 and the first water washing tank 102. The alkali polishing device 20 of this embodiment can obtain a good alkali polishing effect when alkali polishing the silicon wafer.

[0035] In some embodiments, the alkali polishing device 20 further includes a pulling tank 202. The pulling tank 202 and the first water washing tank 102 are located on the same side of the pickling tank 101, and the pulling tank 202 is further away from the pickling tank 101 than the first water washing tank 102. The setting of the pulling tank 202 can preliminarily remove moisture from the surface of the silicon wafer, reducing the risk of adhesion between adjacent silicon wafers.

[0036] It is understandable that the pulling tank 202 is a slow pulling tank, and a conventional slow pulling tank can be used. The alkali polishing tank 201 can be a conventional alkali polishing tank.

[0037] In some embodiments, there are multiple alkali polishing tanks 201, and the multiple alkali polishing tanks 201 are arranged in sequence. Figure 2 In the illustrated embodiment, there are two alkali polishing tanks 201. It is understandable that there may be three, four, five, etc. alkali polishing tanks 201.

[0038] In some embodiments, the alkali polishing equipment 20 further includes a first cleaning tank 203 and a second cleaning tank 204. The first cleaning tank 203 and the alkali polishing tank 201 are located on the same side of the pickling tank 101, and the first cleaning tank 203 is further away from the pickling tank 101 than the alkali polishing tank 201. The second cleaning tank 204 is located between the alkali polishing tank 201 and the pickling tank 101. By setting the first cleaning tank 203 and the second cleaning tank 204, the cleaning effect can be further improved. It can be understood that the first cleaning tank 203 can be a front cleaning tank, and the second cleaning tank 204 can be a rear cleaning tank.

[0039] In some embodiments, the alkali polishing device 20 further includes a drying tank 205. The drying tank 205 and the pulling tank 202 are located on the same side of the first water washing tank 102, and the drying tank 205 is further away from the first water washing tank 102 than the pulling tank 202. The silicon wafer after cleaning can be dried by setting the drying tank 205. Optionally, there are multiple drying tanks 205. Multiple drying tanks 205 are arranged in sequence. Further optionally, as Figure 2 As shown, there are four drying slots 205. It is understandable that the number of drying slots 205 can also be one, two, three, five, six, etc.

[0040] In some embodiments, the alkali polishing equipment 20 further includes a second water washing tank 206. The second water washing tank 206 is disposed between the alkali polishing tank 201 and the acid washing tank 101. The second water washing tank 206 can reduce the mixing of cleaning liquids between different tanks, thereby further improving the cleaning effect.

[0041] It is understood that a second water washing tank 206 is provided between the first cleaning tank 203 and the alkali polishing tank 201. A second water washing tank 206 is provided between the alkali polishing tank 201 and the second cleaning tank 204. A second water washing tank 206 is provided between the second cleaning tank 204 and the pickling tank 101.

[0042] Example 1

[0043] This embodiment adopts Figure 2 The alkaline polishing equipment shown in the figure performs alkaline polishing on silicon wafers. Among them, the initial hydrofluoric acid dosage and the hydrofluoric acid supplementation dosage of the pickling solution in the pickling tank are shown in Table 1. The unit consumption of hydrofluoric acid and the life batch of the pickling solution are shown in Table 1. The proportion of dirt on the surface appearance of the silicon wafer is shown in Table 1. The silicon wafer is prepared into a PERC cell (Passivated Emitter and Rear Cell, i.e., a passivated emitter and a rear cell), and the EL yield (Electroluminescent, i.e., electroluminescent yield) and efficiency of the cell are shown in Table 1.

[0044] Comparative Example 1

[0045] Compared with Example 1, the difference of this comparative example is that there is no connection between the pickling tank and the first water washing tank. The pickling solution in the pickling tank is directly discharged. Among them, the initial hydrofluoric acid dosage and the hydrofluoric acid supplementation amount of the pickling solution in the pickling tank are shown in Table 1. The unit consumption of hydrofluoric acid and the life batch of the pickling solution are shown in Table 1. The proportion of dirt on the front appearance of the silicon wafer is shown in Table 1. The silicon wafer is prepared into a PERC battery, and the EL yield and efficiency of the battery are shown in Table 1.

[0046] Table 1

[0047]

[0048] It can be seen from Table 1 that, based on a lower amount of hydrogen fluoride added, Example 1 achieved lower hydrogen fluoride unit consumption, higher life batches, and lower dirt ratio, and the EL yield and efficiency were both at a high level.

[0049] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims, and the specification and drawings may be used to interpret the contents of the claims.

Claims

1. A pickling device (10), It is characterized in that The invention comprises a pickling tank (101) and a first water washing tank (102); a first overflow part (1011) is provided in the pickling tank (101); the first overflow part (1011) divides the interior of the pickling tank (101) into a first reaction tank (1012) and a first overflow tank (1013); the first water washing tank (102) is connected to the first overflow tank (1013); the first water washing tank (102) is used to receive pickling liquid overflowing from the first reaction tank (1012) to the first overflow tank (1013).

2. The pickling device (10) according to claim 1, It is characterized in that A second overflow member (1021) is provided in the first water washing tank (102), and the second overflow member (1021) divides the interior of the first water washing tank (102) into a second reaction tank (1022) and a second overflow tank (1023), and the second reaction tank (1022) is connected to the first overflow tank (1013).

3. The pickling device (10) according to any one of claims 1 to 2, It is characterized in that The pickling device (10) further comprises a temporary storage tank (103), wherein the temporary storage tank (103) is connected to the first overflow tank (1013), and the temporary storage tank (103) is also connected to the first water washing tank (102), and the temporary storage tank (103) is used to temporarily store the pickling liquid overflowing from the first reaction tank (1012) to the first overflow tank (1013).

4. The pickling device (10) according to claim 3, It is characterized in that The liquid outlet of the first overflow trough (1013) is located at the bottom of the first overflow trough (1013), and the temporary storage trough (103) is located below the pickling trough (101) so as to allow the pickling liquid to enter the temporary storage trough (103) under the action of gravity.

5. The pickling device (10) according to claim 4, It is characterized in that The pickling device (10) further comprises a pressure pump (104), wherein the pressure pump (104) is connected between the temporary storage tank (103) and the first water washing tank (102), and the pressure pump (104) is used to transfer the pickling liquid in the temporary storage tank (103) to the first water washing tank (102).

6. An alkali polishing device (20), It is characterized in that It comprises an alkali polishing tank (201) and a pickling device (10) according to any one of claims 1 to 5, which are arranged in sequence; the pickling tank (101) is located between the alkali polishing tank (201) and the first water washing tank (102).

7. The alkali polishing device (20) according to claim 6, It is characterized in that The alkali polishing equipment (20) further includes a pulling tank (202); the pulling tank (202) and the first water washing tank (102) are located on the same side of the pickling tank (101), and the pulling tank (202) is farther away from the pickling tank (101) than the first water washing tank (102).

8. The alkali polishing device (20) according to claim 7, It is characterized in that The alkali polishing equipment (20) further includes a drying tank (205); the drying tank (205) and the pulling tank (202) are located on the same side of the first water washing tank (102), and the drying tank (205) is farther away from the first water washing tank (102) than the pulling tank (202).

9. The alkali polishing device (20) according to claim 6, It is characterized in that The alkali polishing equipment (20) further comprises a first cleaning tank (203) and a second cleaning tank (204); the first cleaning tank (203) and the alkali polishing tank (201) are located on the same side of the pickling tank (101), and the first cleaning tank (203) is farther away from the pickling tank (101) than the alkali polishing tank (201); and the second cleaning tank (204) is located between the alkali polishing tank (201) and the pickling tank (101).

10. The alkali polishing equipment (20) according to any one of claims 6 to 9, It is characterized in that The alkali polishing equipment (20) further comprises a second water washing tank (206); the second water washing tank (206) is arranged between the alkali polishing tank (201) and the acid washing tank (101).

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