Slit coating device

Abstract

The utility model provides a slit coating device which comprises a first module, a second module and a gasket structure, the first module is provided with a liquid storage tank and a liquid inlet communicated with the liquid storage tank; the second module and the first module are oppositely arranged and connected, a pump-back channel is formed in the second module, and a groove opening of the liquid storage groove faces one side of the second module; the gasket structure is clamped between the first module and the second module, so that a liquid outlet slit is formed among the first module, the second module and the gasket structure; the two ends of the pumpback channel penetrate through the two side faces of the second module correspondingly, so that the two ends of the pumpback channel communicate with the liquid outlet slit and an external liquid pumping device correspondingly. According to the utility model, the problem in the prior art that the thickness of the perovskite film is seriously non-uniform due to liquid bead bridges remained at the starting end and the ending end of coating is solved.

Description

Technical Field

[0001] This utility model relates to the technical field of slot coating equipment, and more specifically, to a slot coating device. Background Technology

[0002] Currently, perovskite thin films, as an emerging semiconductor material, have broad application prospects in solar cells, X-ray detection, and displays. To achieve efficient, controllable, and uniform large-area perovskite thin film fabrication, the slit coating method is widely used.

[0003] However, in existing technologies, perovskite solutions are easily wasted at the beginning and end of coating, leading to increased material costs and unsatisfactory coating results. Furthermore, due to the low viscosity and good wettability of perovskite solutions, residual liquid droplets at the beginning and end of coating can cause severe unevenness in the thickness of the perovskite film. If a syringe pump is used to directly back-pump the solution at the end, a large number of air bubbles will be generated in the reservoir, severely affecting the next coating process.

[0004] Therefore, there is an urgent need for a slit coating device that can independently retract the perovskite solution at the beginning and end of the coating process to solve the above problems. Utility Model Content

[0005] The main objective of this invention is to provide a slit coating device to solve the problem in the prior art where residual liquid droplet bridges at the beginning and end of the coating process cause severe unevenness in the thickness of the perovskite film.

[0006] To achieve the above objectives, this utility model provides a slit coating device, comprising a first module, a second module, and a gasket structure. The first module has a liquid storage tank and a liquid inlet communicating with the liquid storage tank. The second module is disposed opposite to and connected to the first module, and a backflow channel is provided on the second module. The opening of the liquid storage tank faces the second module. The gasket structure is sandwiched between the first module and the second module to form a liquid outlet slit between the three. The two ends of the backflow channel respectively penetrate the two sides of the second module so that the two ends of the backflow channel are respectively connected to the liquid outlet slit and an external liquid extraction device.

[0007] Furthermore, the first end of the retraction channel penetrates the surface of the second module facing the first module, so that the first end of the retraction channel is connected to the liquid outlet slit, and the second end of the retraction channel is inclined upward in a direction away from the liquid outlet slit, and penetrates the surface of the second module facing away from the first module.

[0008] Furthermore, the angle A between the extension direction of the retraction channel and the horizontal direction satisfies: 0°≤A≤90°.

[0009] Furthermore, the second module includes a connected module body and a guide tip. A retraction channel is formed on the module body, with the first end of the retraction channel located close to the guide tip and at the geometric center of the module body along its length. The second end of the retraction channel is located at the geometric center of the module body along its length.

[0010] Furthermore, the pullback channel extends along a straight line, or the pullback channel extends along a curve.

[0011] Furthermore, the cross-section of the retraction channel is one of the following: circular, elliptical, or polygonal.

[0012] Furthermore, the gasket structure includes a support plate and two guide plates, which are respectively connected to both ends of the support plate along its length and form a C-shaped structure; at least one of the guide plates has a grid-like end away from the support plate to provide capillary wetting of the formulation solution at the outlet slit; or, at least one of the guide plates has a mesh-like end away from the support plate to provide capillary wetting of the formulation solution at the outlet slit.

[0013] Furthermore, the end of the guide plate away from the support plate has multiple grid strips, which are evenly distributed.

[0014] Furthermore, the opening of the liquid storage tank is strip-shaped and extends along the length of the first module. The opening of the liquid storage tank is higher than the opening of the return channel at the end facing the first module.

[0015] Furthermore, the first module has a first mounting hole, the gasket structure has a second mounting hole at the position opposite to the first mounting hole, the second module has a third mounting hole at the position opposite to the second mounting hole, and the slit coating device also includes a fastener, which passes through the third mounting hole and the second mounting hole in sequence and extends into the first mounting hole to connect the first module, the gasket structure, and the second module.

[0016] The present invention provides a slit coating device, comprising a first module, a second module, and a gasket structure. The first module has a liquid storage tank and a liquid inlet communicating with the liquid storage tank. The second module is disposed opposite to and connected to the first module, and a backflow channel is provided on the second module. The opening of the liquid storage tank faces the second module. The gasket structure is sandwiched between the first module and the second module to form a liquid outlet slit between the three. The two ends of the backflow channel respectively penetrate the two sides of the second module so that the two ends of the backflow channel are respectively connected to the liquid outlet slit and an external liquid extraction device.

[0017] By opening a back-pull channel on the second module, with both ends of the back-pull channel penetrating the two sides of the second module respectively, the two ends of the back-pull channel are connected to the liquid outlet slit and the external liquid extraction device respectively. This ensures that the external liquid extraction device can control the size of the residual liquid droplet bridges at the beginning and end of the coating through the connection between the external liquid extraction device and the back-pull channel. After being drawn by the external liquid extraction device, the excess formulation solution participating in the liquid droplet bridge is removed, thereby ensuring the uniformity of the wet film thickness at the beginning and end of the coating. Attached Figure Description

[0018] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0019] Figure 1 This diagram illustrates the state structure of liquid droplet bridges during the coating process according to an optional embodiment of the present invention.

[0020] Figure 2 An exploded structural schematic diagram of a slot coating apparatus according to an alternative embodiment of the present invention is shown.

[0021] Figure 3 It shows Figure 2 A schematic diagram of the gasket structure in the slit coating device;

[0022] Figure 4 It shows Figure 2 A schematic diagram of the structure of the second module of the slot coating device facing the first module;

[0023] Figure 5 It shows Figure 4 A cross-sectional view of the second module.

[0024] The above figures include the following reference numerals:

[0025] 10. First module; 11. Liquid storage tank; 12. Liquid inlet; 13. First assembly hole;

[0026] 20. Second module; 21. Module body; 211. Retraction channel; 22. Guide tip; 23. Third assembly hole;

[0027] 30. Gasket structure; 31. Support plate; 32. Guide plate; 321. Grid strip; 33. Second assembly hole. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present utility model or its application or use. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model without creative effort are within the scope of protection of the present utility model.

[0029] To address the problem in existing technologies where residual liquid droplets at the beginning and end of coating cause severe unevenness in the thickness of perovskite films, this invention provides a slit coating device.

[0030] like Figures 1 to 5 As shown, the slit coating device includes a first module 10, a second module 20, and a gasket structure 30. The first module 10 has a liquid storage tank 11 and a liquid inlet 12 communicating with the liquid storage tank 11. The second module 20 is arranged opposite to and connected to the first module 10, and a return channel 211 is opened on the second module 20. The opening of the liquid storage tank 11 is arranged facing the second module 20. The gasket structure 30 is sandwiched between the first module 10 and the second module 20 to form a liquid outlet slit between the three. The two ends of the return channel 211 respectively penetrate through the two sides of the second module 20 so that the two ends of the return channel 211 are respectively connected to the liquid outlet slit and an external liquid extraction device.

[0031] The present invention provides a slit coating device, comprising a first module 10, a second module 20, and a gasket structure 30. The first module 10 has a liquid storage tank 11 and a liquid inlet 12 communicating with the liquid storage tank 11. The second module 20 is disposed opposite to and connected to the first module 10, and a return channel 211 is provided on the second module 20. The opening of the liquid storage tank 11 is disposed facing the second module 20. The gasket structure 30 is sandwiched between the first module 10 and the second module 20 to form a liquid outlet slit between the three. The two ends of the return channel 211 respectively penetrate the two sides of the second module 20 so that the two ends of the return channel 211 are respectively connected to the liquid outlet slit and an external liquid extraction device.

[0032] By opening a return channel 211 on the second module 20, and having both ends of the return channel 211 penetrating the two sides of the second module 20 respectively, the two ends of the return channel 211 are connected to the liquid outlet slit and the external liquid extraction device respectively. This ensures that the external liquid extraction device can control the size of the residual liquid droplet bridge at the beginning and end of the coating through the connection between the external liquid extraction device and the return channel 211. After being drawn by the external liquid extraction device, the excess formulation solution participating in the liquid droplet bridge is drawn away, thereby ensuring the uniformity of the wet film thickness at the beginning and end of the coating.

[0033] Specifically, refer to Figure 1 It is known that a liquid droplet bridge is formed between the lip of the liquid outlet slit in the slit coating device and the substrate. Wet film coating is completed by the movement of the substrate relative to the liquid droplet bridge. At the beginning and end of the coating process, the residual formulation solution on the liquid droplet bridge results in highly uneven wet film thickness. (Refer to...) Figure 1 As the substrate moves, it can be seen that after the excess formulation solution in the liquid droplet bridge is drawn back through the back-draw channel 211 of this application, the overall volume of the liquid droplet bridge is reduced, which helps to ensure the uniformity of the wet film thickness at the beginning and end of the coating.

[0034] like Figure 2 As shown, the first module 10 has a first assembly hole 13, the gasket structure 30 has a second assembly hole 33 opposite to the first assembly hole 13, and the second module 20 has a third assembly hole 23 opposite to the second assembly hole 33. The slit coating device also includes fasteners that pass through the third assembly hole 23, the second assembly hole 33, and extend into the first assembly hole 13 in sequence to connect the first module 10, the gasket structure 30, and the second module 20. This ensures a tight and reliable connection between the first module 10, the second module 20, and the gasket structure 30, thereby ensuring the reliability of the liquid outlet slit formed between them. The perovskite precursor liquid is extruded through the liquid outlet slit to complete the wet film coating.

[0035] It should be noted that, in this application, the formulation solution at the outlet slit is a perovskite precursor solution.

[0036] Specifically, fasteners are sequentially passed through the third assembly hole 23, the second assembly hole 33 and extended into the first assembly hole 13, thereby tightly connecting the first module 10, the second module 20 and the gasket structure 30. The perovskite precursor liquid flows continuously into the storage tank 11 through the inlet 12, is mixed evenly in the storage tank 11 and then extruded through the outlet slit. The perovskite wet film is prepared in conjunction with the back-and-forth movement of the substrate. Furthermore, the return channel 211 of the second module 20 remains closed during the movement of the substrate.

[0037] It should be noted that in this application, the perovskite components need to be mixed in a certain stoichiometric ratio and then dissolved in an organic solvent to obtain a perovskite precursor solution, and a perovskite wet film is prepared by a one-step coating method.

[0038] Furthermore, at the beginning of the coating process, the distance between the bottom liquid outlet slit of the slit coating device and the substrate is 200 μm, and the perovskite precursor solution is pumped in at a uniform speed until the liquid droplet bridge on the bottom side can fill the entire left and right sides of the slit. At this time, due to the low viscosity of the perovskite precursor solution, the liquid droplet bridge accumulates at both ends of the slit, resulting in a thicker wet film at the beginning. By slowly retracting part of the solution in the liquid droplet bridge through the retraction channel 211 of the second module 20, the amount of solution in the liquid droplet bridge can be reduced, making the thickness of the wet film at the beginning more uniform.

[0039] It should be noted that before the substrate begins to move, the grid-like or mesh-like pad structure 30 stores a portion of the perovskite precursor solution due to capillary wetting. As the substrate moves relative to the substrate, the perovskite precursor solution squeezed out from the outlet slit of the slit coating device achieves wet film coating. Because the perovskite precursor solution has low viscosity and good wettability, the width of the wet film is the width of the entire slit coating device. At this time, the perovskite precursor solution in the grid strips 321 of the pad structure 30 can play a role in adjusting the film thickness on both sides of the coating.

[0040] Furthermore, at the end of the coating process, the slit coating device moves downward to a position 100 μm away from the substrate. At this point, a large amount of perovskite precursor solution remains in the liquid droplet bridge. If the existing technology is used, directly drawing back at the liquid inlet 12 will cause a large number of bubbles in the liquid storage tank 11. However, this application can make the thickness of the wet film end more uniform by slowly drawing back the solution in the liquid droplet bridge through the drawing back channel 211 of the second module 20.

[0041] like Figure 2 , Figure 4 ,and Figure 5 As shown, the first end of the backflow channel 211 penetrates the surface of the second module 20 facing the first module 10, so that the first end of the backflow channel 211 communicates with the liquid outlet slit. The second end of the backflow channel 211 is inclined upward in a direction away from the liquid outlet slit and penetrates the surface of the second module 20 facing away from the first module 10. In this way, it is ensured that the formulation solution is slowly backflowed through the backflow channel 211, thereby ensuring that a large number of bubbles are not generated.

[0042] It should be noted that in this application, the angle A between the extension direction of the retrieval channel 211 and the horizontal direction satisfies: 0°≤A≤90°. This ensures the slow retrieval of the formulation solution.

[0043] like Figure 2 , Figure 4,and Figure 5 As shown, the second module 20 includes a connected module body 21 and a guide tip 22. A retraction channel 211 is formed on the module body 21, with its first end positioned near the guide tip 22 and located at the geometric center of the module body 21 along its length. The second end of the retraction channel 211 is also located at the geometric center of the module body 21 along its length. This ensures that the second end of the retraction channel 211 can uniformly retract excess solution from the liquid droplet bridge.

[0044] Alternatively, the pullback channel 211 extends along a straight line, or the pullback channel 211 extends along a curve.

[0045] Optionally, the cross-section of the retraction channel 211 is one of a circle, an ellipse, or a polygon.

[0046] like Figure 3 As shown, the gasket structure 30 includes a support plate 31 and two guide plates 32. The two guide plates 32 are connected to both ends of the support plate 31 along its length, forming a C-shaped structure. At least one of the guide plates 32 has a grid-like end away from the support plate 31 to provide capillary wetting of the formulation solution at the outlet slit; or, at least one of the guide plates 32 has a mesh-like end away from the support plate 31 to provide capillary wetting of the formulation solution at the outlet slit. In this way, the grid-like or mesh-like guide plates 32 can provide capillary wetting of the formulation solution, thereby ensuring the uniformity of the thickness on both sides of the wet film.

[0047] like Figure 3 As shown, the guide plate 32 has multiple grid strips 321 at the end away from the support plate 31, and the multiple grid strips 321 are evenly distributed.

[0048] Of course, in an embodiment of this application not shown, the sizes of the multiple grid strips 321 may be inconsistent or unevenly distributed, and can be designed according to specific needs.

[0049] like Figure 1 As shown, the opening of the liquid storage tank 11 is strip-shaped and extends along the length of the first module 10. The opening of the liquid storage tank 11 is higher than the opening of the return channel 211 at the end facing the first module 10. This ensures the reliability of the liquid discharge from the outlet slit.

[0050] The present invention provides a slit coating device, comprising a first module 10, a second module 20, and a gasket structure 30. The first module 10 has a liquid storage tank 11 and a liquid inlet 12 communicating with the liquid storage tank 11. The second module 20 is disposed opposite to and connected to the first module 10, and a return channel 211 is provided on the second module 20. The opening of the liquid storage tank 11 is disposed facing the second module 20. The gasket structure 30 is sandwiched between the first module 10 and the second module 20 to form a liquid outlet slit between the three. The two ends of the return channel 211 respectively penetrate the two sides of the second module 20 so that the two ends of the return channel 211 are respectively connected to the liquid outlet slit and an external liquid extraction device.

[0051] By opening a return channel 211 on the second module 20, and having both ends of the return channel 211 penetrating the two sides of the second module 20 respectively, the two ends of the return channel 211 are connected to the liquid outlet slit and the external liquid extraction device respectively. This ensures that the external liquid extraction device can control the size of the residual liquid droplet bridge at the beginning and end of the coating through the connection between the external liquid extraction device and the return channel 211. After being drawn by the external liquid extraction device, the excess formulation solution participating in the liquid droplet bridge is drawn away, thereby ensuring the uniformity of the wet film thickness at the beginning and end of the coating.

[0052] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0053] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this invention. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0054] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0055] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0056] It should be noted that the terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in sequences other than those illustrated or described herein.

[0057] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A slot coating apparatus, characterized in that, include: The first module (10) has a liquid storage tank (11) and a liquid inlet (12) communicating with the liquid storage tank (11); The second module (20) is arranged opposite to and connected to the first module (10), and the second module (20) is provided with a backflow channel (211), and the opening of the liquid storage tank (11) is arranged facing the second module (20); A gasket structure (30) is sandwiched between the first module (10) and the second module (20) to form a liquid outlet slit between the three; The two ends of the backflow channel (211) respectively penetrate the two sides of the second module (20), so that the two ends of the backflow channel (211) are respectively connected to the liquid outlet slit and the external liquid extraction device.

2. The slit coating apparatus according to claim 1, characterized in that, The first end of the backflow channel (211) penetrates the surface of the second module (20) facing the first module (10) so that the first end of the backflow channel (211) is connected to the liquid outlet slit. The second end of the backflow channel (211) is inclined upward in a direction away from the liquid outlet slit and penetrates the surface of the second module (20) facing away from the first module (10).

3. The slit coating apparatus according to claim 2, characterized in that, The angle A between the extension direction of the retraction channel (211) and the horizontal direction satisfies: 0°≤A≤90°.

4. The slit coating apparatus according to claim 2, characterized in that, The second module (20) includes a connected module body (21) and a guide tip (22). The retraction channel (211) is opened on the module body (21), and the first end of the retraction channel (211) is located close to the guide tip (22) and at the geometric center of the module body (21) in the length direction. The second end of the retraction channel (211) is located at the geometric center of the module body (21) in the length direction.

5. The slit coating apparatus according to claim 1, characterized in that, The retraction channel (211) extends along a straight line, or the retraction channel (211) extends along a curve.

6. The slit coating apparatus according to any one of claims 1 to 5, characterized in that, The cross-section of the retraction channel (211) is one of a circle, an ellipse, or a polygon.

7. The slit coating apparatus according to claim 1, characterized in that, The gasket structure (30) includes a support piece (31) and two guide pieces (32). The two guide pieces (32) are respectively connected to the two ends of the support piece (31) in the length direction and form a C-shaped structure. At least one of the two guide plates (32) has a grid-like structure at one end away from the support plate (31) to provide capillary wetting of the formulation solution at the liquid outlet slit; or, At least one of the two guide plates (32) has a mesh-like end away from the support plate (31) to provide capillary wetting of the formulation solution at the liquid outlet slit.

8. The slit coating apparatus according to claim 7, characterized in that, The guide plate (32) has a plurality of grid strips (321) at one end away from the support plate (31), and the plurality of grid strips (321) are evenly distributed.

9. The slit coating apparatus according to claim 1, characterized in that, The opening of the liquid storage tank (11) is strip-shaped and extends along the length of the first module (10). The opening of the liquid storage tank (11) is higher than the channel opening of the return channel (211) at the end facing the first module (10).

10. The slit coating apparatus according to claim 1, characterized in that, The first module (10) has a first mounting hole (13), the gasket structure (30) has a second mounting hole (33) at a position opposite to the first mounting hole (13), the second module (20) has a third mounting hole (23) at a position opposite to the second mounting hole (33), and the slit coating device also includes a fastener, which passes through the third mounting hole (23), the second mounting hole (33) in sequence and extends into the first mounting hole (13) to connect the first module (10), the gasket structure (30), and the second module (20).

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