阅读说明：本技术 像素界定结构和显示面板及其制备方法、显示装置 (Pixel defining structure, display panel, preparation method of display panel and display device ) 是由 胡春静 侯文军 于 2018-08-31 设计创作，主要内容包括：本公开涉及一种像素界定结构和显示面板及其制备方法、显示装置。像素界定结构包括：具有第一开口的第一像素界定层,位于基板上,所述第一像素界定层包括由第一亲疏材料形成的第一部分和由第二亲疏材料形成的第二部分,所述第一部分和所述第二部分在基板表面上的投影不交叠,所述第一像素界定层面向第一开口的侧面包括由所述第一亲疏材料形成的第一侧面和由所述第二亲疏材料形成的第二侧面,其中,所述第一亲疏材料与所述第二亲疏材料的亲疏性不同。(The disclosure relates to a pixel defining structure, a display panel, a manufacturing method of the pixel defining structure and the display panel, and a display device. The pixel defining structure includes: a first pixel defining layer having a first opening on a substrate, the first pixel defining layer including a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material, projections of the first portion and the second portion on a surface of the substrate do not overlap, a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity.)

1. A pixel defining structure, comprising:

a first pixel defining layer having a first opening on a substrate, the first pixel defining layer including a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material, projections of the first portion and the second portion on a surface of the substrate do not overlap, a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity.

2. The pixel defining structure according to claim 1, wherein the first portion is a lyophilic portion, the second portion is a lyophobic portion, a side of the lyophilic portion near the first opening includes a tooth structure, the lyophobic portion is located between teeth of the tooth structure, and the lyophobic portion does not exceed the lyophilic portion in an extending direction of the teeth.

3. The pixel defining structure according to claim 2, wherein the tooth structure is a rectangular tooth structure, and the first side surface and the second side surface are both rectangular.

4. The pixel defining structure of claim 1, further comprising:

a second pixel defining layer having a second opening on a side of the first pixel defining layer away from the substrate, the second pixel defining layer being formed of the second lyophilic material, a projection of the second pixel defining layer on the substrate surface being completely covered by a projection of the first pixel defining layer on the substrate surface, the second opening corresponding to a position of the first opening, and the projection of the second opening on the substrate surface completely covering a projection of the first opening on the substrate surface.

5. The pixel defining structure of claim 1, wherein the first lyophilic material comprises SiO₂。

6. The pixel defining structure of claim 1, wherein the second lyophilic material comprises a fluoro-lipid material.

7. The pixel defining structure according to claim 1, wherein a slope angle of the side facing the first opening is 30-90 degrees.

8. The pixel defining structure according to claim 1, wherein the first pixel defining layer is a mesh structure having a plurality of first openings, and all sides of the first pixel defining layer facing the first openings comprise a first side formed of the first lyophilic material and a second side formed of the second lyophilic material.

9. The pixel defining structure of claim 1, wherein the first portion and the second portion of the first pixel defining layer are the same height.

10. The pixel defining structure of claim 4, wherein the second portion in the first pixel defining layer and the second lyophilic material in the second pixel defining layer are integral, the second lyophilic material being a lyophobic material.

11. The pixel defining structure according to claim 4, wherein a slope angle of a side of the second pixel defining layer facing the second opening is 30-90 degrees.

12. A display panel comprising a pixel defining structure according to any one of claims 1 to 11.

13. A display device comprising the display panel according to claim 12.

14. A method for preparing a pixel defining structure, comprising:

forming a first pixel defining layer having a first opening on a substrate, the first pixel defining layer including a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material, projections of the first portion and the second portion on a surface of the substrate do not overlap, a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity.

15. A method of making as defined in claim 14, further comprising forming a second pixel defining layer on the first pixel defining layer, wherein forming the first and second pixel defining layers comprises:

forming a first lyophilic and hydrophobic material layer on the substrate;

patterning the first layer of lyophilic material to form the first portion of the first pixel defining layer;

forming a second lyophilic and hydrophobic material layer on the basis of the patterned first lyophilic and hydrophobic material layer;

patterning the second lyophilic material layer to form the second portion of the first pixel defining layer and the second pixel defining layer, wherein the second pixel defining layer has a second opening, a projection of the second pixel defining layer on a substrate surface is completely covered by a projection of the first pixel defining layer on the substrate surface, the second opening corresponds to a position of the first opening, and the projection of the second opening on the substrate surface completely covers a projection of the first opening on the substrate surface.

16. The method of making as defined in claim 14, wherein the first portion is a lyophilic portion, the method further comprising:

determining an area ratio of the first side surface to the second side surface according to a climbing speed of a functional layer to be formed at the first opening at the lyophilic section.

17. The method of manufacturing of claim 16, wherein an area ratio of the first side to the second side is inversely proportional to the climbing speed.

18. A method of manufacturing a display panel, comprising:

a method of making a pixel defining structure according to any one of claims 14 to 17.

19. A manufacturing method according to claim 18, the pixel defining structure enclosing an opening for forming a functional layer, the opening including a first opening, the manufacturing method further comprising: a solution containing the material of the functional layer is formed within the opening using inkjet printing.

Technical Field

The present disclosure relates to the field of display technologies, and in particular, to a pixel defining structure, a display panel, a manufacturing method thereof, and a display device.

Background

With the rapid development of display technology, people have higher and higher requirements on the performance of display products. Display panels have received a great deal of attention as important components of display products.

In the process of manufacturing a display panel, particularly in the process of manufacturing a functional layer film by a wet process such as inkjet printing, it is necessary to remove an excessive solvent by a drying process. The drying process may cause uneven thickness of the formed thin film, thereby affecting the lifetime and display effect of the device.

The related wet process fabrication process employs a dual-layer Pixel Definition Layer (PDL) structure to reduce thickness non-uniformity of the thin film caused by the drying process.

Disclosure of Invention

The related wet preparation process still has difficulty in ensuring the uniformity of the thickness of the formed thin film.

For this reason, the present disclosure proposes a technical solution capable of improving the uniformity of the thickness of a thin film prepared by a wet process.

According to a first aspect of embodiments of the present disclosure, there is provided a pixel defining structure, including: a first pixel defining layer having a first opening on a substrate, the first pixel defining layer including a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material, projections of the first portion and the second portion on a surface of the substrate do not overlap, a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity.

In some embodiments, the first portion is a lyophilic portion, the second portion is a lyophobic portion, a side of the lyophilic portion near the first opening includes a tooth structure, the lyophobic portion is located between teeth of the tooth structure, and the lyophobic portion does not exceed the lyophilic portion in an extending direction of the teeth.

In some embodiments, the tooth form structure is a rectangular tooth form structure, and the first side surface and the second side surface are both rectangular.

In some embodiments, the pixel defining structure further comprises: a second pixel defining layer having a second opening on a side of the first pixel defining layer away from the substrate, the second pixel defining layer being formed of the second lyophilic material, a projection of the second pixel defining layer on the substrate surface being completely covered by a projection of the first pixel defining layer on the substrate surface, the second opening corresponding to a position of the first opening, and the projection of the second opening on the substrate surface completely covering a projection of the first opening on the substrate surface.

In some embodiments, the first lyophilic material comprises SiO₂。

In some embodiments, the second lyophilic material includes a fluoro-lipid material.

In some embodiments, the side facing the first opening has a slope angle of 30 degrees to 90 degrees.

In some embodiments, the first pixel defining layer is a mesh structure having a plurality of first openings, and all sides of the first pixel defining layer facing the first openings comprise a first side formed of the first lyophilic material and a second side formed of the second lyophilic material.

In some embodiments, the first portion and the second portion of the first pixel defining layer are the same height.

In some embodiments, the second portion in the first pixel defining layer and a second lyophilic material in the second pixel defining layer are integral, the second lyophilic material being a lyophobic material.

In some embodiments, a slope angle of a side of the second pixel defining layer facing the second opening is 30-90 degrees.

According to a second aspect of the embodiments of the present disclosure, there is provided a display panel including the aforementioned pixel defining structure.

According to a third aspect of the embodiments of the present disclosure, there is provided a display device including the aforementioned display panel.

According to a fourth aspect of the embodiments of the present disclosure, there is provided a method for manufacturing a pixel defining structure, including: forming a first pixel defining layer having a first opening on a substrate, the first pixel defining layer including a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material, projections of the first portion and the second portion on a surface of the substrate do not overlap, a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity.

In some embodiments, the method of making further comprises forming a second pixel defining layer on the first pixel defining layer, wherein forming the first and second pixel defining layers comprises: forming a first lyophilic and hydrophobic material layer on the substrate; patterning the first layer of lyophilic material to form the first portion of the first pixel defining layer; forming a second lyophilic and hydrophobic material layer on the basis of the patterned first lyophilic and hydrophobic material layer; patterning the second lyophilic material layer to form the second portion of the first pixel defining layer and the second pixel defining layer, wherein the second pixel defining layer has a second opening, a projection of the second pixel defining layer on a substrate surface is completely covered by a projection of the first pixel defining layer on the substrate surface, the second opening corresponds to a position of the first opening, and the projection of the second opening on the substrate surface completely covers a projection of the first opening on the substrate surface.

In some embodiments, the first moiety is a lyophilic moiety, the method of making further comprising: determining an area ratio of the first side surface to the second side surface according to a climbing speed of a functional layer to be formed at the first opening at the lyophilic section.

In some embodiments, the area ratio of the first side to the second side is inversely proportional to the climbing speed.

According to a fifth aspect of the embodiments of the present disclosure, there is provided a method of manufacturing a display panel, including: the preparation method of the pixel definition structure is provided.

In some embodiments, the pixel defining structure encloses an opening for forming a functional layer, the opening comprising a first opening, the method of making further comprising: a solution containing the material of the functional layer is formed within the opening using inkjet printing.

In the above-described embodiment, designing the first pixel defining layer such that the side facing the first opening includes the first side formed of the lyophilic insulating material and the second side formed of the lyophobic insulating material can significantly improve the uniformity of the thickness of the formed thin film.

Other features of the present disclosure and advantages thereof will become apparent from the following detailed description of embodiments of the present disclosure with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the disclosure and together with the description, serve to explain the principles of the disclosure.

The present disclosure may be more clearly understood from the following detailed description, taken with reference to the accompanying drawings, in which:

fig. 1 is a top view illustrating a pixel defining structure according to some embodiments of the present disclosure;

FIG. 1A is a top view of a portion of the pixel defining structure shown in FIG. 1;

FIGS. 1B and 1C are cross-sectional views of a pixel defining structure taken along lines AA 'and BB', respectively, in the top view shown in FIG. 1A;

FIG. 1D is a cross-sectional view of the pixel defining structure taken along line CC' in the cross-sectional view shown in FIG. 1B;

FIG. 2A is a top view illustrating pixel definition structures according to further embodiments of the present disclosure;

FIGS. 2B and 2C are cross-sectional views of the pixel defining structure taken along lines aa 'and bb', respectively, in the top view shown in FIG. 2A;

FIG. 2D is a cross-sectional view of the pixel defining structure taken along the line cc' in the cross-sectional view shown in FIG. 2B;

FIG. 3A is a top view illustrating a pixel defining structure according to still further embodiments of the present disclosure;

FIGS. 3B and 3C are cross-sectional views of the pixel defining structure taken along lines AA 'and BB' in FIG. 3A, respectively;

FIG. 3D is a cross-sectional view of the pixel defining structure taken along line CC' in FIG. 3B;

fig. 4A is a flow chart illustrating a method of fabricating a pixel defining structure according to some embodiments of the present disclosure;

FIG. 4B is a flow chart illustrating a method of fabricating a pixel defining structure according to further embodiments of the present disclosure;

FIG. 5 is a flow chart illustrating a method of making a display panel according to some embodiments of the present disclosure;

FIG. 6 is a cross-sectional view illustrating a first layer of lyophilic material after it is formed, according to some embodiments of the present disclosure;

fig. 7A is a top view illustrating a first layer of lyophilic material after patterning it according to some embodiments of the present disclosure;

FIG. 7B is a cross-sectional view of the pixel defining structure taken along line AA' in FIG. 7A;

FIG. 8 is a cross-sectional view illustrating after forming a second layer of lyophilic material according to some embodiments of the present disclosure;

fig. 9A and 9B are graphs showing thickness profiles of the functional layer in the longitudinal direction L and the transverse direction T, respectively, in one pixel unit;

fig. 10A, 10B show thickness profiles of a functional layer in a longitudinal direction L and a transverse direction T, respectively, within one pixel unit according to some embodiments of the present disclosure.

It should be understood that the dimensions of the various parts shown in the figures are not drawn to scale. Further, the same or similar reference numerals denote the same or similar components.

Detailed Description

Various embodiments of the present disclosure will now be described in detail with reference to the accompanying drawings. The description of the embodiments is merely illustrative and is in no way intended to limit the disclosure, its application, or uses. The present disclosure may be embodied in many different forms and is not limited to the embodiments described herein. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. It should be noted that: the relative arrangement of parts and steps set forth in these embodiments is to be construed as illustrative only and not as a limitation unless specifically stated otherwise.

The use of "first," "second," and similar terms in this disclosure is not intended to indicate any order, quantity, or importance, but rather are used to distinguish one element from another. The word "comprising" and similar words mean that the elements preceding the word encompass the elements listed after the word, and does not exclude the possibility that other elements are also encompassed. "upper", "lower", "left", "right", and the like are used merely to indicate relative positional relationships, and when the absolute position of the object being described is changed, the relative positional relationships may also be changed accordingly.

In the present disclosure, when a specific element is described as being located between a first element and a second element, there may or may not be intervening elements between the specific element and the first element or the second element.

All terms (including technical or scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs unless specifically defined otherwise. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

According to some embodiments of the present disclosure, a pixel defining structure includes a first pixel defining layer having a first opening. The first pixel defining layer is located on the substrate. The first pixel defining layer includes a first portion formed of a first lyophilic material and a second portion formed of a second lyophilic material. The projections of the first and second portions on the substrate surface do not overlap. The side of the first pixel defining layer facing the first opening includes a first side formed of a first lyophilic material and a second side formed of a second lyophilic material. The first lyophilic material and the second lyophilic material have different lyophobicity.

According to still further embodiments of the present disclosure, the pixel defining structure further includes a second pixel defining layer having a second opening. The second pixel defining layer is positioned on one side of the first pixel defining layer far away from the substrate and is formed by a second hydrophilic and hydrophobic material. The projection of the second pixel defining layer on the substrate surface is completely covered by the projection of the first pixel defining layer on the substrate surface, the second opening corresponds to the position of the first opening, and the projection of the second opening on the substrate surface completely covers the projection of the first opening on the substrate surface.

Fig. 1 is a top view illustrating a pixel defining structure according to some embodiments of the present disclosure.

Fig. 1 illustrates the distribution of first and second pixel defining layers PDL1, PDL2 in the longitudinal direction L and the transverse direction T on the substrate 100.

Fig. 1A is a top view of a portion of the pixel defining structure shown in fig. 1, including two pixel defining units. Fig. 1B and 1C are cross-sectional views of the pixel defining structure taken along lines AA 'and BB' in fig. 1A, respectively. Fig. 1D is a cross-sectional view of the pixel defining structure taken along line CC' in fig. 1B.

Fig. 1A illustrates a distribution of the first and second pixel defining layers PDL1, PDL2 in the longitudinal direction L on the substrate 100. As shown in fig. 1B, the first pixel definition layer PDL1 has a first opening 110, and the second pixel definition layer PDL2 has a second opening 210. The second opening 210 corresponds to the position of the first opening 110, and the projection of the second opening 210 on the substrate surface completely covers the projection of the first opening 110 on the substrate surface. For example, the second opening 210 corresponds to the first opening 110 in position and substantially overlaps the center, and the second opening 210 is larger than the first opening 110.

The sides of the first pixel defining layer PDL1 facing the first opening 110 include a first side SF1 and a second side SF2, as shown in fig. 1B and 1C, respectively. Projections P1 and P2 of the first side SF1 and the second side SF2 on the surface of the substrate 100 do not intersect as shown in fig. 1D. First side SF1 is formed from a first lyophilic material (e.g., lyophilic material) and second side SF2 is formed from a second lyophilic material (e.g., lyophobic material). In some embodiments, the lyophilic material includes SiO₂The lyophobic material comprises fluorine grease material.

As shown in fig. 1B and 1C, a first pixel defining layer PDL1 is located on the substrate 100. The projection of the second pixel defining layer PDL2 on the substrate surface is completely covered by the projection of the first pixel defining layer PDL1 on the substrate surface. For example, the second pixel definition layer PDL2 partially overlaps the first pixel definition layer PDL 1.

As shown in fig. 1C, the first pixel defining layer PDL1 includes a first portion (e.g., lyophilic portion) 120 formed of a first lyophilic material and a second portion (e.g., lyophobic portion) 130 formed of a second lyophilic material. In some embodiments, the first portion 120 and the second portion 130 are the same height. As shown in fig. 1D, the projections of the first portion 120 and the second portion 130 on the substrate surface do not overlap.

The second pixel defining layer PDL2 is formed of a second lyophilic material, for example, the same type of second lyophilic material as PDL 1. In some embodiments, the second lyophilic material in the second pixel defining layer PDL2 is integral with the second lyophilic material in the second portion 130 of the first pixel defining layer PDL1, e.g., both are lyophobic materials. The PDL2 is formed of a lyophobic material or includes a lyophobic material on its surface, and can prevent overflow during the process of preparing a functional layer using a wet process, thereby effectively preventing cross color between adjacent pixels.

Fig. 1D illustrates a cross-sectional view of the first pixel definition layer PDL1 taken along the line CC' in the cross-sectional view illustrated in fig. 1B. The first portion 120 is a lyophilic portion and the second portion 130 is a lyophobic portion. The lyophilic sections 120 include a tooth-shaped structure on a side thereof adjacent to the first opening 110. The lyophobic parts 130 are located between the teeth of the tooth structure. The lyophobic parts 130 do not go beyond the lyophilic parts 120 in the extending direction of the teeth. As shown in fig. 1D, projections P1 and P2 of the side facing the first opening on the surface of the base plate 100 are tooth-shaped, wherein the lyophilic sections 120 are longer than the lyophobic sections 130 in the extending direction of the teeth. In some embodiments, the tooth form structure is a rectangular tooth form structure. Fig. 1D shows that the side of the first pixel definition layer PDL1 facing the first opening 110 is rectangular and toothed, wherein the first side SF1 and the second side SF2 are both rectangular.

In other embodiments, the side of the first pixel definition layer PDL1 facing the first opening 110 is planar. That is, the first side surface and the second side surface are coplanar, and projections of the first side surface and the second side surface on the surface of the substrate 100 are linear.

Fig. 2A is a top view illustrating pixel definition structures according to further embodiments of the present disclosure. Fig. 2B and 2C are cross-sectional views of the pixel defining structure taken along lines aa 'and bb' in fig. 2A, respectively. Fig. 2D is a cross-sectional view of the pixel defining structure taken along line cc' in fig. 2B.

Fig. 2A illustrates a second pixel defining layer PDL2' and the substrate 100. As shown in fig. 2B, the first pixel defining layer PDL1 'has a first opening 110', and the second pixel defining layer PDL2 'has the same opening as the first pixel defining layer PDL 1'.

The sides of the first pixel definition layer PDL1 'facing the first opening 110' include a first side SF1 'and a second side SF2', as shown in fig. 2B and 2C, respectively. As shown in fig. 2B and 2C, the second pixel defining layer PDL2 'completely covers the first pixel defining layer PDL 1'. Similar to fig. 1C, the first pixel defining layer PDL1' in fig. 2C also includes lyophilic and lyophobic portions 120' and 130', except that the ratio of the volume of the lyophobic portion to the lyophilic portion is greater.

Fig. 2D illustrates a cross-sectional view of the first pixel defining layer PDL1 'taken along the line cc' in the cross-sectional view illustrated in fig. 2B. As shown in fig. 2D, projections P1 'and P2' of the first side SF1 'and the second side SF2' on the surface of the substrate 100 are linear, i.e., the first side and the second side are coplanar.

In some embodiments, the first pixel defining layer and the second pixel defining layer are both mesh structures having a plurality of openings. For example, the first pixel defining layer is a mesh structure having a plurality of first openings, and all sides of the first pixel defining layer facing the first openings include a first side formed of a first lyophilic material and a second side formed of a second lyophilic material. The second pixel defining layer is a mesh structure having a plurality of second openings.

The slope angle of the side of the first pixel defining layer facing the first opening may be in the range of 30-90 degrees. The slope angle of the side surface of the second pixel defining layer facing the second opening is 30-90 degrees.

Fig. 3A is a top view illustrating a pixel defining structure according to still further embodiments of the present disclosure. Fig. 3A is the same as the top view shown in fig. 1A, and therefore like reference numerals are used to denote similar structures. Fig. 3B and 3C are cross-sectional views of the pixel defining structure taken along lines AA 'and BB' in fig. 3A, respectively. Fig. 3D is a cross-sectional view of the pixel defining structure taken along line CC' in fig. 3B. The cross-sectional views shown in fig. 3B and 1B are also the same. For the same parts, which are not repeated, different fig. 3C and 3D will be described in detail below.

Unlike fig. 1C, only the lyophobic portion 130 "of the first pixel defining layer PDL 1" is visible from fig. 3C, and the lyophilic portion 120 "of the first pixel defining layer PDL 1" is not visible.

Fig. 3D is a cross-sectional view of the first pixel defining layer PDL1 ″ taken along the line CC' in fig. 3B. As shown in fig. 3D, the lyophilic sections 120 "and the lyophobic sections 130" are bar-shaped structures alternately arranged, wherein the lyophilic sections 120 "are longer than the lyophobic sections 130" in the extending direction of the bars. Similar to fig. 1D, projections P1 and P2 of the side of the first pixel defining layer PDL1 ″ facing the first opening on the surface of the substrate 100 are also tooth-shaped.

Fig. 4A is a flow chart illustrating a method of making a pixel defining structure according to some embodiments of the present disclosure. Steps S1-S2 of FIG. 4A are described below in conjunction with FIGS. 1A-1D and 2A-2D.

In step S1, a first pixel defining layer having a first opening is formed on the substrate, such as the first pixel defining layer shown in fig. 1D and 2D. As described above, the first pixel defining layer includes the first portion and the second portion, projections of the first portion and the second portion on the substrate surface do not overlap, and a side of the first pixel defining layer facing the first opening includes a first side formed of the first lyophilic material and a second side formed of the second lyophilic material, wherein the first lyophilic material and the second lyophilic material have different lyophobicity. The first opening is used for forming a functional layer.

In step S2, a second pixel defining layer is formed over the first pixel defining layer, such as the structures shown in FIGS. 1A-1C and 2A-2C. As described above, the second pixel defining layer has the second opening. The projection of the second pixel defining layer on the substrate surface is completely covered by the projection of the first pixel defining layer on the substrate surface. The second opening corresponds to the first opening in position, and the projection of the second opening on the substrate surface completely covers the projection of the first opening on the substrate surface.

In some embodiments, the method of making a pixel defining structure further comprises: step S3, determining an area ratio of the first side surface to the second side surface according to a climbing speed of the functional layer to be formed at the first opening at the first portion (i.e., the lyophilic portion). Step S3 will be described later in conjunction with fig. 5.

Fig. 4B is a flow chart illustrating methods of fabricating pixel definition structures according to further embodiments of the present disclosure. Steps S11-S14 in FIG. 4B are described below in conjunction with FIGS. 6-8. Fig. 6 illustrates a cross-sectional view after forming a first layer of lyophilic material according to some embodiments of the present disclosure. Fig. 7A is a top view illustrating a first layer of lyophilic material after patterning it according to some embodiments of the present disclosure; fig. 7B is a cross-sectional view of the pixel defining structure taken along line AA' in fig. 7A. Fig. 8 is a cross-sectional view illustrating after forming a second layer of lyophilic material according to some embodiments of the present disclosure.

In step S11, a first lyophilic material layer 300 is formed on the substrate 100, forming the structure shown in fig. 6. In some embodiments, the first layer of lyophilic material is formed by a spin-on or evaporation process. As previously mentioned, the first layer of lyophilic material may comprise SiO₂。

In step S12, the first lyophilic material layer 300 is patterned to form a first portion (e.g., lyophilic portion) of the first pixel defining layer, such as the structure shown in fig. 7A and 7B. The patterned first lyophilic material layer 300 includes a tooth structure on a side thereof adjacent to the opening 310. As shown in fig. 7A, the projection of the side of the first lyophilic-lyophobic material layer 300 facing the opening 310 on the substrate 100 is in a tooth shape. That is, the side of the first lyophilic and hydrophobic material layer facing the opening is a surface where the protrusions 310P and the recesses 310C are alternately arranged. In some embodiments, the patterning process includes a photolithography process, such as exposing and developing the first lyophilic and hydrophobic material layer with a mask to form the first lyophilic and hydrophobic material layer with teeth.

In step S13, a second lyophilic material layer 400 is formed on the basis of the patterned first lyophilic material layer 300, forming a structure such as that shown in fig. 8. As shown in fig. 8, a portion of the second lyophilic material layer 400 fills the opening 310, and another portion covers the first lyophilic material layer 300 (lyophilic portion of the first pixel defining layer). In some embodiments, the second layer of lyophilic material is formed by a spin-on or evaporation process. As previously mentioned, the second layer of lyophilic material may include a fluoro-lipid material.

In step S14, the second lyophilic material layer 400 is patterned to form a first opening and a second opening at corresponding positions of the opening 310, so as to form a first pixel defining layer having the first opening and a second pixel defining layer having the second opening, for example, to form a structure as shown in fig. 1B or 2B. In fig. 1B and 2B, the projection of the second opening on the substrate surface completely covers the projection of the first opening on the substrate surface. Specifically, FIG. 1B shows that the second opening is larger than the first opening; and figure 2B shows that the second opening is substantially the same size as the first opening. As described previously, the side of the first pixel defining layer facing the first opening includes the first side formed of the first lyophilic material and the second side formed of the second lyophilic material.

A patterning process similar to that in step S12, for example, exposure development of the second lyophilic material using a mask, may be employed in step S14, except that a different mask is employed than that in step S12. Different first and second openings may be formed using different masks, so that different first and second pixel defining layers may be formed.

In some embodiments, a mask is used to form the first pixel definition layer PDL1 and the second pixel definition layer PDL2 shown in fig. 1A-1D, where the second opening 210 is larger than the first opening 110 and the second pixel definition layer PDL2 partially covers the first pixel definition layer PDL 1.

In other embodiments, another mask is used to form the first pixel definition layer PDL1 'and the second pixel definition layer PDL2' as shown in fig. 2A-2D, wherein the second opening 210 'is equal to the first opening 110', and the second pixel definition layer PDL2 'completely covers the first pixel definition layer PDL 1'.

According to an embodiment of the present disclosure, a display panel including the aforementioned pixel defining structure and a method for manufacturing the same are also provided.

Fig. 5 is a flowchart illustrating a method of manufacturing a display panel according to further embodiments of the present disclosure. Steps S11, S12, S13, S14 in fig. 5 are similar to the corresponding steps in fig. 4B, and thus the description will not be repeated below, and only steps S21, S22, and S3 are described in detail.

In step S21, a solution containing a functional layer material is formed in the opening by a wet process, the pixel defining structure encloses an opening for forming the functional layer, the opening includes a first opening. In some embodiments, the wet process comprises an inkjet printing process. In forming a solution containing a functional layer material by inkjet printing, an ink may be formed by dissolving the corresponding functional layer material as a solute in an aromatic solvent.

The functional layer is, for example, a light-emitting layer, a hole-injecting layer, a hole-transporting layer or an electron-blocking layer. As an example, the following materials may be selected for each functional layer. For example, the material of the light-emitting layer may be selected from, for example, poly (p-styrene), polythiophene, polyfluorene, and the like. PEDOT/PSS (doped polyaniline) can be selected as the material of the hole transport layer. The material of the electron blocking layer can be selected from Ir (ppz)3(Tris (phenylpyrazole) iridium; tris (1-base pyrazole) iridium).

In step S22, the solution containing the functional layer material is subjected to a drying process. In some embodiments, the solution is dried in a vacuum chamber, for example, by vacuuming. According to different functional layer materials, after drying by adopting different parameters (such as temperature, time, vacuum degree and the like), the corresponding functional layer can be obtained at the position corresponding to the first opening. The thickness uniformity of these functional layers as an integral part of the pixel will significantly affect the display effect. Each pixel unit is located in one first opening.

After obtaining the respective functional layers, the thicknesses of the functional layers in different directions can be measured. Fig. 9A and 9B show thickness distributions of the functional layer in the longitudinal direction L and the transverse direction T in one pixel unit, respectively, where the horizontal axis represents the width of the pixel unit (i.e., the pixel width) and the vertical axis represents the thickness of the functional layer (i.e., the film thickness). The first pixel defining layer employed in fig. 9A, 9B is composed of only a hydrophilic material.

According to the light emission principle of a light emitting device (e.g., OLED), it is desirable that the functional layer has a uniform thickness over the entire pixel width, which is equal to the design thickness. Namely, it is desirable that: the width corresponding to the functional layer with an actual thickness within a design tolerance (also referred to as an actual width) is as large as possible as the design width, and the design tolerance means that a difference between the actual thickness and the design thickness is tolerable within a certain range. Functional layers with actual thicknesses within design tolerances are considered flat and can be used to calculate the actual width.

FIGS. 9A and 9B show a pixel having a design width L in the longitudinal direction L and the transverse direction T, respectively₀And T₀Actual width is L₁And T₁With a design tolerance of 10 nm. From the data of FIGS. 9A and 9B, L can be calculated₁/L₀＝82％，T₁/T₀73%. Such results indicate that: the thickness uniformity is low in both the longitudinal direction L and the transverse direction T, and the thickness uniformity in the transverse direction T is lower than the thickness uniformity in the longitudinal direction L, i.e., T₁/T₀<L₁/L₀。

In the foregoing embodiment, by designing the first pixel defining layer such that the side facing the first opening includes the first side formed of the first lyophilic material and the second side formed of the second lyophilic material, the uniformity of the thickness of the formed thin film can be significantly improved, for example, L can be achieved₁/L₀≈90％，T₁/T₀About 85% and makes the thickness uniformity in the longitudinal direction L and the transverse direction T close, i.e. L₁/L₀Is closer to T₁/T₀。

In other embodiments, the thickness uniformity of the functional layer may be further improved by adjusting the area ratio of the first side to the second side. The obtained thickness uniformity of the functional layer can reflect the climbing speed of the functional layer to be formed at the opening at the lyophilic part. Thereby, the area ratio of the first side face to the second side face can be determined in step S3 according to the climbing speed of the functional layer to be formed at the opening at the lyophilic section.

For example, if the measured resultIs T₁/T₀<L₁/L₀That is, the thickness uniformity in the transverse direction T is lower than the thickness uniformity in the longitudinal direction L, the area ratio of the first surface and the second surface of the first pixel defining layer facing the first opening in the transverse direction T can be reduced to redistribute the surface tension of the solution during the drying process, so that the solute migration effects in the longitudinal direction and the transverse direction are consistent, and the T is achieved as much as possible₁/T₀＝L₁/L₀. In this case, the area of the first surface may be reduced or the area of the second surface may be increased, or both the area of the first surface and the area of the second surface may be reduced.

Taking the first side and the second side of fig. 1-1D as rectangular teeth as an example, the width of the rectangular teeth can be reduced without changing the shape of the opening, so that the area of the first side at the top of the rectangular teeth will be reduced, and the area of the second side at the root of the rectangular teeth will be increased accordingly. In addition, the first pixel definition layer is in the shape of a rectangular tooth, so that a drainage effect is realized on the solution, and the appearance of the functional layer can be further controlled.

Similarly, if the measured result is T₁/T₀>L₁/L₀That is, the thickness uniformity in the transverse direction T is greater than the thickness uniformity in the longitudinal direction L, the thickness uniformity T can be achieved as much as possible by reducing the area ratio of the first surface and the second surface of the first pixel defining layer facing the first opening in the longitudinal direction L₁/T₀＝L₁/L₀。

According to some embodiments of the present disclosure, the area ratio of the first side to the second side is inversely proportional to the climbing speed. That is, the faster the functional layer material climbs over the lyophilic section of the first pixel defining layer in a certain direction, the smaller the area ratio of the first side surface to the second side surface in that direction is adjusted. By reducing the area ratio of the first surface of the first pixel defining layer facing the first opening to the second surface in the longitudinal direction L or the transverse direction T, the climbing of the functional layer material on the side of the first pixel defining layer can be reduced, thereby further increasing L₁/L₀Or T₁/T₀E.g. can reach L₁/L₀≈T₁/T₀≈90％。

Fig. 10A, 10B show thickness profiles of a functional layer in a longitudinal direction L and a transverse direction T, respectively, within one pixel unit according to some embodiments of the present disclosure. According to the data of FIGS. 10A and 10B, again taking the design tolerance of 10nm as an example, the actual widths in the longitudinal direction L and the transverse direction T are L respectively₁≈115μm，T₁≈70μm。

Comparing fig. 10A and 10B, it can also be seen that: in the longitudinal direction L, climbing of the functional layer material on the side of the first pixel defining layer is relatively obvious; in the transverse direction T, the accumulation of functional layer material in the middle region of the pixel unit is relatively obvious.

In particular, the lyophilic material on the first side plays a more important role than the lyophobic material on the second side in the longitudinal direction L, i.e. the attraction to the solute is greater than the repulsion on both sides of the pixel cell (the sides of the first pixel defining layer), resulting in the solute climbing over the sides. In contrast in the transverse direction T, the lyophobic material on the second side plays a more important role than the lyophilic material on the first side, i.e. the rejection of solutes is greater than the attraction on both sides of the pixel cell, resulting in the solutes being rejected by the sides and thus accumulating in the middle area away from the sides.

Such results indicate that: the solute transport of the functional layer material is not uniform in the longitudinal direction L and the transverse direction T. In this case, the width L may be designed according to the pixel in the longitudinal direction L and the lateral direction T₀And T₀To determine the uniformity of the thickness of the functional layer in the longitudinal direction L and the transverse direction T and thus to determine in which direction the solute transport needs to be adjusted so that the solute transport effects in the different directions are consistent.

For example, if L₀≈135μm，T₀Approximately equal to 80 μm, L can be calculated₁/L₀≈85％，T₁/T₀About 87.5%. I.e. the thickness uniformity in the transverse direction T is greater than the thickness uniformity in the longitudinal direction L, T₁/T₀>L₁/L₀. Thus, the solute transport effect in the longitudinal direction L can be adjusted, for example, the attraction effect of the lyophilic material in the longitudinal direction L can be reduced,Increasing the repellency of the lyophobic material. That is, the area ratio of the first surface of the first pixel defining layer facing the first opening to the second surface in the longitudinal direction L can be reduced to as small as possible T₁/T₀＝L₁/L₀And tends to coincide with solute transport in the transverse direction T.

On the contrary, if L₀≈128μm，T₀Approximately equal to 80 μm, L can be calculated₁/L₀≈90％，T₁/T₀About 87.5%. I.e. the thickness uniformity in the transverse direction T is lower than the thickness uniformity in the longitudinal direction L, T₁/T₀<L₁/L₀. Thus, the solute transport effect in the transverse direction T can be adjusted, for example, in the transverse direction T, reducing the repulsive effect of lyophobic materials, increasing the attractive effect of lyophilic materials. The area ratio of the first surface and the second surface of the first pixel defining layer facing the first opening in the transverse direction T can be increased to redistribute the surface tension of the solution during drying, so that the solute migration in the transverse direction T is consistent with that in the longitudinal direction L to achieve T as much as possible₁/T₀＝L₁/L₀。

Determining the area ratio of the first surface to the second surface also requires consideration of a plurality of factors such as the composition of the solution, the material of the first pixel defining layer, and the slope angle of the side surface. In some embodiments, a slope angle of a side of the first pixel defining layer facing the first opening is in a range of 30-90 degrees.

In the pixel defining structure in which the lyophilic portion of the first pixel defining layer PDL1 includes the tooth structure on the side close to the first opening, the area ratio of the first surface to the second surface may also be reflected by the size of the tooth. The size of the teeth may be determined according to the resolution of the display panel being formed. The resolution of the display panel determines the pixel size (i.e., the size of the first opening) and the pitch, i.e., the structure of the pixel definition layer, e.g., the size of the pixel definition cells (i.e., PDL 1). The determination of the tooth size is described below using the long side as an example. For example, assume a pixel pitch of P and a pixel long dimension of D_pThen the size of the pixel definition cell PDL1 is D₁＝P-D_p. Suppose that a wet process is being utilizedProcess for Forming solutions containing functional layer materials, the minimum dimension of PDL2 to ensure No flooding is D₂And the angles of inclination of PDL1 and PDL2 facing the opening are both 90 degrees, the maximum size of the tooth is (D)₁-D₂)/2。

For example, for a display panel with a maximum resolution of 160ppi (pixels per inch), taking the long side as an example, assuming that the pixel size and pitch are 120 μm and 160 μm, respectively, the cell size of the PDL1 is 40 μm. Assuming that the minimum size of PDL2 ensuring no overflow is 20 μm and the slope angles of PDL1 and PDL2 facing the opening are both 90 degrees when forming a solution containing a functional layer material by inkjet printing, the maximum size of the teeth is (40-20)/2 ═ 10 μm.

The adjustable size range (i.e., the range from zero to the maximum size) of the teeth in the pixel definition layer PDL1 for different resolutions may be different. The higher the resolution, the larger the adjustable size range of the teeth.

It can also be seen from the above that the adjustable size range of the teeth in PDL1 also depends on the size of the angle of slope of the PDL1 and PDL2 facing the opening. In addition, the minimum size of PDL2 that ensures no overflow is different for different wet processes for making functional layer materials. That is, the adjustable size range of the teeth in the PDL1 also depends on the wet process employed.

According to the embodiment of the disclosure, a display device comprising the display panel is also provided. In some embodiments, the display device may be: any product or component with a display function, such as a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

Thus, various embodiments of the present disclosure have been described in detail. Some details that are well known in the art have not been described in order to avoid obscuring the concepts of the present disclosure. It will be fully apparent to those skilled in the art from the foregoing description how to practice the presently disclosed embodiments.

Although some specific embodiments of the present disclosure have been described in detail by way of example, it should be understood by those skilled in the art that the foregoing examples are for purposes of illustration only and are not intended to limit the scope of the present disclosure. It will be understood by those skilled in the art that various changes may be made in the above embodiments or equivalents may be substituted for elements thereof without departing from the scope and spirit of the present disclosure. The scope of the present disclosure is defined by the appended claims.