Chemical treatment tank and photovoltaic wet treatment equipment

Abstract

The utility model discloses a chemical treatment tank and photovoltaic wet process treatment equipment, the chemical treatment tank comprises an outer tank body and an inner tank body, and the inner tank bottom wall of the inner tank body obliquely extends downwards along a first direction. When the photovoltaic wet processing equipment is used for carrying out chemical processing on a to-be-processed part, the inner tank body contains liquid medicine and overflows into the outer tank body, and new liquid medicine is supplemented into the inner tank body at the upstream of the first direction, so that the liquid medicine can flow in a tank cavity of the inner tank along the first direction; meanwhile, the to-be-treated part is conveyed to pass through the chemical treatment tank in the second direction opposite to the first direction, so that the to-be-treated part is in contact with old liquid medicine firstly and then is in contact with new liquid medicine, the surface treatment effect of the to-be-treated part can be improved, and the probability that residues generated by reaction are brought into a subsequent tank body is reduced.

Description

Technical Field

[0001] The utility model relates to the field of photovoltaic cell manufacturing, in particular to a chemical treatment tank and photovoltaic wet treatment equipment. Background Art

[0002] The photovoltaic diffusion process is one of the important links in the manufacturing process of solar cells. It forms a doped layer on the surface of the silicon wafer to make it a semiconductor material with a pn structure.

[0003] Due to the influx of oxygen during the diffusion process, a SiO2 layer is often formed on the surface of the silicon wafer. At high temperatures, POCl3 and O2 form P2O5. Some P atoms enter Si to replace some Si atoms on the lattice to form n-type semiconductors, while some remain in SiO2 to form phosphosilicate glass (PSG). The presence of phosphosilicate glass makes the surface of the silicon wafer susceptible to moisture in the air, resulting in a decrease in current and power attenuation, causing a "dead layer" to form in this part of the cell. The presence of the "dead layer" greatly increases the recombination of electrons in the emission region, which will lead to a decrease in the minority carrier lifetime, thereby reducing V oc and I sc .

[0004] The presence of phosphosilicate glass causes color difference after the PECVD (plasma enhanced chemical vapor deposition) process. x N y It is prone to falling off, reducing the conversion efficiency of the battery. Therefore, PSG (phosphosilicate glass) must be removed, generally by wet etching: specifically, a mixture of HNO3 and HF is used to etch the lower surface and edge of the silicon wafer after the diffusion process, removing the N-type silicon at the edge and insulating the upper and lower surfaces of the silicon wafer from each other.

[0005] Similarly, B diffusion will produce BSG (borosilicate glass), which also needs to be removed. In TOPCON cells, the PSG and BSG removal processes need to be carried out in sequence.

[0006] In the prior art, a chemical treatment tank is used to contain chemical liquids for chemical treatment of the products to be processed. Typically, the liquid in the chemical treatment tank is circulated with the outside through a pump system, and the concentration of the liquid is adjusted by adding liquid to the tank through a liquid replenishing mechanism. However, when used for processes such as PSG and BSG removal on silicon wafers obtained after a diffusion process, the increase of residues in the chemical treatment tank during the transportation of the silicon wafers through the chemical treatment tank will affect the PSG / BSG removal effect of the silicon wafers.

[0007] In view of this, there is an urgent need to provide a new chemical treatment tank and photovoltaic wet processing equipment to implement the above process. Utility Model Content

[0008] The first object of the present utility model is to provide a new chemical treatment tank.

[0009] To achieve the above object, the technical solution adopted by the present utility model is: a chemical treatment tank, the chemical treatment tank comprising:

[0010] An outer tank body, which has an outer tank cavity;

[0011] An inner tank body, which has an inner tank cavity, and the inner tank body is disposed in the outer tank cavity,

[0012] wherein, the inner tank body has an inner tank bottom wall located at the bottom of the inner tank cavity, and the inner tank bottom wall extends gradually downward along a first direction.

[0013] In some embodiments, the included angle between the inner tank bottom wall and the horizontal plane is θ, wherein, 0.1° ≤ θ ≤ 10°, preferably, 0.2° ≤ θ ≤ 2°.

[0014] In some embodiments, the inner tank body has a first side wall and a second side wall, the first side wall and the second side wall are spaced apart along the first direction, a first overflow portion is provided on the first side wall, a second overflow portion is provided on the second side wall, and both the first overflow portion and the second overflow portion are configured to allow the liquid in the inner tank cavity to overflow into the outer tank cavity; wherein, the first overflow portion is higher than the second overflow portion in the vertical direction.

[0015] In some embodiments, the height difference between the first overflow portion and the second overflow portion in the vertical direction is h, wherein, 0.5 mm ≤ h ≤ 10 mm, preferably, 1 mm ≤ h ≤ 5 mm.

[0016] In some embodiments, a first channel is provided on the first side wall, a second channel is provided on the second side wall, both the first channel and the second channel communicate the inner tank cavity and the outer tank cavity, wherein, the bottom wall of the first channel is higher than the bottom wall of the second channel in the vertical direction, the bottom wall of the first channel constitutes the first overflow portion, and the bottom wall of the second channel constitutes the second overflow portion;

[0017] Or, the top end of the first side wall is higher than the top end of the second side wall in the vertical direction, the top end of the first side wall constitutes the first overflow portion, and the top end of the second side wall constitutes the second overflow portion.

[0018] In some embodiments, the outer tank body has an outer tank bottom wall located at the bottom of the outer tank cavity, and the bottom of the inner tank body is spaced from the outer tank bottom wall in the up-and-down direction.

[0019] In some embodiments, a support member is disposed between the bottom of the inner tank body and the bottom wall of the outer tank, and there is one or a plurality of support members distributed at intervals.

[0020] The second object of the present utility model is to provide a new photovoltaic wet processing device.

[0021] To achieve the above object, the technical solution adopted by the present utility model is:

[0022] A photovoltaic wet processing device, the processing device comprising:

[0023] A chemical treatment tank, the chemical treatment tank being as described above;

[0024] A transmission mechanism for transmitting a workpiece to be processed, the transmission mechanism transmitting along a second direction past the outer tank body and the inner tank body;

[0025] Wherein, the first direction is opposite to the second direction.

[0026] In some embodiments, the inner tank body has a first side wall and a second side wall, the first side wall and the second side wall are spaced apart along the first direction, and the processing device further comprises:

[0027] A liquid replenishing mechanism for replenishing liquid into the inner tank cavity, the liquid replenishing mechanism having a liquid replenishing outlet communicating with the inner tank cavity, and the liquid replenishing outlet is disposed adjacent to the first side wall; and / or,

[0028] A pumping mechanism for pumping the liquid in the outer tank cavity into the inner tank cavity, the pumping mechanism having a liquid supply outlet communicating with the inner tank cavity, and the liquid supply outlet is disposed adjacent to the first side wall.

[0029] In some embodiments, the transmission mechanism includes a plurality of transmission rollers spaced along the second direction, and the plurality of transmission rollers include: a plurality of first transmission rollers spaced in the inner tank cavity, and a plurality of second transmission rollers spaced outside the inner tank cavity. There is a first distance between two adjacent first transmission rollers, a second distance between two adjacent second transmission rollers, and a third distance between the first transmission roller and the second transmission roller adjacent along the second direction. Wherein, the second distance is greater than the first distance and the third distance.

[0030] In some embodiments, the first distance, the second distance and the third distance are all constant values, and the first distance is equal to the third distance.

[0031] In some embodiments, the processing device further includes a rinsing tank, a water washing tank, and a drying tank. The workpiece to be processed is sequentially transported along the second direction through the chemical processing tank, the rinsing tank, the water washing tank, and the drying tank. Among them, nozzles for spraying liquid onto the surface of the workpiece to be processed are provided in the rinsing tank and / or the water washing tank. The processing device further includes a liquid circulation mechanism for transferring the liquid in the rinsing tank to the chemical processing tank.

[0032] In some embodiments, the processing device further includes a gas cutting tank, and an air knife for jetting gas onto the surface of the workpiece to be processed is provided in the gas cutting tank. Among them, the gas cutting tank is arranged between the water washing tank and the drying tank.

[0033] Due to the application of the above technical solutions, the present utility model has the following advantages compared with the prior art:

[0034] The chemical processing tank provided by the embodiment of the present utility model includes an outer tank body and an inner tank body, and the inner bottom wall of the inner tank body extends downward obliquely along the first direction. During the chemical processing process of the workpiece to be processed, the inner tank body is filled with the chemical solution and overflows into the outer tank body, and new chemical solution is replenished into the inner tank body at the upstream in the first direction, so that the chemical solution can flow along the first direction in the inner tank cavity. At the same time, the workpiece to be processed is transported along the second direction opposite to the first direction through the chemical processing tank, so that the workpiece to be processed can contact the old chemical solution first and then the new chemical solution, which can not only improve the processing effect on the surface of the workpiece to be processed, but also reduce the probability that the residues generated by the reaction are brought into the subsequent tank body.

[0035] The photovoltaic wet processing device includes all the technical solutions of the above chemical processing tank, and therefore also has all the technical advantages of the battery sheet drying device. Description of the Drawings

[0036] Attached Figure 1 is a schematic structural diagram of the cooperation between the chemical processing tank and the transmission mechanism in the photovoltaic wet processing device according to an embodiment of the present utility model;

[0037] Attached Figure 2 is for attached Figure 1 is a schematic structural diagram of the inner tank body in

[0038] Attached Figure 3 is a schematic structural diagram of the cooperation between the chemical processing tank and the transmission mechanism in the photovoltaic wet processing device according to another embodiment of the present utility model;

[0039] Attached Figure 4 is for attached Figure 3 is a schematic structural diagram of the inner tank body in

[0040] Attached Figure 5 is a schematic distribution diagram of the processing tanks in the photovoltaic wet processing device according to an embodiment of the present utility model;

[0041] Attached Figure 6 is a schematic distribution diagram of treatment tanks in a photovoltaic wet processing device according to another embodiment of the present utility model;

[0042] Attached Figure 7 is a schematic diagram of the working principle of nozzles provided in a rinsing tank and / or a water washing tank in some embodiments;

[0043] Attached Figure 8 is a schematic diagram of the working principle of an air knife provided in an air cutting tank in some embodiments;

[0044] Attached Figure 9 is a schematic distribution diagram of each transfer roller and a chemical treatment tank in a transfer mechanism in some embodiments;

[0045] Attached Figure 10 is a schematic distribution diagram of each transfer roller and a chemical treatment tank in a transfer mechanism in some other embodiments;

[0046] Wherein: 1. Chemical treatment tank; 11. Outer tank body; 111. Third side wall; 112. Fourth side wall; 113. Outer tank bottom wall; 12. Inner tank body; 121. First side wall; 122. Second side wall; 123. Inner tank bottom wall; 124. First channel; 125. Second channel; 126. Top end of the first side wall; 127. Top end of the second side wall; 13. Support member;

[0047] 2. Transfer mechanism; 21. Transfer roller; 211. First transfer roller; 212. Second transfer roller; 3. Workpiece to be processed;

[0048] 4. Rinsing tank; 5. Water washing tank; 6. Drying tank; 7. Air cutting tank; 8. Nozzle; 9. Air knife.

[0049] A. First direction; B. Second direction. Detailed implementation manners

[0050] The technical solutions of the present utility model will be elaborated in detail below in conjunction with the accompanying drawings and specific embodiments, so that the advantages and features of the present utility model are more easily understood by those skilled in the art. Obviously, the described embodiments of the present application are only a part of the embodiments of the present application, rather than all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the present application.

[0051] Refer to a photovoltaic wet processing device shown in the attached drawings. The processing device includes a chemical treatment tank 1 and a transmission mechanism 2. The chemical treatment tank 1 has a treatment tank cavity for containing chemical liquid medicine; the transmission mechanism 2 is used to transmit the workpiece to be processed 3. The transmission mechanism 2 transmits along the transmission direction through the treatment tank cavity, so that the workpiece to be processed 3 contacts the chemical liquid medicine in the treatment tank cavity for chemical treatment.

[0052] The chemical treatment tank 1 includes an outer tank body 11 and an inner tank body 12. The outer tank body 11 has an outer tank cavity, and the inner tank body 12 has an inner tank cavity. The inner tank cavity is used to contain chemical liquid medicine, which is also the treatment tank cavity of the chemical treatment tank 1. The inner tank body 12 is arranged in the outer tank cavity, and the inner tank body 12 can be arranged to overflow to the outer tank body 11, so that the liquid medicine overflowing from the inner tank cavity can enter the outer tank cavity, which is beneficial to the recycling of the liquid medicine and promotes the flow of the liquid medicine in the inner tank body 12 to improve the uniformity of the liquid medicine inside it.

[0053] The inner tank body 12 has an inner tank bottom wall 123 located at the bottom of the inner tank cavity. The inner tank bottom wall 123 gradually extends downward along the first direction A. Specifically, the angle between the inner tank bottom wall 123 and the horizontal plane is θ, where 0.1° ≤ θ ≤ 10°. In some embodiments, the angle value is preferably 0.2° ≤ θ ≤ 2°.

[0054] In this photovoltaic wet processing device, the workpiece to be processed 3 is transmitted along the second direction B through the outer tank body 11 and the inner tank body 12. The second direction B is also the transmission direction of the transmission mechanism 2, and the second direction B is opposite to the first direction A. That is to say, the inner tank bottom wall 123 slopes downward in the opposite direction of the movement of the workpiece to be processed 3. Specifically in Figures 1 to 4 it, the inner tank bottom wall 123 gradually slopes downward from left to right, showing a state of being higher on the left and lower on the right; the workpiece to be processed 3 is transmitted by the transmission mechanism 2 and passes through the chemical treatment tank 1 from right to left.

[0055] During processing, at the upstream in the first direction A, that is Figures 1 to 4 in the left end of the inner tank body 12 in it, new liquid medicine is added into the inner tank cavity or the liquid medicine that overflows to the outer tank body 11 and flows back into the inner tank body 12, so that the liquid medicine in the inner tank body 12 can flow along the first direction A, which is opposite to the moving direction of the workpiece to be processed 3 (i.e., the second direction B). After the workpiece to be processed 3 enters the inner tank body 12, it first reacts with the old liquid medicine, and there are more residues in the old liquid medicine; as the workpiece to be processed 3 moves to the left, the liquid medicine at the left end is relatively fresher, the residues in the new liquid medicine decrease, the treatment effect on the surface of the workpiece to be processed 3 is improved, and at the same time, the probability of the residues being brought into the subsequent tank body is reduced.

[0056] The inner tank body 12 has a first side wall 121 and a second side wall 122, which are spaced apart along a first direction A. A first overflow portion is provided on the first side wall 121, and a second overflow portion is provided on the second side wall 122. Both the first overflow portion and the second overflow portion are configured to allow the liquid in the inner tank cavity to overflow into the outer tank cavity. Among them, the first overflow portion is higher than the second overflow portion in the vertical direction, which further facilitates the flow of the liquid medicine in the inner tank cavity along the first direction A. Specifically, the height difference between the first overflow portion and the second overflow portion in the vertical direction is h, where 0.5 mm ≤ h ≤ 10 mm. In some embodiments, the height difference can be set to 1 mm ≤ h ≤ 5 mm.

[0057] In some embodiments, referring to Figure 1 、 Figure 2 As shown, a first channel 124 is provided on the first side wall 121, and a second channel 125 is provided on the second side wall 122. Both the first channel 124 and the second channel 125 communicate the inner tank cavity with the outer tank cavity. Among them, the bottom wall of the first channel 124 is higher than the bottom wall of the second channel 125 in the vertical direction, and the height difference between them in the vertical direction is h. The bottom wall of the above-mentioned first channel 124 constitutes the first overflow portion, and the bottom wall of the second channel 125 constitutes the second overflow portion. Further, the first channel 124 and the second channel 125 are used for the workpiece 3 to be transported through the inner tank body 12 along the transport direction, so that the lower surface of the workpiece 3 contacts the liquid medicine while the upper surface does not contact the liquid medicine.

[0058] In other some embodiments, referring to Figure 3 、 Figure 4 As shown, the top end 126 of the first side wall is higher than the top end 127 of the second side wall in the vertical direction, and the height difference between them in the vertical direction is h. The top end 126 of the first side wall constitutes the first overflow portion, and the top end 127 of the second side wall constitutes the second overflow portion. Further, the workpiece 3 is transported above the first side wall 121 and above the second side wall 122 through the inner tank body 12, so that the lower surface of the workpiece 3 contacts the liquid medicine while the upper surface does not contact the liquid medicine.

[0059] In this chemical treatment tank 1, the inner tank body 12 is entirely located in the outer tank cavity of the outer tank body 11. The outer tank body 11 has an outer tank bottom wall 113 at the bottom of the outer tank cavity, and a third side wall 111 and a fourth side wall 112 that are spaced apart along the first direction A. There is a distance between the third side wall 111 and the first side wall 121, and a distance between the fourth side wall 112 and the second side wall 122. There is a distance between the outer tank bottom wall 113 and the bottom of the inner tank body 12 in the vertical direction, and a support member 13 is provided between them. The support member 13 has one or a plurality of spaced-apart ones.

[0060] There is no illustration. The processing device further includes a liquid replenishing mechanism for replenishing liquid into the inner tank cavity, specifically, a liquid medicine used to react with the surface substance of the workpiece 3 to be processed. The liquid replenishing mechanism has a liquid replenishing outlet communicating with the inner tank cavity, and the liquid replenishing outlet is disposed adjacent to the first sidewall 121, that is, the liquid medicine is replenished into the inner tank cavity upstream in the first direction A. The processing device further includes a pumping mechanism for pumping the liquid in the outer tank cavity into the inner tank cavity. The pumping mechanism has a liquid supply outlet communicating with the inner tank cavity, and the liquid supply outlet is disposed adjacent to the first sidewall 121. That is, the liquid medicine overflowing from the inner tank cavity to the outer tank cavity flows back to the inner tank cavity through the above-mentioned pumping mechanism upstream in the first direction A.

[0061] See Figure 5 As shown, in some embodiments, the processing device further includes a rinsing tank 4, a water washing tank 5, and a drying tank 6. The workpiece 3 to be processed is transported along the second direction B and sequentially passes through the chemical treatment tank 1, the rinsing tank 4, the water washing tank 5, and the drying tank 6 to sequentially rinse and remove the residual liquid medicine on the surface of the workpiece 3 to be processed, further wash with water to fully remove the liquid medicine on the surface of the workpiece 3 to be processed, and undergo a drying process. Nozzles 8 can be provided in any one of the rinsing tank 4 and the water washing tank 5 for spraying liquid onto the surface of the workpiece 3 to accelerate the flow of the liquid on the surface of the workpiece 3 and improve the cleaning effect. Further, the processing device further includes a liquid circulation mechanism (not shown in the figure) for transferring the liquid in the rinsing tank 4 to the chemical treatment tank 1 so that the liquid medicine can be recycled.

[0062] See Figure 6 As shown, in some other embodiments, the processing device further includes a gas cutting tank 7 provided between the water washing tank 5 and the drying tank 6. An air knife 9 for spraying gas onto the surface of the workpiece 3 is provided in the gas cutting tank 7. By spraying gas onto the surface of the workpiece 3, part of the liquid on the workpiece 3 can be blown off in advance, which can reduce the amount of liquid brought into the drying tank 6 after the workpiece 3 is washed with water, improve the drying effect, and reduce energy consumption.

[0063] See Figure 9 and Figure 10 As shown, in the processing device, the transmission mechanism 2 includes a plurality of transmission rollers 21 spaced along the second direction B. The plurality of transmission rollers 21 includes a plurality of first transmission rollers 211 spaced in the inner tank cavity and a plurality of second transmission rollers 212 spaced outside the inner tank cavity. Among them, there is a first distance D1 between two adjacent first transmission rollers 211, a second distance D2 between two adjacent second transmission rollers 212, and a third distance D3 between the first transmission roller 211 and the second transmission roller 212 adjacent along the second direction. The above-mentioned second distance D2 is greater than the sum of the first distance D1 and the third distance D3.

[0064] In this way, during the process that the transmission mechanism 2 carries the workpiece 3 to be processed when it is about to enter the inner tank body 12, during the process that the transmission mechanism 2 carries the workpiece 3 to be processed for transmission within the inner tank body 12, and during the process that the transmission mechanism 2 carries the workpiece 3 to flow out of the inner tank body 12, the distance between the transmission rollers 21 in the transmission mechanism 2 is relatively small, which can avoid or reduce the amplitude of jitter caused by the transmission rollers 21, so that a more stable transmission can be maintained. While in other areas, the distance between the transmission rollers 21 of the transmission mechanism 2 is relatively large, which can take into account the cost of the transmission mechanism 2 and avoid the increase in cost and the complication of the structure caused by excessive setting of the transmission rollers 21.

[0065] In this way, in some production processes, if only the lower surface of the workpiece 3 to be processed needs to be chemically treated, then before the workpiece 3 to be processed enters the chemical treatment tank 1, a water film will be formed on the upper surface of the workpiece 3 to protect the upper surface of the workpiece 3 from reacting with the chemical liquid medicine. And by making the above-mentioned improvement settings for the transmission mechanism 2, when the transmission mechanism 2 enters the chemical treatment tank 1 or is located in the chemical treatment tank 1, the transmission rollers 21 of the transmission mechanism 2 can maintain stable transmission, avoiding or reducing the local breakage or falling off of the water film laid on the upper surface of the workpiece 3 caused by the jitter of the transmission rollers 21, and further avoiding problems such as the upper surface of the workpiece 3 being contaminated and reacting with the chemical liquid medicine or the water film falling into the inner tank body 12 resulting in a decrease in the concentration of the liquid medicine.

[0066] For the convenience of production and manufacturing, the above-mentioned first distance D1, second distance D2, and third distance D3 are all constant values, and the first distance D1 is equal to the third distance D3. Specifically in this processing equipment, for this chemical treatment tank 1, as Figure 10 shown, at least one second transmission roller 212 is respectively provided between the third side wall 111 of the outer tank body 11 and the inner tank body 12, and between the fourth side wall 112 of the outer tank body 11 and the inner tank body 12. All the transmission rollers 21 located in the inner tank cavity and the outer tank cavity are arranged at equal intervals in the second direction, which is more convenient for arranging the transmission mechanism 2 during the production process.

[0067] Using the above chemical treatment tank and photovoltaic wet treatment equipment, when performing PSG removal and BSG removal treatments on the surface of the workpiece 3 to be treated, the liquid medicine in the inner tank body 12 keeps overflowing into the outer tank body 11, and new liquid medicine is replenished into the inner tank body 12 upstream in the first direction A, so that the liquid medicine can keep flowing along the first direction A in the inner tank cavity. At the same time, the workpiece 3 to be treated is transported through the chemical treatment tank 1 along the second direction B opposite to the first direction A. This enables the workpiece 3 to contact the old liquid medicine first and then the new liquid medicine, which can not only improve the treatment effect on the surface of the workpiece 3, but also reduce the probability that the residues generated by the reaction are brought into the subsequent tank body. At the same time, the transmission mechanism 2 can maintain stable transmission when the workpiece 3 enters or exits the inner tank body 12 and during the transmission process in the inner tank body 12, avoiding the breakage or dropping of the water film on the upper surface of the workpiece 3 due to jitter during the transmission process, avoiding damage to the upper surface of the workpiece 3, and avoiding the reduction of the liquid medicine concentration in the inner tank body 12 from affecting the treatment effect.

[0068] Certainly, the chemical treatment tank 1 and the photovoltaic wet treatment equipment provided in the above embodiments are not only applicable to the PSG removal and BSG removal processes of silicon wafers, but can also be used in other surface treatment processes of silicon wafers, such as processes that require contacting chemical liquid medicine for reaction, such as film removal, development, and electroplating. Certainly, the workpiece 3 to be treated is not limited to silicon wafers, and can also be other products that require surface treatment.

[0069] The above embodiments are only used to illustrate the technical concept and features of the present invention. The purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the protection scope of the present invention.

Claims

1. A chemical treatment tank, characterized in that, The chemical treatment tank includes: An outer tank body having an outer tank cavity; An inner tank body having an inner tank cavity, and the inner tank body is disposed in the outer tank cavity. Wherein, the inner tank body has an inner tank bottom wall located at the bottom of the inner tank cavity, and the inner tank bottom wall gradually extends downwardly and obliquely along a first direction.

2. The chemical treatment tank according to claim 1, wherein: The included angle between the inner tank bottom wall and the horizontal plane is θ, wherein 0.1° ≤ θ ≤ 10°.

3. The chemical treatment tank according to claim 1, wherein: The inner tank body has a first side wall and a second side wall, the first side wall and the second side wall are spaced apart along the first direction, a first overflow portion is provided on the first side wall, and a second overflow portion is provided on the second side wall. Both the first overflow portion and the second overflow portion are configured to allow the liquid in the inner tank cavity to overflow into the outer tank cavity. Wherein, the first overflow portion is higher than the second overflow portion in the vertical direction.

4. The chemical treatment tank according to claim 3, wherein: The height difference between the first overflow portion and the second overflow portion in the vertical direction is h, wherein 0.5 mm ≤ h ≤ 10 mm.

5. The chemical treatment tank according to claim 3, wherein: A first channel is provided on the first side wall, and a second channel is provided on the second side wall. Both the first channel and the second channel communicate the inner tank cavity and the outer tank cavity. Wherein, the bottom wall of the first channel is higher than the bottom wall of the second channel in the vertical direction, the bottom wall of the first channel constitutes the first overflow portion, and the bottom wall of the second channel constitutes the second overflow portion; Or, the top end of the first side wall is higher than the top end of the second side wall in the vertical direction, the top end of the first side wall constitutes the first overflow portion, and the top end of the second side wall constitutes the second overflow portion.

6. The chemical treatment tank according to claim 1, wherein: The outer tank body has an outer tank bottom wall located at the bottom of the outer tank cavity, and the bottom of the inner tank body is spaced from the outer tank bottom wall in the up-and-down direction; A support member is disposed between the bottom of the inner tank body and the outer tank bottom wall, and the support member has one or a plurality of spaced-apart ones.

7. A photovoltaic wet processing device, characterized in that, The processing device includes: A chemical treatment tank as described in any one of claims 1 to 6; A transmission mechanism for transmitting the workpiece to be processed, and the transmission mechanism transmits along a second direction past the outer tank body and the inner tank body; Wherein, the first direction is opposite to the second direction.

8. The photovoltaic wet processing equipment according to claim 7, characterized in that: The inner tank body has a first side wall and a second side wall, the first side wall and the second side wall are spaced apart along the first direction, and the processing device further includes: A liquid replenishing mechanism for replenishing liquid into the inner tank cavity, the liquid replenishing mechanism has a liquid replenishing outlet communicating with the inner tank cavity, and the liquid replenishing outlet is disposed adjacent to the first side wall; and / or, A pumping mechanism for pumping the liquid in the outer tank cavity into the inner tank cavity, the pumping mechanism has a liquid supply outlet communicating with the inner tank cavity, and the liquid supply outlet is disposed adjacent to the first side wall.

9. The photovoltaic wet processing equipment according to claim 7, characterized in that: The transmission mechanism includes a plurality of transmission rollers arranged at intervals along the second direction. The plurality of transmission rollers include: a plurality of first transmission rollers spaced in the cavity of the inner groove, and a plurality of second transmission rollers spaced outside the cavity of the inner groove. There is a first spacing between two adjacent first transmission rollers, a second spacing between two adjacent second transmission rollers, and a third spacing between the first transmission roller and the second transmission roller arranged adjacent to each other along the second direction. Wherein, the second spacing is greater than the first spacing and the third spacing.

10. The photovoltaic wet processing equipment according to claim 7, characterized in that: The processing device further includes a rinsing tank, a water washing tank and a drying tank. The workpiece to be processed is transmitted along the second direction and sequentially passes through the chemical processing tank, the rinsing tank, the water washing tank and the drying tank. Wherein, nozzles for spraying liquid onto the surface of the workpiece to be processed are arranged in the rinsing tank and / or the water washing tank. The processing device further includes a liquid circulation mechanism for transferring the liquid in the rinsing tank to the chemical processing tank; The processing device further includes a gas cutting tank, and an air knife for jetting gas onto the surface of the workpiece to be processed is arranged in the gas cutting tank. Wherein, the gas cutting tank is arranged between the water washing tank and the drying tank.

Images