阅读说明：本技术 微发光二极管显示面板及制备方法 (Micro light-emitting diode display panel and preparation method thereof ) 是由 韦冬 李庆 于波 顾杨 于 2020-12-14 设计创作，主要内容包括：本发明揭示了一种微发光二极管显示面板及制作方法,所述微发光二极管显示面板包括：衬底；微发光二极管阵列,所述微发光二极管阵列设置于所述衬底一侧的表面上,所述微发光二极管真理中,任意相邻的微发光二极管之间具有隔离槽；多个隔离柱,每一隔离柱位于对应的隔离槽中；以及遮光结构,所述遮光结构形成于对应的隔离柱的顶面及侧面；其中,所述顶面朝向所述微发光二极管的发光面,所述侧面围绕所述顶面设置。(The invention discloses a micro light-emitting diode display panel and a manufacturing method thereof, wherein the micro light-emitting diode display panel comprises: a substrate; the micro light-emitting diode array is arranged on the surface of one side of the substrate, and in the micro light-emitting diode real condition, an isolation groove is formed between any adjacent micro light-emitting diodes; a plurality of isolation columns, each isolation column being located in a corresponding isolation slot; the shading structures are formed on the top surfaces and the side surfaces of the corresponding isolation columns; the top surface faces the light emitting surface of the micro light emitting diode, and the side surface is arranged around the top surface.)

1. A micro light emitting diode display panel, comprising:

a substrate;

the micro light-emitting diode array is arranged on the surface of one side of the substrate, and in the micro light-emitting diode real condition, an isolation groove is formed between any adjacent micro light-emitting diodes;

a plurality of isolation columns, each isolation column being located in a corresponding isolation slot; and

the shading structures are formed on the top surfaces and the side surfaces of the corresponding isolation columns;

the top surface faces the light emitting surface of the micro light emitting diode, and the side surface is arranged around the top surface.

2. The micro led display panel of claim 1, further comprising a low surface energy functional layer on the substrate, the low surface energy functional layer being disposed on a surface of the micro led array on a side away from the substrate, the low surface energy functional layer having a groove corresponding to the isolation groove, wherein the isolation pillar protrudes from the substrate through the groove.

3. The micro light-emitting diode display panel of claim 2, wherein the low surface energy functional layer is selected from a silicon dioxide functional layer, a silicon nitride functional layer, or an aluminum oxide functional layer.

4. The micro led display panel of claim 2, wherein the grooves are formed by a patterning process.

5. The micro light-emitting diode display panel of claim 2, wherein the size of the trench is smaller than the size of the isolation trench.

6. A manufacturing method of a micro light emitting diode display panel is characterized by comprising the following steps:

s1, providing a substrate, wherein the surface of one side of the substrate comprises a micro light-emitting diode array, the micro light-emitting diode array comprises a plurality of micro light-emitting diodes, and an isolation groove is arranged between any two micro light-emitting diodes;

s2, forming an isolation layer on the substrate, wherein the isolation layer covers the micro light-emitting diode array, the isolation layer is patterned to form a plurality of isolation columns, and each isolation column is located in a corresponding isolation groove; and

and S3, forming a shading structure on the isolation columns, wherein the shading structure covers the top surfaces and the side surfaces of the isolation columns.

7. The method of claim 6, wherein the step of forming a light shielding structure on the spacers at S3 further comprises:

s31, forming a shading material layer on the substrate to cover the micro light-emitting diode array and the isolation columns;

s32, patterning the shading material layer, removing the part of the shading material layer corresponding to the micro light-emitting diode, and forming a shading structure covering the isolation column.

8. The method of manufacturing according to claim 6, wherein the forming between the isolation layers in S2 further includes:

forming a low surface energy functional layer on the substrate, wherein the low surface energy functional layer covers the micro light-emitting diode array; and

and patterning the low-surface-energy functional layer to form a plurality of grooves, wherein the grooves correspond to the isolation grooves one to one.

9. The method according to claim 8, wherein the low surface energy functional layer is selected from a silicon dioxide functional layer, a silicon nitride functional layer, or an aluminum oxide functional layer.

10. The method of claim 8, wherein the step S3 further includes:

forming a shading material layer on the substrate and covering the low surface energy functional layer and the isolation columns; and

and heating and curing, wherein the shading material is gathered towards the isolation column to form a shading structure covering the isolation column.

Technical Field

The invention relates to a display panel of a micro light-emitting diode and a preparation method thereof.

Background

A Micro Light Emitting Diode Display (μ LED) is a new generation Display panel using a Micro LED as a Light Emitting element of a Display. The technology is to thin, miniaturize and array the LEDs to a single LED with the size of 1-10 μm, transfer the μ LEDs to a circuit substrate in batch mode, and form a μ LED panel required by a micro light-emitting diode display together with electrodes, transistors, an upper electrode, a protective layer and the like on the circuit substrate after surface adhesion.

Currently, the colorization of Micro light emitting diode (Micro LED) display panels generally includes: r, G, B Micro LED chips with different colors are placed in one pixel of the display panel; or three blue Micro LED chips are placed in one pixel of the display panel, and R, G quantum dot layers are arranged on two of the blue Micro LED chips for color conversion, so that colorized display of the Micro LED display panel is realized.

In addition, the pixel structure further comprises a light shielding structure, wherein the light shielding structure is arranged between any two Micro LED chips and used for avoiding light crosstalk in the pixel structure. Since the Micro LED chips and/or the quantum layer are thick, and the Gap between any two Micro LED chips is small, the light shielding structure needs to be a tall and narrow structure.

The existing method for forming the light shielding structure is to design a layer of thicker photoresist on a substrate, and then obtain the light shielding structure by means of exposure and development. Due to the light absorption of the photoresist, light cannot reach the bottom of the photoresist in the exposure process, so that incomplete etching of the photoresist is easily caused, and a high and narrow light shielding structure is not easily obtained.

Disclosure of Invention

The invention aims to provide a micro light-emitting diode display panel and a manufacturing method thereof, which adopt a mode of combining an isolation column and a shading structure to overcome the problem that the existing micro light-emitting diode display panel manufacturing process cannot obtain a high and narrow shading structure.

In order to achieve one of the above objects, an embodiment of the present invention provides a micro light emitting diode display panel, including: a substrate; the micro light-emitting diode array is arranged on the surface of one side of the substrate, and in the micro light-emitting diode real condition, an isolation groove is formed between any adjacent micro light-emitting diodes; a plurality of isolation columns, each isolation column being located in a corresponding isolation slot; the shading structures are formed on the top surfaces and the side surfaces of the corresponding isolation columns; the top surface faces the light emitting surface of the micro light emitting diode, and the side surface is arranged around the top surface.

As an optional technical solution, the substrate further includes a low surface energy functional layer, the low surface energy functional layer is disposed on a surface of the micro light emitting diode array on a side away from the substrate, the low surface energy functional layer has a slot corresponding to the isolation slot, and the isolation pillar protrudes from the slot out of the substrate.

As an optional technical solution, the low surface energy functional layer is selected from a silicon dioxide functional layer, a silicon nitride functional layer or an aluminum oxide functional layer.

As an alternative solution, the trenches are formed by a patterning process.

As an optional technical solution, the size of the slot is smaller than the size of the isolation slot.

The invention also provides a manufacturing method of the micro light-emitting diode display panel, which comprises the following steps:

s1, providing a substrate, wherein the surface of one side of the substrate comprises a micro light-emitting diode array, the micro light-emitting diode array comprises a plurality of micro light-emitting diodes, and an isolation groove is arranged between any two micro light-emitting diodes;

s2, forming an isolation layer on the substrate, wherein the isolation layer covers the micro light-emitting diode array, the isolation layer is patterned to form a plurality of isolation columns, and each isolation column is located in a corresponding isolation groove; and

and S3, forming a shading structure on the isolation columns, wherein the shading structure covers the top surfaces and the side surfaces of the isolation columns.

As an optional technical solution, the forming of the light shielding structure on the plurality of isolation pillars by S3 further includes:

s31, forming a shading material layer on the substrate to cover the micro light-emitting diode array and the isolation columns;

s32, patterning the shading material layer, removing the part of the shading material layer corresponding to the micro light-emitting diode, and forming a shading structure covering the isolation column.

As an optional technical solution, forming the space between the isolation layers in S2 further includes:

forming a low surface energy functional layer on the substrate, wherein the low surface energy functional layer covers the micro light-emitting diode array; and

and patterning the low-surface-energy functional layer to form a plurality of grooves, wherein the grooves correspond to the isolation grooves one to one.

As an optional technical solution, the low surface energy functional layer is selected from a silicon dioxide functional layer, a silicon nitride functional layer or an aluminum oxide functional layer.

As an optional technical solution, the S3 further includes:

forming a shading material layer on the substrate and covering the low surface energy functional layer and the isolation columns; and

and heating and curing, wherein the shading material is gathered towards the isolation column to form a shading structure covering the isolation column.

Compared with the prior art, the micro light-emitting diode display panel and the manufacturing method thereof provided by the invention have the advantages that the isolation column with a larger height-width ratio is obtained in advance, and the light shielding structure is formed on the outer side of the isolation column, so that the high and narrow light shielding structure is accurately manufactured, the technical problems of pixel unsharpness, contrast reduction and the like caused by light leakage, reflection and the like of the micro light-emitting diode in the micro light-emitting diode display panel are solved, and the special technical effects of improving the pixel definition, the contrast and the like are further achieved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic cross-sectional view of a micro led display panel according to an embodiment of the invention.

Fig. 2 is a flowchart of a method for manufacturing a micro led display panel according to an embodiment of the invention.

Fig. 3 to 9 are schematic views illustrating a process of manufacturing a micro led display panel according to an embodiment of the invention.

Detailed Description

The present invention will be described in detail below with reference to specific embodiments shown in the drawings. These embodiments are not intended to limit the present invention, and structural, methodological, or functional changes made by those skilled in the art according to these embodiments are included in the scope of the present invention.

As shown in fig. 1, an embodiment of the invention provides a micro led display panel 100, which includes a substrate 10, a micro led array 20 formed on the substrate 10, and an isolation trench 24 between any adjacent micro leds in the micro led array 20; a plurality of isolation pillars 30, each isolation pillar 30 being disposed in a corresponding isolation groove 24; and light shielding structures 40, wherein the light shielding structures 40 are formed on the top surfaces and the side surfaces of the corresponding isolation pillars 30, the top surfaces protrude towards the light emitting surfaces of the micro light emitting diodes, and the side surfaces are arranged around the top surfaces.

In this embodiment, a plurality of isolation pillars 30 are formed on the substrate 10 corresponding to the isolation trenches 24, and then the light-shielding structure 40 is formed on the outer surface of the isolation pillars 30, preferably, the isolation pillars 30 may be made of a non-light-shielding material, so that a structure with a large aspect ratio, i.e., a structure with a large height and a narrow width can be obtained by patterning the isolation layer made of the non-light-shielding material; and the top surface and the side surface of the isolation column are covered with shading structures, and the shading structures cover the isolation column as a whole and can be regarded as high and narrow shading structures. In other words, the high and narrow light shielding structure can be formed by coating the isolation pillar with the light shielding structure, so that the problem that the high and narrow light shielding structure cannot be prepared by directly patterning thicker light shielding photoresist in the conventional micro light emitting display diode panel is solved.

In addition, since the isolation pillars 30 pad up the portions of the light-shielding structures 40 located in the isolation trenches 24, the film thickness of the light-shielding structures 40 formed on the isolation pillars 30 can be reduced, thereby avoiding the problem of incomplete etching of the light-shielding material (or the light-absorbing material) during the patterning process.

As shown in fig. 1, the micro light emitting diode array 20 includes a plurality of pixels, each of which includes at least 3 sub-pixels, i.e., a first sub-pixel 21, a second sub-pixel 22, and a third sub-pixel 23. In this embodiment, the first sub-pixel 21, the second sub-pixel 22 and the third sub-pixel 23 are micro light emitting diodes having blue light, respectively, but not limited thereto. In other embodiments of the present invention, the first sub-pixel, the second sub-pixel, and the third sub-pixel may be a red light micro-led, a green light micro-led, and a blue light micro-led, respectively.

When the first sub-pixel 21, the second sub-pixel 22 and the third sub-pixel 23 are blue micro-leds, a red quantum dot layer 61 and a green quantum dot layer 62 may be disposed on any two sub-pixels, respectively, so that the micro-led display panel 100 can perform a color display.

As shown in fig. 1, the micro led display panel 100 further includes a low surface energy functional layer 50 formed on a surface of the micro led array 20 away from the substrate 10, the low surface energy functional layer 50 having a groove 51 corresponding to the isolation groove 24, or the groove 51 is located in the isolation groove 24. Wherein the isolation pillars 30 protrude from the substrate 10 in the trenches 51.

In this embodiment, the size of the slot 51 is smaller than the size of the isolation slot 24. That is, a part of the low-surface functional layer 50 exists in the separation groove 24, and the purpose thereof is to urge the light shielding structure 40 toward the separation column 30.

Specifically, the surface energy of the isolation pillars 30 is the same or approximately the same as the surface energy of the light shielding structure 40, and both are made of high surface energy materials, so that when the light shielding material with high surface energy is coated on the low surface functional layer 50, the light shielding material is not easily spread on the surface of the low surface functional layer 50, and is gathered toward the isolation pillars 30 with high surface energy, and then the light shielding material gathered on the surface of the isolation pillars 50 is cured to form the light shielding structure 40 through a heating process.

In a preferred embodiment, the low surface energy functional layer 50 is selected from a silicon dioxide functional layer, a silicon nitride functional layer, or an aluminum oxide functional layer.

In other embodiments of the present invention, the light shielding structure formed on the isolation pillar may be obtained through a patterning process. Specifically, a shading photoresist is coated on the substrate to cover the micro light-emitting diode array and the isolation columns, wherein the parts of the shading photoresist corresponding to the micro light-emitting diodes are removed after exposure and development, the parts of the shading photoresist corresponding to the isolation columns are reserved, and the parts of the shading photoresist corresponding to the isolation columns are solidified to form a shading structure.

As shown in fig. 2, the present invention further provides a method 200 for manufacturing a micro led display panel, which includes:

s1, providing a substrate, wherein the surface of one side of the substrate comprises a micro light-emitting diode array, the micro light-emitting diode array comprises a plurality of micro light-emitting diodes, and an isolation groove is arranged between any two micro light-emitting diodes;

s2, forming an isolation layer on the substrate, wherein the isolation layer covers the micro light-emitting diode array, the isolation layer is patterned to form a plurality of isolation columns, and each isolation column is located in a corresponding isolation groove; and

and S3, forming a shading structure on the isolation columns, wherein the shading structure covers the top surfaces and the side surfaces of the isolation columns.

The following describes in detail a process of fabricating the micro led display panel 100 shown in fig. 1 by the method 200 of fabricating the micro led display panel shown in fig. 2 with reference to fig. 3 to 9.

As shown in fig. 3, a substrate 10 is provided, and a surface of one side of the substrate 10 includes a micro light emitting diode array 20, and an isolation groove 24 is formed between any two micro light emitting diodes in the micro light emitting diode array 20.

The substrate 10 is, for example, a TFT substrate, the micro light emitting diode array 20 is, for example, transferred onto the TFT substrate by a bulk transfer method, the micro light emitting diode array 20 forms a plurality of pixels, each pixel at least includes 3 sub-pixels, each of the 3 sub-pixels corresponds to 3 micro light emitting diodes, and an isolation groove 24 is included between any two micro light emitting diodes.

As shown in fig. 4, a low surface energy functional material 52 is formed on the surface of the micro-led array 20 on the side away from the substrate 10. The low surface functional material 52 is selected from silicon dioxide, silicon nitride, or aluminum oxide, and may be formed by chemical vapor deposition.

As shown in fig. 5, patterning the low surface energy functional material 52 forms the trenches 51 and the low surface functional layer 50; wherein, the slot 51 is arranged corresponding to the isolation slot 24, and the size of the slot 51 is slightly smaller than that of the isolation slot 24, so that part of the low surface energy functional layer 50 is located in the isolation slot 24.

As shown in fig. 6 and 7, the isolation layer 31 is coated on the low surface functional layer 50, a photoresist is coated on the isolation layer 31, and then the isolation layer corresponding to the micro light emitting diode is removed by exposure and development to form a plurality of isolation pillars 30, wherein the isolation pillars 30 are located in the isolation trenches 24, and the isolation pillars 30 protrude from the trench 51 to one side of the substrate 10.

The material of the isolation layer 31 is, for example, a high surface energy material. The isolation layer 31 is, for example, a non-light-absorbing organic film layer, including but not limited to polyimide, etc.

As shown in fig. 8 and 9, the light-shielding material layer 41 is applied to the surface of the low surface energy functional layer 50 and the side of the support posts 30 away from the substrate 10, wherein the surface energy of the light-shielding material layer 41 is the same as or similar to the surface energy of the spacer layer 31.

The light-shielding material layer 41 is heat-treated, and the light-shielding material layer 41 is gathered toward the isolation pillars 30 and is solidified on the side surfaces and the top surfaces of the isolation pillars 30, forming the light-shielding structure 40.

In a preferred embodiment, the light-shielding material layer 41 is selected from light-shielding ink, for example.

The micro led display panel 100 can be obtained by forming a red quantum dot layer 61 and a green quantum dot layer 62 on the first sub-pixel 21 and the second sub-pixel 22 of the micro led array 20 of the micro led display panel shown in fig. 9, respectively.

It should be noted that, in other embodiments of the present invention, the micro led display panel 100 may include only the isolation pillars in the isolation trenches and the light shielding structures formed outside the isolation pillars, without including the low surface energy functional layer.

At this time, the corresponding manufacturing method is simplified in that an isolation layer is formed on a substrate with a micro light-emitting diode array, the isolation layer is patterned, a plurality of support columns are formed, and each support column is located in a corresponding isolation groove; then, coating a shading material layer to one side of the micro light-emitting diode array, which is far away from the substrate, wherein the shading material layer covers the micro light-emitting diodes and the support pillars; and continuously patterning the shading material layer, removing the shading material layer corresponding to the micro light-emitting diode, reserving the shading material layer on the outer side of the supporting column, and then solidifying and reserving the shading material layer on the outer side of the supporting column to form a shading structure. The thickness of the film layer of the shading material layer can be obviously smaller than that of the film layer of the support pillar, so that the problem of incomplete etching is not easy to occur in the patterning process.

Because the supporting columns heighten the shading structure positioned in the isolation groove, the technical effect same as that of the existing narrow and high shading layer can be achieved, but the shading structure provided by the invention has the advantage of easiness in preparation.

In summary, according to the micro led display panel and the manufacturing method thereof provided by the present invention, the isolation pillar with a large aspect ratio is obtained in advance, and then the light shielding structure is formed on the outer side of the isolation pillar, so as to accurately manufacture the high and narrow light shielding structure, thereby solving the technical problems of unclear pixels, reduced contrast, and the like caused by light leakage, reflection, and the like of the micro led in the micro led display panel, and further achieving special technical effects of improving the pixel definition, the contrast, and the like.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.