CN218749986U - drying device - Google Patents

Abstract

The utility model relates to a drying device includes: a cavity; a table located within the cavity; a support part which penetrates the worktable; and a substrate positioned on the support, wherein the stage is heated in a drying process, and wherein the substrate is spaced apart from the stage in the drying process.

Description

Drying device

Technical Field

The present disclosure relates to a drying device.

Background

The solution-based printing method can directly perform large-area patterning without complicated processes such as vacuum and etching, which are required in the conventional method. Therefore, the solution-based printing method is widely used for forming an organic layer of a color filter or a light emitting element of a Liquid Crystal Display (Liquid Crystal Display). An ink, which is a solution in which an organic substance is dissolved, is ejected to a desired position by a solution printing method to form an organic layer. The ejected ink is dried by the solvent to form an organic layer.

The light emitting element is a self-light emitting element which is excellent in power consumption, response speed, viewing angle, and contrast. The light-emitting element includes an organic layer including a light-emitting layer that generates excitons to emit light, and an electrode. The organic layer of the light-emitting element can be formed by a solution-based printing method. However, in the case of forming an organic layer by a solution-based printing method, the organic layer is formed to have a non-uniform thickness, and the surface may be formed to be concave or convex. Such a concave or convex surface causes a reduction in reliability of the element, such as uneven luminance in a light emitting region of the pixel, shortening of the life of the element, and the like.

SUMMERY OF THE UTILITY MODEL

Embodiments are directed to providing a drying apparatus that can form a uniform layer.

The drying device according to the present embodiment includes: a cavity; a table located within the cavity; a support part which penetrates the worktable; and a substrate positioned on the support, wherein the stage is heated in a drying process, and the substrate is spaced apart from the stage in the drying process.

A substance layer may be coated on the upper portion of the substrate.

The substance layer may be applied by an ink-jet method.

The substance layer may be an organic layer.

The substance layer may be one or more layers among layers constituting the light emitting element.

The substrate may be spaced apart from the table by a distance of 2mm to 150mm.

The substrate may be spaced apart from the cavity by a distance of 2mm to 150mm.

The ratio of the separation distance between the substrate and the stage and the separation distance between the substrate and the chamber may be 1.

In the drying process, a distance between the substrate and the chamber may be greater than a distance between the substrate and the stage.

In the drying process, the substrate may be spaced apart from the table while the table is lowered.

In the drying process, the substrate and the table may be spaced apart when the support portion is raised.

In the drying process, the stage and the substrate may not be in direct contact.

The drying gas generated in the drying process may flow toward an upper region and a lower region of the substrate.

The chamber may include an exhaust port that exhausts the dry gas.

The drying device may further include: an upper plate located between an upper portion of the substrate and the cavity.

In the drying process, the upper plate may be heated.

The upper plate and the base plate may not be in direct contact.

(effects of utility model)

According to the embodiments, a drying apparatus that can form a uniform layer is provided.

Drawings

Fig. 1 is a simplified diagram showing the structure of the drying apparatus according to the present embodiment.

Fig. 2 is a schematic diagram showing a configuration in which the material layer is dried in the drying apparatus according to the present embodiment.

Fig. 3 shows a drying apparatus in which the substrate is in direct contact with the stage.

Fig. 4 shows a configuration in which the material layer is dried in the drying apparatus of fig. 3.

Fig. 5 to 7 illustrate the principle of evaporation in the case where the substrate is in direct contact with the stage.

Fig. 6 shows the flow within the substance layer during drying of the embodiment of fig. 5.

Fig. 7 shows the shape of the substance layer before and after evaporation of the embodiment of fig. 5.

Fig. 8 to 10 illustrate the principle of evaporation in the case where the substrate does not directly contact the stage.

Fig. 9 shows the flow within the substance layer during drying in the embodiment of fig. 8.

Fig. 10 shows the shape of the substance layer before and after evaporation in the embodiment of fig. 8.

Fig. 11 shows the profile of the substance layer dried while the pressure and temperature are made different.

Fig. 12 shows the profile of the substance layer after drying in a drying device in which the substrate is in direct contact with the table.

Fig. 13 is a 2D profile of the substance layer having the profile of fig. 12, and fig. 14 illustrates a light emitting element including the substance layer having the profile of fig. 12.

Fig. 15 shows the outline of the substance layer after drying in a drying device in which the substrate is not in direct contact with the stage.

Fig. 16 is a 2D profile of a material layer having the profile of fig. 15, and fig. 17 shows a light emitting element including a material layer having the profile of fig. 15.

Fig. 18 is a graph of efficiency measured in terms of color coordinates for a display device having the profile of fig. 12 and a display device having the profile of fig. 15.

Fig. 19 shows a drying apparatus according to another embodiment.

Description of the symbols:

1000: a cavity; 100: a work table; 200: a support portion; 300: a substrate; 500: an upper plate.

Detailed Description

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily implement the embodiments. The present invention can be realized in various forms, and is not limited to the embodiments described herein.

In order to clearly explain the present invention, portions that are not related to the description are omitted, and the same or similar components are given the same reference numerals throughout the specification.

In the drawings, the size and thickness of each component are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to the illustrated case. In the drawings, the thickness is exaggerated for clarity of the layers and regions. In addition, in the drawings, the thicknesses of parts of layers and regions are exaggeratedly shown for convenience of explanation.

Further, the case where a layer, a film, a region, a plate, or the like is partially located on or over other portions includes not only the case where it is directly located on other portions but also the case where other portions are present therebetween. In contrast, when a certain portion is directly located on other portions, it means that there are no other portions therebetween. The term "on or above the reference portion" means on or below the reference portion, and does not necessarily mean on or above the reference portion in the opposite direction to the gravitational force.

In addition, when a certain component is included in a certain part of the specification, unless otherwise stated, the other component is not excluded, but the other component may be included.

In the present invention, the term "on-plane" refers to a plan view of a target portion, and the term "on-plane" refers to a side view of a cross section of the target portion taken perpendicularly.

Next, a drying device according to an embodiment of the present invention will be described below with reference to the drawings.

Fig. 1 is a simplified diagram showing the structure of the drying apparatus according to the present embodiment. Referring to fig. 1, the drying apparatus according to the present embodiment includes a chamber 1000, a table 100 positioned in the chamber 1000, a support 200 provided to penetrate the table 100 and move up and down, and a substrate 300 positioned on the support 200.

The chamber 1000 may include a first chamber 1100 and a second chamber 1200 separated from each other. As the first chamber 1100 is separated from the second chamber 1200, the substrate 300 may be positioned within the chamber 1000. Although fig. 1 illustrates a configuration in which the first chamber 1100 and the second chamber 1200 are spaced apart from each other, the first chamber 1100 and the second chamber 1200 may be combined and sealed in a subsequent drying process. The exhaust port 1300 may be located at a lower portion of the chamber 1000. Vapor generated during the drying process may be discharged through the exhaust port 1300.

The table 100 may be heated during the drying process. A material layer (not shown) on the substrate 300 may be dried by the heated table 100. The substance layer may be a light-emitting substance applied on the substrate 300 by an ink-jet process or the like. The substrate 300 may be glass, but is not limited thereto.

As shown in fig. 1, in the drying apparatus according to the present embodiment, the substrate 300 is spaced apart from the stage 100. That is, the substrate 300 does not directly contact the table 100 by the support 200 protruding upward of the table 100.

Such a process may be implemented by raising the support 200 after the substrate 300 is positioned on the table 100. Alternatively, the substrate 300 may be placed on the stage 100 and then the stage 100 may be lowered.

Thereby, the substrate 300 is not in direct contact with the stage 100 but a space is created therebetween, so that the drying gas can flow to the upper and lower portions of the substrate 300 during the drying of the substance applied to the upper portion of the substrate 300. Therefore, the flowing space of the drying gas is expanded, so that the drying can be well performed.

In an embodiment, a distance D1 between the lower portion of the substrate 300 and the stage 100 may be 2mm to 150mm. The above-described effects can be obtained as long as the substrate 300 is not in direct contact with the table 100 but spaced apart. Therefore, the distance D1 between the substrate 300 and the stage 100 may be 2mm or more. When the distance D1 between the substrate 300 and the stage 100 exceeds 150mm, the distance is too long, and drying of the material layer on the substrate 300 may not be satisfactorily achieved.

Further, a distance D2 between the upper portion of the substrate 300 and the cavity 1000 may be 2mm to 150mm. In the case where the distance D2 between the substrate 300 and the chamber 1000 is below 2mm, a space in which the drying gas may flow is insufficient, so that drying may not be well achieved, and in the case where the distance D2 between the substrate 300 and the chamber 1000 is above 150mm, the inside of the chamber 1000 may not be sufficiently heated, so that drying may be delayed.

In an embodiment, the distance D1 between the substrate 300 and the stage 100 and the distance D2 between the substrate 300 and the chamber 1000 may be similar or different. As an example, the ratio of the distance D1 between the substrate 300 and the stage 100 and the distance D2 between the substrate 300 and the chamber 1000 may be 1.

In an embodiment, the distance D2 between the substrate 300 and the chamber 1000 may be greater than the distance D1 between the substrate 300 and the stage 100. This is because the substance layer to be dried is located on the upper portion of the substrate 300, and therefore, in order to achieve effective drying, it is preferable that the upper space of the substrate 300 is larger.

The optimal separation distance may be different according to the size of the substrate 300. That is, if the size of the substrate 300 is large, the evaporation amount is large, and thus the optimal separation distance can be made larger. The separation distance may be appropriately adjusted according to the size of the substrate 300.

Even if the size of the substrate 300 becomes different, it is preferable that the distance D2 between the substrate 300 and the chamber 1000 is greater than the distance D1 between the substrate 300 and the stage 100. As long as the substrate 300 is not in direct contact with the stage 100 but spaced apart, it may have a similar effect regardless of the spaced-apart distance.

A substance constituting a light-emitting element layer may be coated on the substrate 300. For example, a light-emitting layer material may be applied on the substrate 300. At this time, the light emitting layer substance may be applied by an ink jet method. The partition walls may be positioned on the substrate 300, and a light emitting layer substance may be applied to spaces between the partition walls by an ink jet method. By heating the stage 100, the substance on the substrate 300 may be dried. In this specification, a layer which is applied by an ink jet method and is provided over the substrate 300 is referred to as a substance layer. The material layer may be a material layer constituting the light emitting element, such as an electron injection layer, an electron transport layer, a light emitting layer, a hole transport layer, a hole injection layer, or the like, but is not limited thereto. The material layer may be an organic layer, but is not limited thereto.

As shown in fig. 1, in the drying apparatus according to the present embodiment, the table 100 is not in direct contact with the substrate 300, so that the coffee ring effect can be suppressed during the drying process.

The coffee ring effect represents a phenomenon in which particles are accumulated at an edge position when evaporating a liquid including fine particles. The liquid has a characteristic of evaporating from the edge position, and the liquid located on the back side moves to the edge position side which becomes empty by evaporation, and the original form is intended to be maintained to the maximum. At this time, in the case where particles are included in the liquid, the particles are pushed together with the liquid and may be accumulated at the edge position, which is a coffee ring effect.

Hereinafter, the effect of the drying device according to the present embodiment will be described.

Fig. 2 is a schematic diagram showing a configuration in which the material layer 400 is dried in the drying apparatus according to the present embodiment. Referring to fig. 2, partition walls 350 may be positioned on a substrate 300, and a substance layer 400 applied by an inkjet method may be positioned between the partition walls 350. The material layer 400 may be a light emitting layer, but is not limited thereto.

As shown in fig. 1 and 2, in the drying apparatus according to the present embodiment, since the substrate 300 is not in direct contact with the stage 100, the substance layer 400 can be uniformly evaporated over the entire substrate 300. That is, heat is not directly transferred from the stage 100 to the substrate 300, but the stage 100 heats air inside the chamber 1000, so that heat is uniformly transferred to the substrate 300 by dry air.

Unlike the present embodiment, in the case where the substrate 300 is in direct contact with the table 100, the flow may be formed in a direction from the center of the substance layer 400 toward the edge position (i.e., toward the side adjacent to the partition wall 350) by the above-described coffee ring effect. In this case, by such a flow, the substance layer 400 can be dried into a Profile (Profile) of a U-shape. In this way, in the case where the substance layer 400 is formed in a U shape, display quality may be degraded. That is, when the substance layer 400 is a light emitting layer, the light emitting layer may be formed to have a U-shaped outline due to a difference in drying speed between regions and a flow caused thereby, and in this case, the thickness of the light emitting layer may become different in each region, so that the efficiency of the light emitting element may be reduced, and the display quality may be degraded.

However, referring to fig. 1 and 2, in the drying apparatus according to the present embodiment, since the substrate 300 is not in direct contact with the table 100, the coffee ring effect can be prevented. As shown in fig. 2, the drying apparatus according to the present embodiment dries the material layer 400 by the drying gas in the chamber 1000, and thus the evaporation amount of each region of the material layer 400 can be similar. The amount of evaporation is shown by arrows in fig. 2, and as shown in fig. 2, it can be confirmed that evaporation is uniform in all regions.

Fig. 3 shows a drying apparatus in which the substrate 300 is in direct contact with the stage 100. Referring to fig. 3, the substrate 300 is in direct contact with the stage 100. Therefore, when the stage 100 is heated, the heat of the stage 100 is directly transferred to the substrate 300.

Fig. 4 shows a configuration in which the material layer 400 is dried in the drying apparatus of fig. 3. Referring to fig. 4, partition walls 350 may be positioned on a substrate 300, and a substance layer 400 may be positioned between the partition walls 350. The substance layer 400 may be a light emitting layer.

Since the substrate 300 is in direct contact with the stage 100, heat of the stage 100 is directly transferred to the substrate 300. Thus, evaporation occurs more actively at the edge positions of the substance layer 400 and relatively less in the center due to the coffee ring effect. The amount of evaporation is shown by arrows in fig. 4, and it can be confirmed that the evaporation is different in each region.

This causes a flow from the center to the edge position side in the material layer 400 due to the difference in evaporation rate.

Fig. 5 to 7 illustrate the principle of evaporation in the case where the substrate 300 is in direct contact with the stage 100. Referring to fig. 5, the substrate 300 is in direct contact with the stage 100, and the stage 100 is heated. The partition walls 350 are positioned on the substrate 300, and the substance layer 400 is positioned between the partition walls 350.

Fig. 6 shows the flow within the substance layer 400 during drying. Referring to fig. 6, a flow in the direction of the arrow is formed in the substance layer 400. In the central part of the substance layer 400 evaporation occurs relatively little, whereas at the edge positions of the substance layer 400 evaporation occurs more actively. Therefore, the substance layer 400 in the central portion where evaporation occurs less is directed from the center toward the edge position and a flow in such a direction is formed.

Fig. 7 shows the shape of the substance layer 400 before and after evaporation. As shown in fig. 7, the thickness of the substance layer 400 becomes thicker at the edge position portion due to the flow in the direction from the center toward the edge position.

Fig. 8 to 10 illustrate the principle of evaporation in the case where the substrate 300 is not in direct contact with the stage 100. Referring to fig. 8, the substance layer 400 is positioned between the partition walls 350 on the substrate 300, and the substance layer 400 is evaporated by the heated air.

Fig. 9 shows the flow within the substance layer 400 during drying. Referring to fig. 9, evaporation occurs relatively more at a central portion of the substance layer 400 and relatively less at an edge portion of the substance layer 400 without directly heating the substrate 300. The relative magnitude of evaporation is shown by the arrows. As shown in fig. 9, evaporation is actively generated in the central portion of the substance layer 400.

Therefore, the substance layer 400 at the edge position moves toward the central portion of the substance layer 400 where evaporation is actively generated, and a flow in a direction from the edge position of the substance layer 400 toward the center is formed.

Fig. 10 shows the shape of the substance layer 400 before and after evaporation. As shown in fig. 10, the thickness of the substance layer 400 is formed uniformly by the flow in the direction from the edge position toward the center.

That is, in the case where the substrate 300 is not in direct contact with the table 100 as in the drying apparatus according to the present embodiment, the substance layer 400 can be dried from the central portion and a flow from the edge position toward the center is formed, whereby the coffee ring effect can be prevented and a uniform profile can be formed.

Fig. 11 shows the outline of the material layer 400 after drying the material layer 400 while varying the pressure and temperature in the drying device in which the substrate is in direct contact with the stage. The temperature becomes higher in the order of a ℃ < B ℃ < C ℃, and the temperature difference in each section has 10 degrees or more.

Referring to fig. 11, even if the temperature and the pressure are different under various conditions, when the substrate 300 is in direct contact with the stage 100, it can be confirmed that the outline of the material layer 400 has a U-shape. Although the shape of the outline is different by the adjustment of the pressure and the temperature, the outline as a whole is U-shaped even if the pressure and the temperature are different as shown in fig. 11. This is because, as described above, when the substrate 300 is in direct contact with the table 100, a flow is formed in a direction from the center of the substance layer 400 toward the edge position due to the coffee ring effect, and the thickness at the edge position becomes thicker.

Therefore, when the contour of the material layer 400 is U-shaped, the efficiency is reduced. That is, in the case where the material layer 400 is a light emitting layer of a display device, light emitting efficiency may be reduced due to uneven thickness.

However, in the case where the substance layer 400 is dried by a method in which the substrate 300 is not in direct contact with the table 100 as in the present embodiment, the coffee ring effect can be prevented during the drying process, so that a uniform profile can be formed.

Fig. 12 shows the profile of the substance layer 400 after drying in a drying device in which the substrate 300 is in direct contact with the table 100. Referring to fig. 12, in the case where the substrate 300 is in direct contact with the table 100, a U-shaped outline is formed due to the coffee ring effect.

Fig. 13 is a 2D profile of the substance layer 400 having the profile of fig. 12, and fig. 14 shows an element including the substance layer 400 having the profile of fig. 12. Referring to fig. 13, it can be confirmed that the thickness of the material layer 400 is different in each region, and referring to fig. 14, it can be confirmed that the display quality is not uniform, such as the central portion is relatively dark, due to the thickness difference.

Fig. 15 shows the profile of the substance layer 400 after drying in a drying device in which the substrate 300 is not in direct contact with the table 100 according to this embodiment. Referring to fig. 15, in the case where the substrate 300 is not in direct contact with the table 100, it can be confirmed that a flat profile is formed instead of the U-shaped profile.

Fig. 16 is a 2D profile of the substance layer 400 having the profile of fig. 15, and fig. 17 shows an element including the substance layer 400 having the profile of fig. 15. Referring to fig. 16, it is confirmed that the thickness of the material layer 400 is relatively uniform in each region, as compared to fig. 13. Referring to fig. 17, it can be confirmed that the luminance of the entire light emitting element is uniform as compared to fig. 14.

Fig. 18 measured the efficiency (Cd/a) in terms of color coordinates (CIEx) for the display device with the contour of fig. 12 (a) and the display device with the contour of fig. 15 (9679;). Referring to fig. 18, it can be confirmed that the efficiency of the display device having the profile of fig. 15 is more excellent.

Fig. 19 shows a drying device according to another embodiment. Referring to fig. 19, the drying apparatus according to the present embodiment is the same as that of fig. 1 except that it further includes an upper plate 500. Detailed descriptions of the same constituent elements are omitted.

Referring to fig. 19, drying is achieved by both the table 100 located at the lower portion of the substrate 300 and the upper plate 500 located at the upper portion of the substrate 300. That is, the stage 100 and the upper plate 500 are heated, and the substrate 300 is dried at both upper and lower portions. Therefore, the drying speed of the substrate 300 may be improved as compared to the embodiment of fig. 1.

As described above, the drying apparatus according to the present embodiment prevents the substrate 300 from directly contacting the table 100, thereby preventing the coffee ring effect during the drying process and forming a flat profile. Therefore, when a light emitting layer or the like is formed on the substrate 300, the profile of the light emitting layer can be made flat, and light emitting efficiency and display quality can be improved.

The embodiments of the present invention have been described in detail, but the scope of the present invention is not limited thereto, and various modifications and improvements made by those skilled in the art using the basic concept of the present invention defined in the claims also belong to the scope of the present invention.

Claims (17)

1. A drying apparatus, comprising:

a cavity;

a table located within the cavity;

a support part which penetrates the worktable; and

a base plate positioned on the support portion,

in the drying process, the work table is heated,

in the drying process, the substrate is spaced apart from the stage.

2. Drying apparatus according to claim 1,

a substance layer is coated on the upper part of the substrate.

3. Drying apparatus according to claim 2,

the substance layer is applied by an ink-jet method.

4. Drying apparatus according to claim 2,

the material layer is an organic layer.

5. Drying apparatus according to claim 2,

the material layer is one or more layers among layers constituting the light emitting element.

6. Drying apparatus according to claim 1,

the substrate is spaced apart from the table by a distance of 2mm to 150mm.

7. Drying apparatus according to claim 1,

the substrate is spaced apart from the cavity by a distance of 2mm to 150mm.

8. Drying apparatus according to claim 1,

the ratio of the separation distance between the substrate and the stage to the separation distance between the substrate and the chamber is 1.

9. Drying apparatus according to claim 1,

in the drying step, a distance between the substrate and the chamber is larger than a distance between the substrate and the stage.

10. Drying apparatus according to claim 1,

in the drying process, the substrate is spaced apart from the table when the table is lowered.

11. Drying apparatus according to claim 1,

in the drying step, the substrate is spaced apart from the table when the support portion is raised.

12. Drying apparatus according to claim 1,

in the drying step, the stage and the substrate are not in direct contact with each other.

13. Drying apparatus according to claim 1,

the drying gas generated in the drying process flows toward an upper region and a lower region of the substrate.

14. Drying apparatus according to claim 13,

the chamber includes an exhaust port that exhausts the dry gas.

15. The drying apparatus according to claim 1, further comprising:

an upper plate between an upper portion of the substrate and the cavity.

16. Drying apparatus according to claim 15,

in the drying process, the upper plate is heated.

17. Drying apparatus according to claim 15,

the upper plate is not in direct contact with the base plate.

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