CN114335368A

CN114335368A - Light emitting device, manufacturing method thereof and display device

Info

Publication number: CN114335368A
Application number: CN202111602337.6A
Authority: CN
Inventors: 张晓远; 李广如; 卢志高
Original assignee: BOE Technology Group Co Ltd; Beijing BOE Technology Development Co Ltd
Current assignee: BOE Technology Group Co Ltd; Beijing BOE Technology Development Co Ltd
Priority date: 2021-12-24
Filing date: 2021-12-24
Publication date: 2022-04-12
Anticipated expiration: 2041-12-24

Abstract

The application provides a light-emitting device, a manufacturing method thereof and a display device. Through setting the second electrode layer into a plurality of sub-electrode blocks arranged at intervals, one part of light emitted by the light-emitting functional layer is reflected by the second electrode layer and then is emitted after being reflected for a plurality of times in the optical resonant cavity formed by the second electrode layer and the first electrode layer, the other part of light (in the area not shielded by the second electrode layer) is directly emitted by the light-emitting functional layer, when the visual angle of a person changes, the person eye can receive the light directly emitted without being reflected by the optical resonant cavity, and the components of the part of light cannot change along with the change of the visual angle, so that the phenomenon that the spectrum of the emitted light is red-shifted or blue-shifted can be improved.

Description

Light emitting device, manufacturing method thereof and display device

Technical Field

The application relates to the technical field of display, in particular to a light-emitting device, a manufacturing method thereof and a display device.

Background

Quantum dot light-emitting diodes (QLEDs) have the advantages of active light emission, adjustable emission spectrum, narrow emission wavelength range, and the like, and with the development of the technology, the QLED technology is increasingly and widely applied to display devices. The QLED light-emitting device can be divided into a bottom emission type and a top emission type according to the emergent mode of light, the light-emitting efficiency of the bottom emission type device is limited by the aperture opening ratio of pixels, a light source is difficult to effectively utilize, the OLED light-emitting device needs to operate in a high-brightness state to achieve the required brightness, the light-emitting efficiency is low, the service life is short, the structure of the top emission type device avoids the influence of a substrate bottom layer circuit, the aperture opening ratio is improved, and the light-emitting efficiency and the service life are both improved.

However, the conventional top emission type QLED light emitting device has a problem that a spectrum of emitted light is red-shifted or blue-shifted, which affects a display effect.

Disclosure of Invention

The application provides a light-emitting device, a manufacturing method thereof and a display device aiming at the defects of the prior art, and aims to solve the problem that the spectrum of emitted light of a QLED light-emitting device in the prior art is red-shifted or blue-shifted.

In a first aspect, embodiments of the present application provide a light emitting device, including:

a substrate;

the light-emitting functional layer is arranged on one side of the substrate and comprises a plurality of sub-pixel units arranged at intervals;

a first electrode layer and a second electrode layer provided on opposite sides of the light-emitting functional layer, the first electrode layer and the second electrode layer being configured to apply a voltage to the light-emitting functional layer;

the second electrode layer comprises at least one connecting block and a plurality of sub-electrode blocks arranged at intervals, and orthographic projections of the sub-electrode blocks on the substrate are not overlapped; at least part of the sub-electrode blocks are connected to the same connecting block, and the aperture opening ratio of the second electrode layer in each sub-pixel unit is 5-95%.

Optionally, the first electrode layer is located on a side of the light-emitting functional layer close to the substrate, and the second electrode layer is located on a side of the light-emitting functional layer far from the substrate; alternatively, the first and second electrodes may be,

the first electrode layer is located on one side, far away from the substrate, of the light-emitting functional layer, and the second electrode layer is located on one side, close to the substrate, of the light-emitting functional layer.

Optionally, in the row direction, the distances between the adjacent sub-electrode blocks are equal; and/or the distances between the adjacent sub-electrode blocks are equal in the column direction.

Optionally, the orthographic projection shapes of the plurality of sub-electrode blocks on the substrate are the same.

Optionally, the shape of the sub-electrode block includes a rectangle, a square, a circle, a triangle, a trapezoid or a sector.

Optionally, in the row direction, the widths of the sub-electrode blocks are equal; and/or the widths of the sub-electrode blocks are equal in the column direction.

Optionally, in the row direction, the width of the sub-electrode block is greater than or equal to 1 micrometer and less than or equal to 1 millimeter; and/or in the column direction, the width of the sub-electrode block is greater than or equal to 1 micrometer and less than or equal to 1 millimeter.

Optionally, an auxiliary contact layer is disposed between the second electrode layer and the light-emitting functional layer, and the auxiliary contact layer is connected to the second electrode layer and the light-emitting functional layer respectively;

an orthographic projection of the auxiliary contact layer on the substrate overlaps with an orthographic projection of the second electrode layer on the substrate, and an orthographic projection of the auxiliary contact layer on the substrate overlaps with an orthographic projection of the light-emitting functional layer on the substrate.

Optionally, the light transmittance of the auxiliary contact layer is greater than or equal to 85%.

Optionally, in a direction from the substrate to the second electrode layer, the light-emitting functional layer includes an electron transport layer, a quantum dot layer, an interface dipole layer, a hole transport layer, and a hole injection layer, which are sequentially stacked; or the light-emitting function layer comprises a hole injection layer, a hole transport layer, a quantum dot layer and an electron transport layer which are sequentially stacked.

Optionally, in a direction in which the substrate points to the light emitting functional layer, the thickness of the second electrode layer is greater than or equal to 10 nanometers and less than or equal to 25 nanometers.

In a second aspect, embodiments of the present application provide a display apparatus including a light emitting device in embodiments of the present application.

In a third aspect, an embodiment of the present application provides a method for manufacturing a light emitting device, including:

providing a substrate;

manufacturing a light-emitting functional layer, a first electrode layer and a second electrode layer on one side of the substrate, wherein the light-emitting functional layer comprises a plurality of sub-pixel units which are arranged at intervals, the first electrode layer and the second electrode layer are arranged on the opposite sides of the light-emitting functional layer and are used for applying voltage to the light-emitting functional layer, the second electrode layer comprises at least one connecting block and a plurality of sub-electrode blocks which are arranged at intervals, and orthographic projections of the sub-electrode blocks on the substrate are not overlapped; at least part of the sub-electrode blocks are connected to the same connecting block, and the aperture opening ratio of the second electrode layer in each sub-pixel unit is 5-95%.

Optionally, the manufacturing a light emitting functional layer, a first electrode layer, and a second electrode layer on one side of the substrate includes:

sequentially manufacturing a first electrode layer and a light-emitting functional layer on one side of the substrate, and manufacturing a second electrode layer on one side, far away from the substrate, of the light-emitting functional layer through a composition process; alternatively, the first and second electrodes may be,

and manufacturing a second electrode layer on one side of the substrate through a composition process, and sequentially manufacturing a light-emitting functional layer and a first electrode layer on one side of the second electrode layer far away from the substrate.

Optionally, the method further includes: and manufacturing an auxiliary contact layer between the light-emitting functional layer and the second electrode layer, wherein the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the second electrode layer on the substrate, and the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the light-emitting functional layer on the substrate.

The beneficial technical effects brought by the technical scheme provided by the embodiment of the application comprise:

the light-emitting device in the embodiment of the application comprises a light-emitting functional layer, a first electrode layer and a second electrode layer, wherein the first electrode layer and the second electrode layer are arranged on different sides of the light-emitting functional layer; at least part of the sub-electrode blocks are connected to the same connecting block, and the opening ratio of the second electrode layer in each sub-pixel unit is 5-95%. Through setting the second electrode layer into a plurality of sub-electrode blocks arranged at intervals, one part of light emitted by the light-emitting functional layer is reflected by the second electrode layer and then is emitted after being reflected for a plurality of times in the optical resonant cavity formed by the second electrode layer and the first electrode layer, the other part of light (in the area not shielded by the second electrode layer) is directly emitted by the light-emitting functional layer, when the visual angle of a person changes, the person eye can receive the light directly emitted without being reflected by the optical resonant cavity, and the components of the part of light cannot change along with the change of the visual angle, so that the phenomenon that the spectrum of the emitted light is red-shifted or blue-shifted can be improved.

Additional aspects and advantages of the present application will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the present application.

Drawings

The foregoing and/or additional aspects and advantages of the present application will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic structural view of a light emitting device in the prior art;

fig. 2 is a schematic structural diagram of a light emitting device provided in an embodiment of the present application;

fig. 3 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

fig. 4 is a schematic structural diagram of another light-emitting device provided in an embodiment of the present application;

fig. 5a to 5c are schematic top views of different shapes of the second electrode layer at the sub-pixel units in the embodiment of the present application;

FIG. 6 is a schematic view of an optical path of a light emitting device in an embodiment of the present application;

fig. 7a to 7h are schematic top views of second electrode layers with different shapes in the embodiment of the present application;

fig. 8 is a schematic diagram illustrating materials and energy levels of various layers of a light emitting device according to an embodiment of the present disclosure;

fig. 9 is a schematic diagram of materials and energy levels of various film layers of another light-emitting device provided by an embodiment of the present application;

fig. 10 is a schematic view illustrating a manufacturing process of a light emitting device according to an embodiment of the present disclosure;

fig. 11a to 11i are schematic structural diagrams of different processes for manufacturing a light emitting device according to an embodiment of the present disclosure;

fig. 12a to 12k are schematic structural diagrams of another different process for manufacturing a light emitting device according to an embodiment of the present application.

In the figure:

10-a light emitting device; 11-a substrate; 110-thin film transistors; 12-a light-emitting functional layer; 120-sub-pixel cells; 111-pixel banks;

13-a first electrode layer; 14-a second electrode layer; 140-a sub-electrode block; 141-connecting block; 142-a connecting line;

15-auxiliary contact layer; 16-protective layer and light extraction layer;

121-hole injection layer; 122-a hole transport layer; 123-quantum dot layer; 124-electron transport layer; a 125-interfacial dipole layer;

23-a fully reflective layer; 24-transflective layer.

Detailed Description

Reference will now be made in detail to the present application, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the same or similar parts or parts having the same or similar functions throughout. In addition, if a detailed description of the known art is not necessary for illustrating the features of the present application, it is omitted. The embodiments described below with reference to the drawings are exemplary only for the purpose of explaining the present application and are not to be construed as limiting the present application.

It will be understood by those within the art that, unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. 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 prior art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

As used herein, the singular forms "a", "an", "the" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and/or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it can be directly connected or coupled to the other element or intervening elements may also be present. Further, "connected" or "coupled" as used herein may include wirelessly connected or wirelessly coupled. As used herein, the term "and/or" includes all or any element and all combinations of one or more of the associated listed items.

Referring to fig. 1, the inventor of the present application considers that, for an Organic-Light-emitting diode (OLED) Light emitting device or a QLED Light emitting device, when the Light emitting function layer is located between the total reflection layer 23 and the semi-transparent semi-reflection layer 24, the Light emitting function layer 12, the total reflection layer 23 and the semi-transparent semi-reflection layer 24 form an optical resonant cavity. Due to the reflection effect of the total reflection layer 23 and the semi-transparent and semi-reflective layer 24 on light, light emitted by the light emitting functional layer 12 can be reflected for multiple times in the optical resonant cavity and then emitted from the semi-transparent and semi-reflective layer 24, and the front emission of light with specific wavelength can be enhanced by adjusting the length of the cavity, so that the light emitting efficiency is improved, and the enhancement effect of the optical resonant cavity on the emergent light is called as a microcavity effect. However, when the human viewing angle changes, the light component of the emergent light received by the human eye changes (for example, red light is increased and blue light is decreased, or red light is decreased and blue light is increased), that is, the spectrum of the emergent light is red-shifted or blue-shifted.

The application provides a light-emitting device, a manufacturing method thereof and a display device, and aims to solve the technical problems in the prior art.

The following describes a light emitting device, a method for manufacturing the same, and a display device in detail with reference to the accompanying drawings.

As shown in fig. 2, 3, 4, and 5a, the light emitting device 10 in the embodiment of the present application includes:

a substrate 11;

a light emitting function layer 12 disposed on one side of the substrate 11 and including a plurality of sub-pixel units 120 disposed at intervals;

a first electrode layer 13 and a second electrode layer 14 provided on opposite sides of the light-emitting function layer 12, the first electrode layer 13 and the second electrode layer 14 being for applying a voltage to the light-emitting function layer 12;

the second electrode layer 14 includes at least one connection block 141 and a plurality of sub-electrode blocks 140 arranged at intervals, and orthographic projections of the sub-electrode blocks 140 on the substrate 11 are not overlapped; at least some of the sub-electrode blocks 140 are connected to the same connection block 141, and the aperture ratio of the second electrode layer 14 is 5% to 95% in each sub-pixel unit 120.

Specifically, a plurality of thin film transistors 110 and a driver circuit (not shown) are provided over the substrate 11. The first electrode layer 13 and the second electrode layer 14 are disposed on opposite sides of the light emitting function layer 12, and the first electrode layer 13 and the second electrode layer 14 are used to apply a voltage to the light emitting function layer 12 to cause the light emitting function layer 12 to emit light. The material of the first electrode layer 13 includes metal or metal oxide, and the transmittance and the reflectance of the first electrode layer 13 are relatively low and high by adjusting the thickness or the composition of the material, even if the first electrode layer 13 is an opaque film layer. The material of the second electrode layer 14 includes a metal or a metal oxide, and specifically includes one of metal materials such as silver, aluminum, magnesium, lead, germanium, indium, gallium, nickel, titanium, chromium, and the like, or one or more of metal oxides such as indium zinc oxide, indium gallium zinc oxide, zinc tin oxide, and the like. By adjusting the thickness or the composition of the material of the second electrode layer 14, the reflectance and the light transmittance of the second electrode layer 14 are balanced even if the second electrode layer 14 is a semi-reflective and semi-transparent film layer. The thickness of the second electrode layer 14 (the thickness in the direction perpendicular to the substrate 11) may be 10 nm to 25 nm, and may be adjusted according to the actual situation.

In an embodiment of the present application, as shown in fig. 2 to 5a, the light emitting device 10 includes a plurality of pixel banks 111, and the plurality of pixel banks 111 divide the light emitting function layer 12 into a plurality of sub-pixel units 120 arranged at intervals. It should be noted that the plurality of sub-electrode blocks 140 in the second electrode layer 14 may correspond to the plurality of sub-pixel units 120 one to one, that is, each sub-pixel unit 120 may correspond to one sub-electrode block 140, or may correspond to a plurality of sub-electrode blocks 140. Optionally, as shown in fig. 2 and fig. 5a, in the plurality of sub-pixel units 120, each sub-pixel unit 120 corresponds to a plurality of sub-electrode blocks 140, so that a plurality of regions on each sub-pixel unit 120, which are shielded by the sub-electrode blocks 140, and a plurality of regions which are not shielded by the sub-electrode blocks 140 are arranged at intervals, which is beneficial to making the light emission of the sub-pixel units 120 more uniform, and improving the light emission effect of the light emitting device 10.

The aperture ratio of the second electrode layer 14 is 5% to 95% at the position corresponding to each sub-pixel unit 120, that is, the area of the sub-electrode block 140 is greater than or equal to 5% and less than or equal to 95% of the area of the sub-pixel unit 120 at the position corresponding to each sub-pixel unit 120. The ratio of the area of the sub-electrode block 140 to the area of the sub-pixel unit 120 affects the light emitting effect of the light emitting device 10. The larger the ratio of the area of the sub-electrode block 140 to the area of the sub-pixel unit 120 is, the more the sub-electrode block 140 shields the sub-pixel unit 120, the more the part of the light emitted by the sub-pixel unit 120 after being reflected for multiple times is, that is, the more the part is strengthened by the optical resonator, and the phenomenon that the spectrum of the corresponding emergent light is more likely to generate red shift or blue shift is obtained. The smaller the ratio of the area of the sub-electrode block 140 to the area of the sub-pixel unit 120, the less the sub-electrode block 140 blocks the sub-pixel unit 120, and the more the light emitted by the sub-pixel unit 120 is emitted without being reflected by the second electrode layer 14. Therefore, by controlling the ratio of the area of the sub-electrode block 140 to the area of the sub-pixel unit 120 within a suitable range, a balance between enhancing the front emission of light with a specific wavelength and improving the red shift or blue shift of the emitted light can be achieved, i.e., the advantages and disadvantages of the microcavity effect can be balanced.

Further, at the position corresponding to each sub-pixel unit 120, the area of the sub-electrode block 140 is made to be greater than or equal to 7% of the area of the sub-pixel unit 120 and less than or equal to 60% of the area of the sub-pixel unit 120. Therefore, the emergent light with specific wavelength can be enhanced, and the red shift or blue shift of the spectrum of the emergent light caused by the microcavity effect can be improved.

Referring to fig. 2 and 5a, in the manufacturing process of the light emitting device 10, the second electrode layer 14 may be patterned to form a plurality of discontinuous independent patterns, that is, the second electrode layer 14 includes a plurality of sub-electrode blocks 140 disposed at intervals. At least some of the sub-electrode blocks 140 of the plurality of sub-electrode blocks 140 are connected to the same connection block 141 by the connection lines 142 and then connected to the driving circuit (not shown in fig. 5 a), so that the plurality of sub-electrode blocks 140 connected to each other can receive the same electrical signal, so that the voltages on the plurality of sub-electrode blocks 140 connected to each other are the same.

As shown in fig. 2 and fig. 6, the second electrode layer 14 is provided as a plurality of sub-electrode blocks 140 disposed at intervals, a part of light emitted by the light-emitting functional layer 12 is reflected by the second electrode layer 14, and then is reflected for a plurality of times in the optical resonant cavity formed by the second electrode layer 14 and the first electrode layer 13, and the other part of light (in the region not shielded by the second electrode layer 14) is directly emitted by the light-emitting functional layer 12, when the viewing angle of a person changes, the person's eye can receive the light directly emitted without being reflected by the optical resonant cavity, and the component of the part of light does not change with the change of the viewing angle, so that the phenomenon that the spectrum of the emitted light is red-shifted or blue-shifted can be improved. On the other hand, although the optical resonance formed by the first electrode layer 13 and the second electrode layer 14 is strong to enhance the front emission of light with a specific wavelength, the second electrode layer 14 also absorbs light to a certain extent, and the second electrode layer 14 weakens the emission of light to a certain extent, and by arranging the second electrode layer 14 into a plurality of sub-electrode blocks 140 arranged at intervals, part of light emitted by the light-emitting function layer 12 can be directly emitted, so that the weakening effect of the second electrode layer 14 on the emitted light is improved, and the light-emitting efficiency of the light-emitting device 10 is further improved.

As shown in fig. 2 and 3, when the first electrode layer 13 is located on the side of the light-emitting functional layer 12 close to the substrate 11 and the second electrode layer 14 is located on the side of the light-emitting functional layer 12 far from the substrate 11, light emitted from the light-emitting functional layer 12 is emitted through the top of the substrate 11, and the light-emitting device 10 is a top-emission type device. The positions of the first electrode layer 13 and the second electrode layer 14 may also be interchanged, as shown in fig. 4, the first electrode layer 13 is located on the side of the light-emitting functional layer 12 away from the substrate 11, the second electrode layer 14 is located on the side of the light-emitting functional layer 12 close to the substrate 11, light emitted by the light-emitting functional layer 12 is emitted through the bottom of the substrate 11, and the light-emitting device 10 is a bottom-emission type device. Specific positions of the first electrode layer 13 and the second electrode layer 14 may be adjusted according to actual conditions, and are not limited herein, and specifically, the first electrode layer 13 may be an anode, the second electrode layer 14 may be a cathode, the first electrode layer 13 may also be a cathode, and the second electrode layer 14 may also be an anode.

In the embodiment of the present application, the distance between the sub-electrode blocks 140 may be adjusted according to actual conditions, and optionally, in the row direction (i.e., the horizontal direction), the distances between adjacent sub-electrode blocks 140 are equal; and/or, the spacing between the adjacent sub-electrode blocks 140 is equal in the column direction (i.e., vertical direction). That is, in the row arrangement direction of the sub-pixel units 120, the sub-electrode blocks 140 are uniformly distributed, and the distances between two adjacent sub-electrode blocks 140 are equal; or in the column arrangement direction of the sub-pixel units 120, the sub-electrode blocks 140 are uniformly distributed, and the distances between two adjacent sub-electrode blocks 140 are equal; or in the row direction and the column direction, the plurality of sub-electrode blocks 140 are uniformly arranged, and the distances between two adjacent sub-electrode blocks 140 are equal. Therefore, when the second electrode layer 14 is patterned to form the plurality of sub-electrode blocks 140, the process is easier and the light emission of the light emitting device 10 is more uniform.

As shown in fig. 7a to 7g, the shape of the sub-electrode block 140 may be rectangular, square, circular, triangular, trapezoidal, fan-shaped, circular arc-shaped, etc., and the shapes of the plurality of sub-electrode blocks 140 may be the same or different. Optionally, the orthographic projection shapes of the sub-electrode blocks 140 on the substrate 11 are the same, so that the manufacturing process of the second electrode layer 14 can be simplified, and the light emission of the light-emitting device 10 is more uniform. The size of the sub-electrode block 140 can be adjusted according to actual conditions, and if the size of the sub-pixel unit 120 is larger, the size of the sub-electrode block 140 is correspondingly larger. As shown in fig. 5b and 7g, each sub-pixel unit 120 corresponds to one sub-electrode block 140. When the sub-pixel unit 120 has a size of 106 micrometers by 317.5 micrometers (317.5 micrometers long and 106 micrometers wide), the sub-electrode blocks may be arranged in a square shape of 50 micrometers by 50 micrometers, the sub-electrode blocks 140 corresponding to different sub-pixel units 120 may be connected to an external driving circuit through connection lines having a width of 2 micrometers, and the aperture ratio of the second electrode layer 14 is about 7.4%. As shown in fig. 5c and 7h, each sub-pixel unit 120 corresponds to one sub-electrode block 140. When the sub-pixel unit 120 has a size of 106 micrometers by 317.5 micrometers (317.5 micrometers long and 106 micrometers wide), the sub-electrode block may be configured as a rectangle with a size of 100 micrometers by 200 micrometers, and the aperture ratio of the second electrode layer 14 is about 59.4%.

As shown in fig. 2 and 5a, alternatively, the widths W of the sub-electrode blocks 140 are equal in the row direction; and/or, the widths W of the sub-electrode blocks 140 are equal in the column direction, so that the manufacturing process of the second electrode layer 14 can be simplified, and the uniformity of the light emitted from the light emitting device 10 can be improved. In the row direction, the width W of the sub-electrode block 140 is greater than or equal to 1 μm and less than or equal to 1 mm; and/or, in the column direction, the width W of the sub-electrode block 140 is greater than or equal to 1 micrometer and less than or equal to 1 millimeter. The specific size of the sub-electrode block 140 can be adjusted according to actual conditions, but it is necessary to ensure that the ratio of the area of the sub-electrode block 140 to the area of the sub-pixel power supply is within a reasonable range, so as to achieve a balance between enhancing the front emission of light with specific wavelength and improving the red shift or blue shift of the emitted light.

As shown in fig. 2, optionally, in an embodiment of the present application, an auxiliary contact layer 15 is disposed between the second electrode layer 14 and the light-emitting functional layer 12, the auxiliary contact layer 15 is electrically connected to the second electrode layer 14 and the light-emitting functional layer 12, an orthogonal projection of the auxiliary contact layer 15 on the substrate 11 overlaps an orthogonal projection of the second electrode layer 14 on the substrate 11, and an orthogonal projection of the auxiliary contact layer 15 on the substrate 11 overlaps an orthogonal projection of the light-emitting functional layer 12 on the substrate 11. The auxiliary contact layer is made of a material with a relatively low resistivity, so that good ohmic contact is formed between the auxiliary contact layer and the second electrode layer 14 and between the auxiliary contact layer and the light-emitting functional layer. By providing the auxiliary contact layer 15 between the second electrode layer 14 and the light-emitting functional layer 12, current non-uniformity caused by discrete contact between the second electrode layer 14 and the light-emitting functional layer 12 due to patterning of the second electrode layer 14 can be improved, and the light-emitting effect of the light-emitting device 10 is ensured. The material of the auxiliary contact layer 15 includes one or more of gallium, gallium phosphide, gallium arsenide, graphene, lanthanum nickelate, indium tin oxide, indium oxide, tin oxide, aluminum zinc oxide, and indium yttrium oxide, which can be determined according to the actual situation. The light transmittance of the auxiliary contact layer 15 may be changed by adjusting the thickness of the auxiliary contact layer 15 and the material composition. Optionally, the light transmittance of the auxiliary contact layer 15 is greater than or equal to 85%, so that the absorption of the auxiliary contact layer 15 on the light emitted by the light-emitting functional layer 12 can be reduced, and the light-emitting effect of the light-emitting device 10 is ensured.

The specific structure of the light-emitting functional layer 12 may be determined according to actual circumstances. As shown in fig. 2, in a specific embodiment of the present application, the light emitting function layer 12 includes a hole injection layer 121, a hole transport layer 122, a quantum dot layer 123, and an electron transport layer 124, which are sequentially stacked in a direction (a first direction in fig. 2) toward the second electrode layer 14 along the substrate 11, and materials and energy levels of the respective layers may be as shown in fig. 8. As shown in fig. 3, in another specific embodiment of the present application, the light-emitting functional layer 12 includes an electron transport layer 124, a quantum dot layer 123, an interfacial dipole layer 125, a hole transport layer 122, and a hole injection layer 121, which are sequentially stacked in a direction (first direction in fig. 3) toward the second electrode layer 14 along the substrate 11, and the materials and energy levels of the respective layers may be as shown in fig. 9. When the hole transport layer 122 is disposed on the quantum dot layer 123 in the light-emitting functional layer 12 (the quantum dot layer 123 is fabricated first and then the hole transport layer 122 is fabricated on the quantum dot layer 123 in the fabrication of the light-emitting functional layer 12), the interface dipole layer 125 is disposed between the quantum dot layer 123 and the hole transport layer 122, so as to change the hydrophilic and hydrophobic properties of the surface of the quantum dot layer 123 and prevent the quantum dot layer 123 from being damaged by the material solvent of the hole transport layer 122 in the subsequent fabrication of the hole transport layer 122. The material of the interfacial dipole layer 125 includes an organic material such as polyethyleneimine.

Based on the same inventive concept, the present embodiment also provides a display apparatus including the light emitting device 10 provided in the present embodiment. Since the display apparatus includes the light emitting device 10 provided in the embodiments of the present application, the display apparatus has the same advantageous effects as the light emitting device 10, and thus, the detailed description thereof is omitted.

Based on the same inventive concept, the present embodiment further provides a method for manufacturing a light emitting device 10, as shown in fig. 10, including:

s101, providing a substrate;

s102, manufacturing a light-emitting functional layer, a first electrode layer and a second electrode layer on one side of a substrate, wherein the light-emitting functional layer comprises a plurality of sub-pixel units arranged at intervals, the first electrode layer and the second electrode layer are arranged on the opposite sides of the light-emitting functional layer and used for applying voltage to the light-emitting functional layer, the second electrode layer comprises at least one connecting block and a plurality of sub-electrode blocks arranged at intervals, and orthographic projections of the sub-electrode blocks on the substrate are not overlapped; at least part of the sub-electrode blocks are connected to the same connecting block, and the opening ratio of the second electrode layer in each sub-pixel unit is 5-95%.

In the manufacturing method of the embodiment of the application, the second electrode layer 14 is manufactured into the plurality of sub-electrode blocks 140 arranged at intervals, a part of light emitted by the light-emitting functional layer 12 is reflected by the second electrode layer 14, and then is emitted after being reflected for multiple times in the optical resonant cavity formed by the second electrode layer 14 and the first electrode layer 13, and another part of light (in the area not shielded by the second electrode layer 14) is directly emitted by the light-emitting functional layer 12.

In a specific embodiment, the fabrication of the light emitting functional layer 12, the first electrode layer 13 and the second electrode layer 14 on one side of the substrate 11 in the embodiment of the present application includes:

sequentially manufacturing a first electrode layer 13 and a light-emitting functional layer on one side of a substrate, and manufacturing a second electrode layer on one side, far away from the substrate, of the light-emitting functional layer through a composition process; alternatively, the first and second electrodes may be,

and manufacturing a second electrode layer on one side of the substrate through a patterning process, and sequentially manufacturing a light-emitting functional layer and a first electrode layer on one side of the second electrode layer, which is far away from the substrate 11.

In another specific embodiment, the manufacturing method of the present application further includes: and manufacturing an auxiliary contact layer between the light-emitting functional layer and the second electrode layer, wherein the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the second electrode layer on the substrate, and the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the light-emitting functional layer on the substrate.

The following describes in detail a specific process of fabricating the light emitting device 10 according to the first embodiment with reference to the drawings.

Specifically, the patterning process in the embodiment of the present application includes a part or all of processes of coating, exposing, developing, etching, and removing the photoresist.

As shown in fig. 11a, first, a substrate 11 is provided. The substrate 11 includes a thin film transistor 110 and an associated driving circuit (not shown in the figure) disposed on the substrate 11. The substrate 11 is then cleaned with water, ethanol, and acetone, and the cleaned substrate 11 is treated with ultraviolet ozone for 10 minutes to remove impurities on the surface of the substrate 11.

As shown in fig. 11b, next, a first electrode layer 13 is formed on one side of the substrate 11, and the first electrode layer 13 may be a three-layer composite structure composed of ITO, silver, and ITO, where silver plays a role of reflecting light and ITO plays a role of conducting electricity. The first electrode layer 13 can be formed by physical vapor deposition.

As shown in fig. 11c, a plurality of pixel banks 111 are formed on one side of substrate 11 at intervals by a patterning process, and a region between two adjacent pixel banks 111 is a region where sub-pixel unit 120 is formed, that is, a pixel pit.

As shown in fig. 11d, a solution of ethyl sulfide containing cuprous thiocyanate is then spin-coated at 3000 rpm on the side of the first electrode layer 13 away from the substrate 11, followed by annealing at 135 ℃ for 20 minutes, and then the substrate 11 is transferred to a glove box and the annealing is continued for 5 minutes to form a hole injection layer 121 of cuprous thiocyanate. The material and the manufacturing process parameters of the hole injection layer 121 may be adjusted according to practical situations, and are not limited herein.

As shown in fig. 11e, a polytriphenylamine solution with a concentration of 8 mg/ml is then spin-coated on the side of the hole injection layer 121 facing away from the substrate 11 and annealed at 135 c for 20 minutes to form a hole transport layer 122. The material and fabrication process parameters of the hole transport layer 122 can be adjusted according to practical situations.

As shown in fig. 11f, a 10 mg/ml quantum dot solution is then spin-coated on the side of the hole transport layer 122 away from the substrate 11, followed by annealing at 120 ℃ for 10 minutes to form a quantum dot layer 123. The content of the quantum dot solution, the spin coating parameters of the quantum dot solution and the annealing parameters can be adjusted according to actual conditions.

As shown in fig. 11g, a solution of zinc oxide nanoparticles of 30 mg/ml is then spin-coated on the side of the quantum dot layer 123 away from the substrate 11, followed by annealing at 120 ℃ for 10 minutes to form the electron transport layer 124. The material of the electron transport layer 124 and the spin coating parameters of the solution and the related parameters of the annealing process can be adjusted according to the actual situation.

As shown in fig. 11h, transparent graphene of about 2 nm is then deposited by chemical vapor deposition on the side of the quantum dot layer 123 away from the substrate 11 to form the auxiliary contact layer 15.

As shown in fig. 11i, the second electrode layer 14 is then formed on the side of the auxiliary contact layer 15 away from the substrate 11, specifically, the substrate 11 is transferred to a vacuum evaporator to evaporate a layer of aluminum, and then the aluminum layer is patterned to form the second electrode layer 14 including a plurality of sub-electrode blocks 140, so as to complete the fabrication of the light emitting device 10. The material of the second electrode layer 14 can be adjusted according to practical situations, and is not limited herein. Finally, the light emitting device 10 is packaged.

The following describes in detail a specific process of fabricating the light emitting device 10 according to the second embodiment with reference to the drawings.

As shown in fig. 12a, first, a substrate 11 is provided. The substrate 11 includes a thin film transistor 110 and an associated driving circuit (not shown in the figure) disposed on the substrate 11. The substrate 11 is then rinsed with water, ethanol, and acetone, and the substrate 11 is treated with ultraviolet ozone for 10 minutes to remove impurities from the surface of the substrate 11.

As shown in fig. 12b, next, a first electrode layer 13 is formed on one side of the substrate 11, and the first electrode layer 13 may be a three-layer composite structure of ITO, silver, and ITO, where silver plays a role of reflecting light and ITO plays a role of conducting electricity. The first electrode layer 13 can be formed by physical vapor deposition.

As shown in fig. 12c, a plurality of pixel banks 111 are formed on one side of substrate 11 at intervals by a patterning process, and a region between two adjacent pixel banks 111 is a region where sub-pixel unit 120 is formed, that is, a pixel pit.

As shown in fig. 12d, a solution of zinc oxide nanoparticles of 30 mg/ml is spin-coated on the side of the first electrode layer 13 away from the substrate 11, and then annealed at 120 ℃ for 10 minutes to form an electron transport layer 124. The material of the electron transport layer 124 and the spin coating parameters of the solution and the related parameters of the annealing process can be adjusted according to the actual situation.

As shown in fig. 12e, a 10 mg/ml quantum dot solution is spin-coated on the side of the electron transport layer 124 away from the substrate 11, and then annealed at 120 ℃ for 10 minutes to form a quantum dot layer 123. The content of the quantum dot solution, the spin coating parameters of the quantum dot solution and the annealing parameters can be adjusted according to actual conditions.

As shown in fig. 12f, a solution of ethylene glycol monomethyl ether containing polyethyleneimine is then deposited on the side of quantum dot layer 123 remote from substrate 11, with the polyethyleneimine content of 5%, followed by annealing at 120 ℃ for 10 minutes to form an interfacial dipole layer 125. The interface dipole layer 125 can change the hydrophilic and hydrophobic properties of the quantum dot surface, and prevent the quantum dot layer 123 from being damaged by the material solvent of the hole transport layer 122 when the hole transport layer is manufactured subsequently.

As shown in fig. 12g, a solution of polyvinylcarbazole in chlorobenzene, the content of polyvinylcarbazole in the chlorobenzene solution being 8 mg per ml, is then deposited on the side of the interfacial dipole layer 125 remote from the substrate 11. Followed by annealing at 135 c for 20 minutes to form the hole transport layer 122.

As shown in fig. 12h, an ethanol solution containing nickel oxide is then deposited on the side of the hole transport layer 122 away from the substrate 11, the content of nickel oxide in the ethanol solution being 15 mg/ml, and then annealed at 120 ℃ for 10 minutes, to form the hole injection layer 121.

As shown in fig. 12i, lanthanum nickelate is then deposited on the side of the hole injection layer 121 remote from the substrate 11 to form the auxiliary contact layer 15.

As shown in fig. 12j, next, a second electrode layer 14 is formed on the side of the auxiliary contact layer 15 away from the substrate 11 by a patterning process. Specifically, a metal layer is formed through an evaporation process and then patterned to form the second electrode layer 14 including the plurality of sub-electrode blocks 140. The material of the second electrode layer 14 includes magnesium, aluminum or silver, and the specific material and thickness thereof can be adjusted according to actual conditions.

Next, as shown in fig. 12k, 70nm of NPB (a diamine derivative) was deposited as a protective layer and a light extraction layer 16 on the side of the second electrode layer 14 away from the substrate 11 to complete the fabrication of the light-emitting device 10. The protective layer and the light extraction layer 16 can prevent the second electrode layer 14 from being oxidized after being in contact with air. After that, the light emitting device 10 is packaged.

In both of the two specific manufacturing methods provided in the embodiments of the present application, the first electrode layer 13, the light-emitting function layer 12, and the second electrode layer 14 are sequentially stacked on the substrate 11, that is, the first electrode layer 13, the light-emitting function layer 12, and the second electrode layer 14 are sequentially manufactured. The second electrode layer 14, the light emitting function, and the first electrode layer 13 may also be sequentially stacked on the substrate 11, that is, the second electrode layer 14, the light emitting function layer 12, and the first electrode layer 13 are sequentially fabricated on the substrate 11, and the specific fabrication process may refer to the case of sequentially fabricating the first electrode layer 13, the light emitting function, and the second electrode layer 14, which is not described herein again.

By applying the embodiment of the application, at least the following beneficial effects can be realized:

1. the light emitting device 10 in the embodiment of the present application includes a light emitting function layer 12, and a first electrode layer 13 and a second electrode layer 14 disposed on opposite sides of the light emitting function layer 12, wherein the second electrode layer 14 includes at least one connection block 141 and a plurality of sub-electrode blocks 140 disposed at intervals, and orthographic projections of the sub-electrode blocks 140 on a substrate 11 are not overlapped; at least some of the sub-electrode blocks 140 are connected to the same connection block 141, and the aperture ratio of the second electrode layer 14 is 5% to 95% in each sub-pixel unit 120. By arranging the second electrode layer 14 into a plurality of sub-electrode blocks 140 arranged at intervals, a part of light emitted by the light-emitting functional layer 12 is reflected by the second electrode layer 14, and then is emitted after being reflected for a plurality of times in an optical resonant cavity formed by the second electrode layer 14 and the first electrode layer 13, and another part of light (in an area not shielded by the second electrode layer 14) is directly emitted by the light-emitting functional layer 12.

2. In the embodiment of the present application, by making the intervals between the adjacent sub-electrode blocks 140 equal in the row direction; and/or, the distances between the adjacent sub-electrode blocks 140 are made equal in the column direction, and when the second electrode layer 14 is patterned to form a plurality of sub-electrode blocks 140, the process is easier, and the light emission of the light emitting device 10 is more uniform.

3. In the embodiment of the present application, by making the width of the sub-electrode block 140 greater than or equal to 1 μm and less than or equal to 1 mm in the row direction; and/or, making the width of the sub-electrode block 140 greater than or equal to 1 micron and less than or equal to 1 millimeter in the column direction, the ratio of the area of the sub-electrode block 140 to the area of the sub-pixel power supply can be made within a reasonable range to achieve a balance between enhancing the front emission of light of a specific wavelength and improving the red shift or blue shift of the emitted light.

4. By providing the auxiliary contact layer 15 between the second electrode layer 14 and the light-emitting functional layer 12, current non-uniformity caused by discrete contact between the second electrode layer 14 and the light-emitting functional layer 12 due to patterning of the second electrode layer 14 can be improved, and the light-emitting effect of the light-emitting device 10 is ensured.

5. When the hole transport layer 122 is disposed on the quantum dot layer 123 in the light-emitting functional layer 12 (the quantum dot layer 123 is fabricated first and then the hole transport layer 122 is fabricated on the quantum dot layer 123 in the fabrication of the light-emitting functional layer 12), the interface dipole layer 125 is disposed between the quantum dot layer 123 and the hole transport layer 122, so as to change the hydrophilic and hydrophobic properties of the surface of the quantum dot layer 123 and prevent the quantum dot layer 123 from being damaged by the material solvent of the hole transport layer 122 in the subsequent fabrication of the hole transport layer 122.

In the description of the present application, it is to be understood that the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", and the like indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience in describing the present application and simplifying the description, but do not indicate or imply that the referred device or element must have a particular orientation, be constructed in a particular orientation, and be operated, and thus should not be construed as limiting the present application.

The terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present application, "a plurality" means two or more unless otherwise specified.

In the description herein, particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The foregoing is only a partial embodiment of the present application, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present application, and these modifications and decorations should also be regarded as the protection scope of the present application.

Claims

1. A light emitting device, comprising:

a substrate;

2. The light-emitting device according to claim 1, wherein the first electrode layer is located on a side of the light-emitting function layer close to the substrate, and the second electrode layer is located on a side of the light-emitting function layer away from the substrate; alternatively, the first and second electrodes may be,

3. The light-emitting device according to claim 2, wherein the sub-electrode blocks are equally spaced in the row direction; and/or the distances between the adjacent sub-electrode blocks are equal in the column direction.

4. The light-emitting device according to claim 2, wherein orthographic shapes of the plurality of sub-electrode blocks on the substrate are the same.

5. A light emitting device as claimed in claim 2, wherein the shape of the sub-electrode block includes a rectangle, a square, a circle, a triangle, a trapezoid or a sector.

6. The light-emitting device according to claim 2, wherein the widths of the sub-electrode blocks in the row direction are equal; and/or the widths of the sub-electrode blocks are equal in the column direction.

7. The light-emitting device according to claim 6, wherein the sub-electrode block has a width of 1 μm or more and 1 mm or less in a row direction; and/or in the column direction, the width of the sub-electrode block is greater than or equal to 1 micrometer and less than or equal to 1 millimeter.

8. The light-emitting device according to claim 1, wherein an auxiliary contact layer is provided between the second electrode layer and the light-emitting functional layer, and the auxiliary contact layer is connected to the second electrode layer and the light-emitting functional layer, respectively;

9. The light-emitting device according to claim 8, wherein a light transmittance of the auxiliary contact layer is greater than or equal to 85%.

10. The light-emitting device according to any one of claims 1 to 9, wherein the light-emitting function layer comprises an electron transport layer, a quantum dot layer, an interfacial dipole layer, a hole transport layer, and a hole injection layer, which are sequentially stacked in a direction from the substrate to the second electrode layer; or the light-emitting function layer comprises a hole injection layer, a hole transport layer, a quantum dot layer and an electron transport layer which are sequentially stacked.

11. The light-emitting device according to any one of claims 1 to 9, wherein a thickness of the second electrode layer is greater than or equal to 10 nm and less than or equal to 25 nm in a direction in which the substrate is directed to the light-emitting function layer.

12. A display device characterized by comprising the light-emitting device according to any one of claims 1 to 10.

13. A method of fabricating a light emitting device, comprising:

providing a substrate;

14. The method according to claim 13, wherein the step of forming a light-emitting functional layer, a first electrode layer, and a second electrode layer on one side of the substrate comprises:

15. The method of manufacturing according to claim 14, further comprising: and manufacturing an auxiliary contact layer between the light-emitting functional layer and the second electrode layer, wherein the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the second electrode layer on the substrate, and the orthographic projection of the auxiliary contact layer on the substrate is overlapped with the orthographic projection of the light-emitting functional layer on the substrate.