CN103187533B - A kind of organic electroluminescence device and preparation method thereof - Google Patents

Abstract

The present invention relates to an organic electroluminescent device and a preparation method thereof. The organic electroluminescent device comprises the following layers stacked in sequence: a substrate, a first electrode layer, an organic functional layer, and a second electrode layer, and it also includes a A low refractive index grid layer, the refractive index of the grid layer is greater than 1.0 and lower than the refractive index of the organic functional layer, the grid layer is placed between the first electrode layer and the organic functional layer, or The grid layer is placed between the substrate and the first electrode layer. Through the adjustment of the optical path of the light beam by the grid layer, part of the light beam originally lost due to total reflection enters the glass and reaches the air, thereby improving the brightness and efficiency of the organic light-emitting display device.

Description

A kind of organic electroluminescence device and preparation method thereof

technical field

The present invention relates to an organic light emitting device (Organic Light Emitting Device, also referred to as OLED hereinafter), in particular to an organic light emitting device including a grid layer. The invention also relates to a method for preparing the organic electroluminescent device.

Background technique

OLED has a multi-layer structure, including substrate, anode layer, organic functional layer and cathode layer. The substrate is usually made of a material with a refractive index less than 1.7 (for example, the refractive index of a glass substrate is generally 1.4-1.5) and the organic functional layer thereon generally has a refractive index of 1.7-1.8. Therefore, a large part of the light beam is totally reflected at the interface between the organic functional layer with a higher refractive index and the substrate with a lower refractive index and is confined in the organic functional layer, cannot enter the substrate and reaches the air, so that Only about 20% of the light actually emitted by OLEDs into the air, and about 80% of the light is confined or lost inside the device and cannot be taken out for applications. In order to obtain high-brightness and high-efficiency OLEDs, the light output efficiency of OLEDs must be greatly improved.

In US20040119402, it is introduced that the substrate is made into a trapezoidal shape and a groove is made on the trapezoidal shape, and an OLED device is made in it, so that the beam confined in the organic layer and emitted to the side of the device passes through the trapezoidal shaped substrate to reach the front surface of the substrate, Therefore, the efficiency and brightness of the device are improved. However, this method only takes out the light beam at the edge of the device, and the substrate of this structure has a complicated shape, making it difficult to manufacture and high in manufacturing cost.

CN1498046A introduces adding a layer of light scattering layer between the glass substrate and the first electrode layer, so that the light beam confined in the organic layer due to total reflection between the organic layer and the glass substrate interface changes the optical path through scattering, so that part of the light beam Enter the glass substrate and reach the air, improving the efficiency and brightness of the device. However, this method also makes the light beam that can originally enter the glass substrate confined in the organic layer due to scattering and changing the optical path. This method has a low overall improvement in device efficiency or brightness. At the same time, due to the complicated preparation process of the scattering layer, the actual application value is not good. high.

CN1571595B describes adding a light loss prevention layer and a micro-gap layer inside an OLED device. Wherein, the optical loss prevention layer is composed of a plurality of diffraction gratings with protrusions; the micro-gap layer is composed of gas or vacuum filling. However, due to the high fineness requirements of the diffraction grating, the manufacturing process is complicated and the yield is low. Moreover, filling the device with gas will cause problems such as product stability, unsatisfactory durability, and poor product consistency.

Contents of the invention

An object of the present invention is to provide an organic light emitting display device having improved light output performance and being easy to manufacture.

The organic light-emitting display device of the present invention includes the following layers stacked in sequence: a substrate, a first electrode layer, an organic functional layer, and a second electrode layer, and it also includes a low-refractive index grid layer, and the grid layer The refractive index is greater than 1.0 and lower than the refractive index of the organic functional layer, the grid layer is located between the first electrode layer and the organic functional layer, or the grid layer is located between the substrate and the first electrode layer .

The present invention also provides a method for preparing the organic light-emitting display device, comprising forming the low-refractive-index grid layer on a substrate, and then sequentially depositing a first electrode layer, an organic functional layer, and a second electrode layer stacked on each other; or Depositing a first electrode layer on the substrate, forming a low-refractive index grid layer on the first electrode layer, and then sequentially depositing an organic functional layer and a second electrode layer stacked on each other; and then encapsulating.

The organic light-emitting display device of the present invention includes the low-refractive index grid layer, so that a part of the light beam originally lost at the interface between the organic functional layer and the substrate due to total reflection can be adjusted by the low-refractive index grid layer to the optical path of the light beam. Instead, it is injected into the substrate to reach the air. Therefore, the organic light emitting display device of the present invention has improved brightness and efficiency. Moreover, since the low-refractive-index grid layer does not require high processing fineness, it can be produced by a simple process such as photolithography, and the product consistency is good.

Description of drawings

1 is a cross-sectional view of the structure (comparative example 1) of an organic light-emitting display device in the prior art;

Fig. 2 is a graphic diagram of light-emitting pixels in Comparative Example 1;

Fig. 3 is the square grid layer pattern of embodiment 1;

Fig. 4 is the square grid pattern shown in the pixel area of embodiment 1;

5 is a cross-sectional view of an OLED structure of the present invention;

6 is a cross-sectional view of another OLED structure of the present invention;

FIG. 7 is a square nested grid pattern displayed in the pixel area;

FIG. 8 is a hexagonal nested grid pattern displayed in the pixel area;

FIG. 9 is a circular nested grid pattern displayed in the pixel area;

Figure 10 is a hexagonal grid pattern arranged in a close adjacent manner in a single pixel area;

FIG. 11 is a grid pattern of hexagons arranged in close proximity shown in the pixel area.

detailed description

The organic light-emitting display device of the present invention includes the following layers stacked in sequence: a substrate, a first electrode layer, an organic functional layer, and a second electrode layer, and it also includes a low-refractive index grid layer, and the grid layer The refractive index is greater than 1.0 and lower than the refractive index of the organic functional layer, the grid layer is located between the first electrode layer and the organic functional layer, or the grid layer is located between the substrate and the first electrode layer .

The grid layer can be made of any material that has the refractive index and is suitable for OLEDs. In order to facilitate the formation of grid patterns thereon, it is preferable to use photoresist to prepare the grid layer, such as photosensitive for touch panels. Insulation and protective layer photoresist EOC130.

In order to allow more light to enter the substrate and reach the air, preferably the grid layer is located between the substrate and the first electrode layer.

The refractive index of the grid layer is preferably 1.0-1.5. The lower the refractive index of the grid layer is, the more light beams enter the substrate and reach the air, and the greater the brightness of the display device is improved.

In order to allow more light that adjusts the light path through the grid layer to enter the substrate and into the air, the light transmittance of the grid layer is preferably 75%-99%.

For the convenience of manufacture, the grid layer preferably has a thickness of 0.1 μm to 20 μm, more preferably 0.1 μm to 5 μm.

In each pixel area, the pattern formed by the convex part of the grid layer is preferably: a plurality of regular N-gons of the same size arranged in a close adjacent manner (that is, each regular N side not located at the outermost shape share each side with other adjacent regular N-gons), so that the grid layer pattern is net-like, and each side of the regular N-gon is a convex part; or a series of concentric shapes nested layer by layer A plurality of regular N-gons or circles that are the same but of different sizes, wherein the ratio of the area of the area outside the largest regular N-gon or circle within the boundary of each pixel area to the total area of the pixel area is preferably greater than 0 and not higher than 1/4. Where N≥3, and the regular N-gon is preferably a regular triangle, square or regular hexagon.

The width of each side of the above-mentioned regular N-gons arranged in a closely adjacent manner, or the width d1 of each convex part in each largest regular N-gon or circle in the above-mentioned layer-by-layer nesting pattern is preferably 0.05 μm～ 20 μm, the radius of the circumscribed circle of each regular N-gon gap in the above-mentioned closely adjacent regular N-gon grid, or each gap in each largest regular N-gon or circle in the nested pattern The width d2 (excluding the centralmost void) is preferably 1 μm to 30 μm, and the width of the centralmost void is preferably less than twice the width d2 of other voids in the largest regular N-gon or circle. The size of d1 and d2 affects the brightness of the device. In order to improve the brightness of the device, d1 is more preferably 0.05 μm to 5 μm, especially 0.05 μm to 3 μm, and d2 is more preferably 1 μm to 10 μm.

The area of the grid layer other than the pixel area may have a grid pattern, or may not have a grid pattern, and may be used as a raised portion.

The OLED may be composed of an insulating layer and a spacer layer to define a pixel area, and the insulating layer and the spacer layer are stacked on each other and located between the grid layer and the organic functional layer or between the first electrode layer and the organic functional layer. However, when the grid layer does not have a grid pattern in a portion other than the pixel area, the OLED may not additionally include the insulating layer. The insulating layer and the spacer layer can be made by using materials and methods conventionally used in the art for making the insulating layer and the spacer layer, for example, photoresist is used to make it by photolithography.

In the OLED, a transparent first electrode layer and a reflective second electrode layer may be used, or a reflective first electrode layer and a transparent second electrode layer may be used, or a transparent first electrode layer may be used. and a transparent second electrode layer.

In the embodiments herein, either one of the first electrode layer and the second electrode layer can be an anode, and the other can be a cathode, and can be prepared using materials conventionally used to manufacture electrode layers, such as ITO (Indium Tin Oxide) or Ag or Al.

The organic functional layer generally includes a hole transport layer, a light-emitting layer and an electron transport layer, all of which can be prepared using materials commonly used in the prior art to manufacture these layers. As the material of the hole transport layer, for example, aromatic amine materials, low molecular materials, etc., such as N,N'-di-(1-naphthyl)-N,N'-diphenyl-1,1'-bi Phenyl-4,4'-diamine (NPB); as the material of the electron transport layer, for example, metal-organic complexes, aromatic condensed rings or o-phenanthrolines, etc., such as tris(8-hydroxyquinoline) can be used Aluminum (Alq ₃ ). The light-emitting layer can be composed of materials commonly used in light-emitting layers in the art, for example, it can be composed of a light-emitting layer host material and a light-emitting layer dye. The host material of the light-emitting layer can be a material conventionally used for this purpose in the art, such as small molecule materials such as metal-organic complexes, carbazole derivatives, anthracene derivatives, etc., such as 9,10-di(naphthalene-2-yl) Anthracene (ADN). The light-emitting layer dye can be a material conventionally used for this purpose in the art, for example, a compound or a perylene derivative containing at least one atom with an atomic number greater than 36 and less than 84, such as 2,5,8,11-tetra-tert-butylperylene (TBPe). The ratio of the host material of the light-emitting layer and the dye of the light-emitting layer can use its conventional ratio in the art.

In addition, the organic functional layer may further include a hole injection layer and/or an electron injection layer, and both the hole injection layer and the electron injection layer may use materials commonly used in the prior art for the hole injection layer or the electron injection layer. The material of the hole injection layer can be, for example, m-MTDATA, and the material of the electron injection layer can be, for example, LiF.

The thicknesses of the above-mentioned layers can adopt their conventional thicknesses in OLEDs.

Fig. 5 shows a cross-sectional view of an OLED structure of the present invention. Wherein, 10 is a substrate; 20 is a first electrode layer; 30 is a low refractive index grid layer; 40 is an organic functional layer, which may include a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer; 50 is a second electrode layer. electrode layer.

Fig. 6 shows a cross-sectional view of another device structure of the present invention. Wherein, 10 is a substrate; 30 is a grid layer; 20 is a first electrode layer; 40 is an organic functional layer, which may include a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer; 50 is a second electrode layer.

The preparation of the organic light-emitting display device of the present invention includes forming the low-refractive-index grid layer on the substrate, and then sequentially depositing the first electrode layer, the organic functional layer and the second electrode layer stacked on each other; or depositing the first electrode layer on the substrate. An electrode layer, forming a low-refractive index grid layer on the first electrode layer, and then sequentially depositing an organic functional layer and a second electrode layer stacked on each other; and then encapsulating.

The grid layer can be prepared, for example, by photolithography, or by any other suitable method known to those skilled in the art. When the grid layer is prepared by photolithography, the preparation process mainly includes: coating a photoresist with the refractive index on the substrate or on the first electrode layer; drying; using a mask with a desired pattern exposing the mold; and developing.

The deposition can be any suitable method known to those skilled in the art that can cover the entire target surface with the substances required by the method of the present invention, such as vacuum evaporation. Encapsulation may be by any suitable method known to those skilled in the art.

The present invention will be further described by the following examples. The brightness is measured with a silicon photodiode. In various embodiments, the low index grid layer is formed to have the same refractive index as the material used to form it.

Comparative example 1

Using ITO conductive glass as the substrate, etch the ITO first electrode pattern, in which the thickness of ITO is 200nm, and prepare the insulating layer and isolation column layer with a thickness of 1-3μm by photolithography, so that the pixel size is 0.28mm×0.28mm. The ITO conductive glass substrate is put into an evaporation chamber, and the chamber pressure is lower than 5.0×10 ^-3 Pa during the evaporation process. First, 40nm thick N,N'-bis-(1-naphthyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine (NPB) was evaporated as hole transport Layer; 30nm thick 9,10-bis(naphthalene-2-yl)anthracene (ADN) and 2,5,8,11-tetra-tert-butylperylene (TBPe) were evaporated as the light-emitting layer by double-source co-evaporation , the ratio of TBPe in ADN was controlled by rate to be 7%; 20nm tris(8-hydroxyquinoline)aluminum (Alq ₃ ) was vapor-deposited as electron transport layer; 0.5nm LiF was vapor-deposited as electron injection layer and 150nm Al as the second electrode layer.

FIG. 1 is a cross-sectional view of the device structure of Comparative Example 1. Among them, 10 is the substrate; 20 is the first electrode layer ITO; 40 is the organic functional layer, including the hole transport layer, light emitting layer, electron transport layer, electron injection layer; 50 is the second electrode layer.

FIG. 2 is a graphic diagram of light-emitting pixels in Comparative Example 1. FIG.

Example 1:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: Spin-coat a layer of transparent photoresist on the ITO pattern (photosensitive insulation and protective layer photoresist EOC130 for touch panels, light transmittance greater than 80%, and refractive index 1.5). After drying, select the mask of continuous inverse square grid pattern to expose with the exposure amount of 150mj/cm ² ; Obtain specific figure (square grid, square grid, d1 is as defined above and is 1 μm, d2 is as defined above and is 8 μm) grid layer. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Fig. 3 is the grid layer pattern of embodiment 1;

Fig. 4 is the grid pattern shown in the pixel area of embodiment 1;

Example 2:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of anti-square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 0.05 μm, d2 is a grid layer of 1 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 3:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of anti-square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (similar square grid with embodiment 1, but d1 is 1 μm, d2 is a grid layer of 4 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 4:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is the grid layer of 2μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 5:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (similar square grid with embodiment 1, d1 is 8 μm after developing with the method identical with embodiment 1) , d2 is the grid layer of 25 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Embodiment 6:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO layer is prepared, the ITO anode is etched by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode.

Embodiment 7:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of anti-square nested pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern after developing with the method identical with embodiment 1 (in each pixel region, a series of concentric A grid of multiple squares nested layer by layer, where the largest square in each pixel area is the same size as the pixel area, d1 is 1 μm, and d2 is 4 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

FIG. 7 is a square nested grid pattern in the pixel area of Embodiment 7. FIG.

Embodiment 8:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of inverse square nested pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar pattern with embodiment 7, d1 is 1 μm, d2 is the grid layer of 4 μm). On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO first electrode layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Embodiment 9:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of anti-hexagonal nested pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern after developing with the method identical with embodiment 1 (in each pixel region, a series of concentric In the form of multiple hexagonal grids nested layer by layer, the distance between the two parallel sides of the largest hexagon in each pixel area is equal to the side length of the pixel area, d1 is 1 μm, and d2 is 4 μm) grid layer. On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO first electrode layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

FIG. 8 is a hexagonal nested grid pattern in the pixel area of Embodiment 9. FIG.

Example 10:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of anti-circular nested pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern after developing with the method identical with embodiment 1 (in each pixel region, a series of concentric The form is a grid of multiple circles nested layer by layer, where the largest circle in each pixel area is inscribed in the pixel area, d1 is 1 μm, and d2 is 4 μm). On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO first electrode layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

FIG. 9 is a circular nested grid pattern in the pixel area of the tenth embodiment.

Example 11:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid layer is as follows: spin-coat a layer of transparent photoresist (transmittance greater than 80%, refractive index 1.3) on the ITO pattern. After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 12:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid layer is as follows: a layer of transparent photoresist (transmittance greater than 80% and refractive index 1.3) is spin-coated on the substrate. After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO first electrode layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 13:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid layer is as follows: spin-coat a layer of transparent photoresist (transmittance greater than 80%, refractive index 1.7) on the ITO pattern. After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Example 14:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid layer is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of continuous inverse hexagonal grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (regular hexagonal grid, d1 is 1 μ m) after developing with the method identical with embodiment 1 , d2 is a grid layer of 5 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially, and the pressure of the chamber during the evaporation process is lower than 5.0×10 ^-3 Pa. In this embodiment, the organic layer is first vapor-deposited with a thickness of 40 nm NPB as the hole transport layer; ADN and TBPe with a thickness of 30 nm are vapor-deposited as the light-emitting layer by a double-source co-evaporation method, and the ratio of TBPe in ADN is controlled to be 7% through the rate. ; Evaporation of 20nm of Alq ₃ as the electron transport layer; evaporation of 0.5nm of LiF as the electron injection layer and 150nm of Al as the second electrode layer.

FIG. 10 is a hexagonal grid pattern in a single pixel area of Embodiment 14. FIG.

FIG. 11 is a hexagonal grid pattern of the pixel area of the fourteenth embodiment.

Example 15:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of the reverse hexagonal grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (regular hexagonal grid similar to embodiment 14) after developing with the method identical with embodiment 1 , d1 is 1 μm, d2 is 5 μm) grid layer. On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is evaporated as electron transport layer; 0.5nm LiF is evaporated as electron injection layer and 150nm Al is evaporated as second electrode layer.

Comparative example 2:

The transparent glass is used as the substrate, and a layer of 100 nm silver is fabricated on it by sputtering or vapor deposition as the first electrode. After the silver first electrode pattern was etched, an insulating layer and spacer column layer were prepared on it in the same manner as in Comparative Example 1, so that the pixel size was 0.28mm×0.28mm. Putting it into an evaporation chamber to evaporate a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a second electrode layer in sequence. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is vapor-deposited as the electron transport layer; 0.5nm Li is vapor-deposited as the electron injection layer, and 150nm ITO is made by sputtering method as the second electrode layer.

Example 16:

Using transparent glass as a substrate, a layer of 100nm silver is fabricated by sputtering or vapor deposition as the first electrode. After etching the pattern of the silver first electrode, prepare a layer of low-refractive-index grid layer on it with a thickness of about 2 μm. The preparation process of the low-refractive-index grid layer is as follows: spin-coat a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) on the silver pattern. After drying, select the mask of the reverse hexagonal grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (regular hexagonal grid similar to embodiment 14) after developing with the method identical with embodiment 1 , d1 is 1 μm, d2 is 5 μm) grid layer. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is vapor-deposited as the electron transport layer; 0.5nm Li is vapor-deposited as the electron injection layer, and 150nm ITO is made by sputtering method as the second electrode layer.

Example 17:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) on the substrate. After drying, select the mask of the reverse hexagonal grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific figure (regular hexagonal grid similar to embodiment 14) after developing with the method identical with embodiment 1 , d1 is 1 μm, d2 is 5 μm) grid layer. Afterwards, a layer of 100 nm silver is fabricated as the first electrode by sputtering or vapor deposition. After etching the silver first electrode pattern. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Putting it into an evaporation chamber to evaporate a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a second electrode layer in sequence. The chamber pressure is lower than 5.0×10 ^-3 Pa during the evaporation process. In this embodiment, the organic layer is first vapor-deposited with a thickness of 40 nm NPB as the hole transport layer; ADN and TBPe with a thickness of 30 nm are vapor-deposited as the light-emitting layer by a double-source co-evaporation method, and the ratio of TBPe in ADN is controlled to be 7% through the rate. ; Evaporate 20nm of Alq ₃ as the electron transport layer; evaporate 0.5nm of Li as the electron injection layer, and then use the sputtering method to make 150nm of ITO as the second electrode layer.

Comparative example 3:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode, an insulating layer and spacer layer were prepared on it in the same manner as in Comparative Example 1, so that the pixel size was 0.28mm×0.28mm. Putting it into an evaporation chamber to evaporate a hole transport layer, a light-emitting layer, an electron transport layer, an electron injection layer, and a second electrode layer in sequence. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is vapor-deposited as the electron transport layer; 0.5nm Li is vapor-deposited as the electron injection layer, and 150nm ITO is made by sputtering method as the second electrode layer.

Example 18:

Using the same ITO conductive glass as in Comparative Example 1 as the substrate, after etching the ITO first electrode pattern, a low refractive index grid layer was prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive-index grid is as follows: spin-coat a layer of transparent photoresist on the ITO pattern (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5). After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^{- 3} Pa. First, 40nm-thick NPB was evaporated as the hole transport layer; 30nm-thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is vapor-deposited as the electron transport layer; 0.5nm Li is vapor-deposited as the electron injection layer, and 150nm ITO is made by sputtering method as the second electrode layer.

Example 19:

A transparent glass is used as a substrate, and a low-refractive-index grid layer is prepared on it, with a thickness of about 2 μm. The preparation process of the low-refractive index grid layer is as follows: a layer of transparent photoresist (the same photoresist as in Example 1, with a light transmittance greater than 80% and a refractive index of 1.5) is spin-coated on the substrate. After drying, select the mask of inverse square grid pattern to expose with the exposure of 150mj/cm ² ; Obtain specific pattern (similar square grid with embodiment 1, d1 is 1 μ m after developing with the method identical with embodiment 1) , d2 is a grid layer of 4 μm). On the grid layer, a 150nm ITO first electrode layer was prepared by DC magnetron sputtering. The ITO target material was indium tin alloy, and its composition ratio In:Sn=90%:10%. During the preparation process, the oxygen partial pressure was 0.4 Sccm, and the argon partial pressure was 20 Sccm. After the ITO layer is prepared, the ITO first electrode is etched out by an etching method. An insulating layer and a spacer layer were prepared thereon in the same manner as in Comparative Example 1, so that the pixel size was 0.28 mm×0.28 mm. Then put it into the evaporation chamber to evaporate the hole transport layer, the light emitting layer, the electron transport layer, the electron injection layer, and the second electrode layer sequentially. During the evaporation process, the chamber pressure was lower than 5.0×10 ^-3 Pa. First, 40nm thick NPB was evaporated as the hole transport layer; 30nm thick ADN and TBPe were evaporated as the light-emitting layer by dual-source co-evaporation method. The proportion of TBPe in ADN is 7%; 20nm Alq ₃ is vapor-deposited as the electron transport layer; 0.5nm Li is vapor-deposited as the electron injection layer, and 150nm ITO is made by sputtering method as the second electrode layer.

Table 1

Note: The luminance of the transparent device of Comparative Example 3, Example 18, and Example 19 is the luminance of the substrate surface of the device.

As can be seen from the above data, by adding the low-refractive index grid layer of the present invention, the brightness of the device is significantly improved compared with the device without the grid layer, indicating that the use of the low-refractive index grid layer has indeed increased the brightness originally limited in the device. of light output. The OLED in which the grid layer is placed on the substrate has higher brightness than the OLED in which the grid layer is placed on the first electrode layer. Moreover, when the refractive index of the grid layer is lower, the brightness of the device is higher, which indicates that more light confined in the device can be output to the air by using a grid with a lower refractive index. In addition, the above embodiments also show that d1 and d2 of the grid pattern also have a significant impact on the brightness of the device.

Claims (11)

1. An organic electroluminescent device, comprising the following layers laminated in sequence: substrate, first electrode layer, organic functional layer, second electrode layer, and it also includes one layer of low refractive index grid layer, said The refractive index of the grid layer is greater than 1.0 and lower than the refractive index of the organic functional layer, the grid layer is located between the substrate and the first electrode layer, And in each pixel area, the pattern formed by the convex part of the grid layer is: a series of concentrically nested multiple regular N-gons or circles with the same shape and different sizes, wherein Within the boundary of each pixel area, the ratio of the area outside the largest regular N-gon or circle to the total area of the pixel area is greater than 0 and not higher than 1/4; where N≥3; the grid layer The width d1 of each raised part in each largest regular N-gon or circle in the pattern formed by raised parts is 0.05 μm to 20 μm, and each gap in each largest regular N-gon or circle—excluding the center The gap—the width d2 is 1 μm to 30 μm. 2. The organic electroluminescent device according to claim 1, characterized in that the refractive index of the grid layer is 1.0-1.5. 3. The organic electroluminescence device according to claim 1, characterized in that the light transmittance of the grid layer is 75%-99%. 4 . The organic electroluminescence device according to claim 1 , wherein the grid layer has a thickness of 0.1 μm˜20 μm. 5 . The organic electroluminescent device according to claim 1 , wherein the grid layer has a thickness of 0.1 μm˜5 μm. 6 . The organic electroluminescent device according to claim 1 , wherein the regular N-gon is a regular triangle, a square or a regular hexagon. 7. The organic electroluminescent device according to claim 1, characterized in that, the width of the centermost gap in each largest regular N-gon or circle is smaller than the width of other spaces in the largest regular N-gon or circle. Twice the width d2 of each gap. 8 . The organic electroluminescence device according to claim 7 , wherein d1 is 0.05 μm to 5 μm, and d2 is 1 μm to 10 μm. 9. The organic electroluminescent device according to claim 8, characterized in that d1 is 0.05 μm to 3 μm. 10. The organic electroluminescent device according to claim 1, wherein the device adopts a transparent first electrode layer and a second electrode layer with reflective function, or adopts a first electrode layer with reflective function and a second electrode layer with reflective function. A transparent second electrode layer, or a transparent first electrode layer and a transparent second electrode layer. 11. A method for preparing an organic light-emitting display device, characterized in that it comprises forming a low-refractive-index grid layer with a refractive index greater than 1.0 and lower than that of the organic functional layer on a substrate, and making the low-refractive-index grid layer The following pattern: the pattern formed by its raised part is a series of concentrically nested multiple regular N-gons or circles with the same shape but different sizes, where within the boundary of each pixel area, the maximum regular The ratio of the area of the area other than the N-gon or circle to the total area of the pixel area is greater than 0 and not higher than 1/4, where N≥3, and each largest regular N-gon or in the pattern formed by the raised part The width d1 of each convex part in the circle is 0.05 μm to 20 μm, and the width d2 of each void in each largest regular N-gon or circle—excluding the most central void—is 1 μm to 30 μm; and then deposited in sequence The first electrode layer, the organic functional layer and the second electrode layer stacked on each other; and then encapsulation.