CN1472994A - A kind of organic electroluminescence device and preparation method thereof - Google Patents

Abstract

The invention relates to an organic electroluminescent device and a preparation method thereof, belonging to the technical field of electronic semiconductor components. Prepare double-layer isolation columns on the first electrode (2) pattern of the device, the cross-section of the second layer (8) of the isolation column has a shape with a large top and a small bottom, and its hypotenuse has two gradually inward angles α, β, and α>β. Then the organic functional layer (5) and the second electrode (6) are deposited in sequence. Because the existence of the hypotenuse β angle of the second layer (8) of the spacer makes the evaporation angle and the tolerance of the evaporation thickness of the metal back electrode greatly increased, and by using different evaporation angles of the organic functional layer and the metal back electrode, The back electrode can fully cover the organic functional layer, avoiding the exposure of the edge of the organic functional layer, which is more susceptible to water and oxygen corrosion than the metal layer, from the back electrode, thereby improving the life of the device and the uniformity of light emission. The double-layer isolation column is prepared by coating an organic insulating film twice, exposing twice, developing from top to bottom, and curing at a high temperature at the same time. The process is simple, the equipment investment and production costs are low, and the yield is high.

Description

A kind of organic electroluminescence device and preparation method thereof

technical field

The invention relates to an organic electroluminescence device and a preparation method of the device, belonging to the technical field of electronic semiconductor components.

Background technique

Organic Electroluminescent Devices (Organic Electroluminescent Devices, hereinafter referred to as OLEDs) are generally composed of a transparent first electrode on a transparent substrate, an organic electroluminescent medium (organic functional layer) deposited on the first electrode, and an The second electrode (metal electrode) above the organic electroluminescence medium. The transparent electrode serves as the anode of the device, and the metal electrode serves as the cathode of the device. Apply a high level to the transparent electrode and a low level to the metal electrode to make the device emit light. A group of anodes (or cathodes) parallel to each other and a group of cathodes (or anodes) parallel to each other perpendicular thereto form an X-Y two-dimensional addressing matrix.

Usually the pattern wiring of the transparent electrode is realized by photolithography. The pattern wiring of the metal electrodes is realized by metal mask evaporation method or photolithography method. However, in the pattern wiring of the metal electrodes, the manufacturing process of the metal mask is complicated, the cost is high, and the lines are not easy to make thin, so it is difficult to realize high resolution of the device. At the same time, the contact between the metal mask and the organic film will easily damage the organic functional layer, resulting in a short circuit between the transparent electrode and the metal electrode. If the metal wiring is carried out by photolithography, there will be the following problems:

① The baking temperature of the photoresist (such as 120°C) will damage the organic film;

② Solvents, developers, and corrosive solutions of photoresist will damage the organic film;

③ If dry etching is used, the particle flow in it will damage the organic film.

All of the above destructive factors will degrade the performance of the device.

European patent EP0732868B1 (announcement date: May 24, 2000) adopts single-layer spacer column technology for pattern wiring of metal electrodes. The structure of the device is shown in Figure 1: a transparent conductive film 2 is deposited on a transparent substrate 1, and a group of parallel arrays are formed by photolithography of the transparent conductive film 2. A photoresist is spin-coated (hereinafter referred to as spin-coating) on the transparent conductive film 2 , and a plurality of parallel straight lines perpendicular to the transparent conductive film 2 are photoetched from the photoresist. Then through a certain process, the cross section of the straight line forms an inverted trapezoidal shape with a large top and a small bottom (if it is a positive photoresist, the pattern will form an inverted trapezoidal shape by soaking in a C ₆ H ₅ Cl solution; if it is a negative Type photoresist, baked after exposure, that is, the middle baking process makes the pattern form an inverted trapezoid shape), and this straight line with an inverted trapezoidal cross section is the single-layer isolation column (cathode partition wall) 4 of the device. Continue to deposit the organic functional layer 5 and the metal layer 6 on the substrate with the single-layer isolation column 4, due to the shadow effect, no continuous metal film is formed on the side surface of the isolation column, ensuring the electrical connection between adjacent pixels Insulating, metal layer 6 is effectively separated. But this solution has the following disadvantages:

(1) The isolation column 4 is made of a layer of insulating material, and the cross section of the 4 has an inverted trapezoidal shape with a large top and a small bottom.

After depositing the organic functional layer 5 and the metal layer 6, part of the metal layer 6 may fall over the organic layer 5

Into the transparent conductive film 2 between the bottom of the single-layer spacer column 4 and the organic layer 5 (as shown in Figure 2), making

Make the pixel short-circuit and not emit light;

(2) The single-layer spacer column 4 can only be distributed parallel to the direction perpendicular to the transparent electrode 2, and separates the metal electrode 6

At the same time, the reverse suppression voltage between the metal lines is reduced, but the voltage between the first transparent electrodes cannot be reduced.

The reverse suppression voltage between makes the power consumption of the device higher;

(3) Incorporating black dye into the material of the isolation column can improve the contrast of the device when it emits light, due to the single-layer isolation

Columns 4 can only be distributed parallel to the direction perpendicular to the transparent electrode 2, but cannot be parallel to the direction of the transparent electrode 2

The parallel directions are distributed in parallel, so the contrast of the device cannot be significantly improved.

U.S. patent application US20020008467A1 (publication date: January 24, 2002) adopts a kind of double-layer spacer technology to carry out pattern wiring of metal electrodes for the above-mentioned problem that single-layer spacer exists, as shown in Figure 3, this double-layer spacer It consists of two parts: an insulating base 3 with a mesh structure and a positive trapezoidal cross section and a cathode partition wall 4 with an inverted trapezoidal cross section. The preparation process of the spacer column is as follows: First, a layer of photoresist is coated on the transparent substrate prepared with the first electrode and pre-baked. The photoresist can be positive novolac photoresist, negative cyclized rubber, chemically amplified type resin, preferably a positive novolac photoresist; the first layer of photoresist is exposed and developed into a mesh pattern; the first layer of photoresist is baked so that it is not affected by the preparation process of the second layer of photoresist; Coating the second layer of negative photoresist and pre-baking; through exposure, intermediate baking and development, the line cross-section forms an inverted trapezoidal cathode partition pattern; high-temperature baking completely cures the isolation columns, and removes moisture and solvents. But this scheme still has the following disadvantages:

① Form the pattern of the insulating base 3 first, and then form the pattern of the cathode partition 4 on the upper layer in the same way.

Complicated, with many processes, and the surface of the first electrode in the light-emitting area of the device is polluted by two layers of photoresist successively,

It is not conducive to the improvement of the overall performance and yield of the device;

②The cross-section of the cathode partition wall 4 is an inverted trapezoidal shape with a large top and a small bottom. Due to the limitation of the inclination angle of the inverted trapezoid,

Only by vertically evaporating the organic functional layer and obliquely evaporating the metal layer can the metal layer completely cover the edge of the organic functional layer

edge, but the evaporation angle of the organic functional layer is about 70° to make the organic thin film have better uniformity.

This shape of the cross-section of the pole partition wall 4 cannot guarantee the evaporation uniformity of the organic functional layer and the completeness of the metal layer at the same time.

For the purpose of coating the edge of the organic functional layer, it can be said that the isolation effect of the cathode partition wall 4 is poor and not good enough.

change.

Contents of the invention

The object of the present invention is to provide an organic electroluminescent device, thereby effectively dividing the second electrode and improving the performance of the device.

Another object of the present invention is to provide a method for preparing an organic electroluminescent device, which can improve the disadvantages of complex process, low yield and high cost in the previous preparation process of spacers.

In order to achieve the above object, a technical solution of the present invention is to provide an organic electroluminescent device, which consists of a group of first electrodes parallel to each other and a group of second electrodes perpendicular to the first electrodes parallel to each other to form an X-Y two-dimensional homing device. address matrix, the device has a plurality of pixels, each pixel includes a first electrode and a second electrode and an organic functional layer sandwiched between the two electrodes, and a set of The first electrode patterns are parallel to each other and separated with insulating double-layer isolation columns. The first layer of the isolation columns is a network structure or a strip structure, and the cross-section of the lines has a shape of small upper part and larger bottom part. , the line of the second layer of the isolation column is on the line of the first layer of the isolation column and the position is centered. It is characterized in that: the cross section of the line of the second layer of the isolation column is a shape with a large top and a small bottom, and its hypotenuse has two progressive inner The closed angles α, β, and α>β.

The above technical solution is also characterized in that the α angle is 45°-80°, and the β angle is 20°-60°.

The above technical solution is also characterized in that the materials of the first layer and the second layer of the isolation columns are both photosensitive organic insulating materials, and the second layer of organic insulating materials is uniform during coating, exposure, and development. The material that does not affect the photosensitivity and uniformity of the first layer of organic insulating material; the material of the first layer of the isolation column is generally photosensitive polyimide (polyimide, hereinafter referred to as PI), positive novolac photolithography One of rubber, negative cyclized rubber, and chemically amplified photoresist, which is preferably photosensitive PI; the material of the second layer of the isolation column is generally such that the cross section of the line after photolithography can form a large upper and a smaller One of the inverted trapezoidal photoresists is preferably a negative photoresist.

The hypotenuse of the cross-section of the second layer of the double-layer spacer column in the organic electroluminescent device provided by the present invention has two angles α and β that are gradually retracted, because the existence of the β angle makes the evaporation angle of the metal back electrode and The tolerance of the evaporation thickness is greatly increased, and by using different evaporation angles between the organic functional layer and the metal back electrode, the back electrode can completely cover the organic functional layer, avoiding being more susceptible to water and oxygen corrosion than the metal layer The edge of the organic functional layer is exposed outside the back electrode, thereby improving the lifetime and uniformity of light emission of the device.

The double-layer isolation column in the organic electroluminescence device provided by the invention can more effectively divide the second electrode, the device emits light evenly, and the service life is also improved.

Another technical scheme of the present invention provides a kind of preparation method of organic electroluminescence device, and this method comprises the following steps:

① Deposit a transparent conductive film on a transparent substrate as the first electrode of the device, and photoetch a set of phases on the first electrode

Straight lines that are parallel to each other and separated;

② Coat the first layer of organic insulating material on the above-mentioned first electrode pattern, expose after pre-baking, and the exposure pattern is mesh

structure or strip structure;

③ Coating the second layer of organic insulating material on the above-mentioned first layer of exposed organic insulating material, and applying the second layer of organic insulating material after pre-baking

The second layer of organic insulating material is subjected to overlay exposure, and the exposure pattern is a group of mutual electrodes perpendicular to the first electrode pattern.

Parallel and divided straight lines, the line width is slightly narrower than the first layer line width and the position is centered on it;

④The top-down wet development is carried out on the above two exposed organic insulating layers. After development, the first isolation column

The cross-section of the line on the first floor forms a shape with a small top and a large bottom, and the cross-section of the line on the second layer of the isolation column forms a shape with a large top and a small bottom

, its hypotenuse has two angles α, β that are gradually retracted, and α>β, baked to make the above two layers

The isolation column is completely cured;

5. continue to deposit an organic functional layer on the above-mentioned pattern with double-layer spacers and the first electrode;

⑥ Continue to deposit a metal layer on the organic functional layer as the second electrode of the device.

Another technical solution of the present invention is to provide another method for preparing an organic electroluminescent device, the method comprising the following steps:

① Deposit a transparent conductive film on a transparent substrate as the first electrode of the device, and photoetch a set of phases on the first electrode

Straight lines that are parallel to each other and separated;

② Coating the first layer of organic insulating material on the above-mentioned first electrode pattern, pre-baking but not exposing;

③ Coating the second layer of organic insulating material on the above first layer of organic insulating material, and after pre-baking, the second layer of organic insulating material

The insulating material is exposed, and the exposure pattern is a group of parallel and separated electrodes perpendicular to the first electrode pattern

Straight line, wet development makes the second layer form a line with a cross section with a large top and a small shape;

④ Overlay exposure is carried out on the above-mentioned first layer of organic insulating material. The exposure pattern is a network structure or a strip structure, and the line

The width is slightly wider than the width of the second layer. After wet development, the cross-section of the first layer of the isolation column forms a small top and a large bottom.

Shape, the hypotenuse of the cross-section of the second layer of the isolation column has two gradually inward angles α, β, and α

＞β, bake to fully cure the above two layers of spacers;

5. continue to deposit an organic functional layer on the above-mentioned pattern with double-layer spacers and the first electrode;

⑥ Continue to deposit a metal layer on the organic functional layer as the second electrode of the device.

The preparation method of the organic electroluminescent device provided by the invention has the following advantages:

(1) The process is simple, and the double-layer isolation column is only baked at high temperature at the end, which is mentioned in US20020008467A1

Compared with the technical scheme proposed, the technological process is shortened, and the time for preparing double-layer isolation columns is shortened by 10-30%.

Can greatly improve production efficiency and reduce production costs;

(2) The process is less, which saves equipment investment cost and production management cost accordingly, and is more suitable for domestic construction

  A production line with small investment scale and flexible production;

(3) Continuous coating of two layers of organic insulating materials, and the second layer of insulating columns in the process of preparing double-layer isolation columns

The insulating material does not contact the surface of the first electrode in the light-emitting area, so that the preparation process of the isolation column pollutes the light-emitting area

Minimized, it is beneficial to improve the overall performance of the device, and the yield can easily reach a high level;

(4) The cross-sectional hypotenuse of the second-layer line of the isolation column prepared by this process has two gradually adducting angles

Degree α, β, because the existence of β angle makes the evaporation angle and evaporation thickness of the metal back electrode more tolerant

Large increase, and by using different evaporation angles of the organic functional layer and the metal back electrode, it can be achieved

The back electrode fully covers the organic functional layer, avoiding the organic functional layer that is more susceptible to water and oxygen corrosion than the metal layer.

The edge of the energy layer is exposed outside the back electrode, thereby improving the lifetime and uniformity of light emission of the device.

The preparation method provided by the present invention is a process method for preparing double-layer isolation columns by coating an organic insulating film twice, exposing twice, developing from top to bottom, and curing at a high temperature at the same time. The process is simple, the equipment investment and production cost are low, and the yield high.

The second electrode of the organic electroluminescent device prepared by the method can be effectively separated by the double-layer separation column, the device emits light evenly, and the service life is also improved.

The present invention will become clearer by describing the specific implementation modes and examples below in conjunction with the accompanying drawings.

Description of drawings

Fig. 1 is a cross-sectional view of the structure of the organic electroluminescent device proposed in the background technology EP0732868B1.

Fig. 2 is a cross-sectional view of the structure of the organic electroluminescent device proposed in the background technology EP0732868B1 when the first electrode and the second electrode are short-circuited.

Fig. 3 is a top view of an organic electroluminescent device proposed in background art US20020008467A1.

Fig. 4 is a cross-sectional view of the structure of the organic electroluminescence device in the present invention.

Fig. 5-1a to Fig. 5-3 are the schematic diagrams of the preparation of the double-layer isolation column for the preparation of the organic electroluminescent device in the present invention (consistent with steps ② to ④ of the preferred preparation method 1).

Figure 6-1 to Figure 6-3b are schematic diagrams of the preparation of double-layer spacer columns for organic electroluminescence devices in the present invention (consistent with steps ② to ④ of the preferred preparation method 2).

In the above-mentioned Figures 1 to 6, 1 is the transparent substrate, 2 is the first electrode (anode), 3 is the first layer (insulation base) of the double-layer isolation column in the background technology, and 4 is the single-layer isolation column in the background technology. The second layer (cathode partition wall) of the double-layer spacer column in the column or background technology, 5 is an organic functional layer, 6 is the second electrode (cathode), and 7 is the first layer (insulation base) of the double-layer spacer column of the present invention , 8 is the second layer (cathode partition wall) of the double-layer spacer column of the present invention, 9 is the mask plate 1 for exposure, and 10 is the mask plate 2 for exposure, and the vertically downward arrow among Fig. 5, 6 represents to use UV light The organic insulating layer is exposed.

The content of the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the present invention is not limited to the following preferred embodiments, which are merely illustrative embodiments of the present invention.

Detailed ways

The structure sectional view of the organic electroluminescent device proposed by the present invention is shown in Figure 4, wherein: 1 is a transparent substrate, which can be glass or plastic (flexible substrate); 2 is the first electrode (anode), generally indium tin oxide (hereinafter referred to as ITO), metal oxides such as zinc oxide, tin-zinc oxide, or metals with higher work functions such as gold, copper, and silver, the optimal choice is ITO; 5 is an organic functional layer, which can be a single-layer structure or a multilayer structure Layer structure, when it is a single-layer structure, it is composed of organic electroluminescent materials, which can be metal complexes or organic conjugated polymers, etc. Metal complexes such as octahydroxyquinoline aluminum (hereinafter referred to as Alq ₃ ), etc., organic conjugated polymers Materials mainly include polyacetylene, polythiophene (hereinafter referred to as PEDOT), polycarbazole and its derivatives, such as polyphenylene vinylene vinylene (hereinafter referred to as PPV), etc., which include a light-emitting layer and at least a hole transport layer when it is a multilayer structure. Layer or one layer of the electron transport layer, wherein the light-emitting layer is composed of organic electroluminescent materials, which can be metal complexes or organic conjugated polymers, etc. The material of the hole transport layer is mainly triphenylamine compounds, such as N, N'-di-(1-naphthyl)-N,N'-diphenyl-1,1-biphenyl-4,4-diamine (hereinafter referred to as NPB), N,N'-diphenyl- N, N'-bis(m-methylphenyl)-1,1'-biphenyl-4,4'-diamine (hereinafter referred to as TPD), 4,4',4"-tris(3-methyl Phenylaniline) triphenylamine (hereinafter referred to as MTDATA), etc., the material of the electron transport layer can be a metal complex, such as Alq ₃ , etc.; 6 is the second electrode (cathode), generally lithium, magnesium, calcium, strontium, aluminum, Metals with low work functions such as indium, or their alloys with copper, gold, and silver; 7 is the first layer (insulation base) of the double-layer isolation column, and the material is a photosensitive organic insulating material, generally photosensitive PI, One of positive novolac photoresist, negative cyclized rubber, and chemically amplified photoresist, which is photosensitive PI after optimization; 8 is the second layer (cathode partition wall) of the double-layer isolation column, and the material is photosensitive The organic insulating material is generally a kind of photoresist whose line cross-section can form an inverted trapezoidal shape after photolithography, and is preferably a negative photoresist.

In conjunction with accompanying drawing 5, the preferred preparation method 1 of the organic electroluminescent device that the present invention proposes is described in detail as follows (illustration: the whole preparation process of OLEDs is all implemented in the purification workshop):

① Sputtering a transparent conductive film on the transparent substrate 1 as the first electrode 2 of the device, and photoetching the first electrode 2

A group of parallel and separated straight lines, wherein the transparent substrate 1 can be glass or plastic (flexible substrate

plate), the material of the first electrode 2 is generally ITO, zinc oxide, tin zinc oxide and other metal oxides or gold, copper, silver

For metals with higher work functions, the optimal choice is ITO;

② Spin-coat the first layer of photosensitive organic insulating material on the pattern of the above-mentioned first electrode 2, with a film thickness of 0.5-5 μm,

Generally photosensitive PI, positive novolac photoresist, negative cyclized rubber, chemically amplified photoresist

One, after being preferably photosensitive PI, exposure after pre-baking, the exposure pattern is a network structure (only the device is exposed

The light-emitting area of the pixel point and the lead connection area) or the strip structure (a group of lines perpendicular to the pattern of the first electrode 2

Straight lines parallel to each other and separated), the width of the line is determined by the display resolution, that is, the interval between pixels

Fixed, the line width is 10-50μm;

③ Spin-coat the second layer of photosensitive organic insulating material on the above-mentioned first layer of exposed organic insulating material, with a film thickness of

It is 0.5-5μm, generally in the photoresist whose line cross-section can form an inverted trapezoidal shape after photolithography

A kind of , which is preferably negative-type photoresist, and then overlays the second layer of organic insulating material after pre-baking.

The exposure pattern is a group of parallel and separated straight lines perpendicular to the pattern of the first electrode 2, and the line width ratio

The line width of the first layer is slightly narrow and centered on it, and the line width is 5-45 μm. If you use light that must be medium-baked

The engraving should also be baked in the middle;

④The top-down wet development is carried out on the above two layers of exposed organic insulating material layers, and the preferred developer is

The two layers of organic insulating materials are the same, if they are not the same, they will be developed sequentially from top to bottom. After development, the insulating base 7

The cross-section of the line forms a shape with the top small and the bottom is large, and the cross-section of the cathode partition 8 lines forms a shape with the top large and the bottom small

shape, its hypotenuse has two gradually retracted angles α, β, and α>β, high temperature baking makes the insulating base

7 and the cathode partition wall 8 are completely cured, and the baking temperature is 150-350°C;

5. Continue to deposit the organic functional layer 6 on the above-mentioned pattern with double-layer spacers and the first electrode 2, the organic functional layer

The layer can be a single-layer structure or a multi-layer structure. When it is a single-layer structure, it is composed of organic electroluminescent materials, which can be gold

Metal complexes or organic conjugated polymers, etc., metal complexes such as Alq ₃ , etc., organic conjugated polymer materials are mainly

Organic conjugated polymers including polyacetylene, PEDOT, polycarbazole and their derivatives, such as PPV, etc.; multilayer

The structure includes a light-emitting layer and at least one of a hole-transport layer or an electron-transport layer, wherein light is emitted

The layer is composed of organic electroluminescent materials, which can be metal complexes or organic conjugated polymers, etc., and the hole transport layer

The material is mainly triphenylamine compounds, such as NPB, TPD, MTDATA, etc. The material of the electron transport layer can be

It is a metal complex, such as Alq ₃ , etc.;

6. Continue to vapor-deposit a metal layer on the above-mentioned organic functional layer 5 as the second electrode 6 of the device, and the metal layer is generally

Metals with low work functions such as lithium, magnesium, calcium, strontium, aluminum, indium, or their alloys with copper, gold, and silver.

In conjunction with accompanying drawing 6, the preferred preparation method 2 of the organic electroluminescent device that the present invention proposes is described in detail as follows (illustration: the whole preparation process of OLEDs is all implemented in the purification workshop):

① same as preferred preparation method 1;

② Spin-coat the first layer of photosensitive organic insulating material on the pattern of the above-mentioned first electrode 2, with a film thickness of 0.5-5 μm,

Generally photosensitive PI, positive novolac photoresist, negative cyclized rubber, chemically amplified photoresist

One, after being preferably photosensitive PI, pre-baked but not exposed;

③ Spin-coat the second layer of photosensitive organic insulating material on the above-mentioned first layer of organic insulating material, with a film thickness of 0.5~

5 μm, generally one of the photoresists whose line cross-section can form an inverted trapezoidal shape after photolithography,

After being optimized as a negative photoresist, the second layer of organic insulating material is exposed after pre-baking, and the exposure pattern is the same as

A group of parallel and separated straight lines perpendicular to the pattern of the first electrode 2, with a line width of 5-45 μm, if

The photoresist that needs to be baked in the middle is also baked in the middle, and the wet development makes the second layer form a cross-section with a large upper and a lower

lines of small shapes;

④ Overlay exposure is carried out on the above-mentioned first layer of insulating material, and the exposure pattern is a network structure (only the pixel of the device is exposed

point light-emitting area and lead connection area) or strip structure (a group of mutually perpendicular to the first electrode 2 pattern

Parallel and separated straight lines), the line width is slightly wider than the line width of the cathode partition wall 8, which is 10-50 μm, wet method

After development, the cross-section of the 7 lines of the insulating base forms a shape with a small top and a large bottom, and the cross-section of the 8 lines of the cathode partition

The hypotenuse has two angles α and β that are gradually retracted, and α>β, high temperature baking makes the insulating base 7 and the cathode

The pole partition wall 8 is completely cured, and the baking temperature is 150-350°C;

5. with the preferred preparation method 1;

6. Same as preferred preparation method 1.

Example 1:

(The entire preparation process of OLED is carried out in the purification workshop.) Use UV and lotion containing surfactant to clean and dry the ITO glass with a square resistance of 15Ω. The film thickness of ITO is 170nm. A group of parallel and separated straight lines with a line width of 400 μm and a line gap of 30 μm. Wash and dry again, and then spin-coat the first layer of organic insulating material photosensitive PI DL-1000 with a film thickness of 1.5 μm, and bake in a convection oven at 125°C for 25 minutes. The first layer is exposed but not developed, and the exposure pattern is a network structure, that is, only the light-emitting area and the lead connection area of the pixel point of the device are exposed. The width of the line parallel to the ITO line is 45 μm, and the line perpendicular to the ITO line The width is 40 μm. Then continue to spin-coat the second layer of insulating material negative photoresist ZPN1168-30 on the first organic insulating layer with a film thickness of 3 μm. After baking in a convection oven at 95°C for 15 minutes, the second layer is exposed through an overlay process. The exposure pattern is a group of parallel and separated straight lines perpendicular to the ITO lines, and the second layer of lines is on the first layer. The position is centered, the width is slightly narrower than the line width of the first layer, and the line width is 25 μm. After baking in a convection oven at 95° C. for 10 minutes, the two layers were developed together for 60 seconds with a 2.38% tetramethylammonium hydroxide (hereinafter referred to as TMAHO) solution to form different patterns. Bake in a convection oven at 250°C for 30 minutes to completely cure the insulating base and the cathode partition. The sides have two progressively retracting angles α, β, α=70°, β=45°. Finally, the organic functional layer and the metal layer are vapor-deposited in a vacuum furnace with a vacuum degree of 10 ^-4 Pa or higher. The organic functional layer is composed of CuPc, NPB and Alq ₃ in turn, and the film thicknesses are 20nm, 50nm and 50nm respectively. The metal layer is composed of LiF/Al, and the film thicknesses are 1nm and 400nm, respectively. Encapsulate the device in an inert atmosphere. The lighting voltage of the device is 3V, the light is uniform, and the life of the device is more than 5000h. Example 2:

(The entire preparation process of OLED is carried out in the purification workshop.) Use UV and lotion containing surfactant to clean and dry the ITO glass with a square resistance of 5Ω. The ITO film thickness is 200nm. A group of parallel and separated straight lines with a line width of 200 μm and a line gap of 20 μm. Wash and dry again, and then spin-coat the first layer of organic insulating material photosensitive PI DL-1000 with a film thickness of 1.2 μm, and bake in a convection oven at 125°C for 25 minutes. Immediately continue to spin-coat the second layer of organic insulating material negative photoresist Tlor-n on the first organic insulating layer with a film thickness of 4 μm, and bake in a hot plate at 110° C. for 90 s. Then the second layer is exposed, the exposure pattern is a group of parallel and separated straight lines perpendicular to the ITO lines, the line width is 15 μm, and baked in a hot plate at 110°C for 60s. Use 2.38% TMAHO solution to develop the second layer of negative photoresist for 30 seconds, and then the pattern can be displayed. The first layer is exposed through an overlay process, and the exposure lines are straight lines under the second layer and slightly wider than the lines of the second layer, and the line width is 30 μm. The first layer was developed for another 30 s with 2.38% TMAHO solution. Bake on a hot plate at 250°C for 20 minutes to completely cure the insulating base and the cathode partition. The sides have two progressively retracting angles α, β, α=70°, β=45°. Finally, the organic functional layer and the metal layer are vapor-deposited in a vacuum furnace with a vacuum degree of 10 ^-4 Pa or higher. The organic functional layer is composed of CuPc, NPB and Alq ₃ in turn, and the film thicknesses are 20nm, 35nm and 40nm respectively. The metal layer is sequentially composed of Mg:Ag alloy (evaporation rate ratio 10:1, alloy mass ratio 4:1) and Ag, and the film thicknesses are 150nm and 300nm respectively. Encapsulate the device in an inert atmosphere. The lighting voltage of the device is 3V, the luminescence is uniform, the luminous efficiency is 4.5lm/W when the current density is 20mA/cm ² , and the lifetime of the device is more than 5000h.

Although the present invention has been described in conjunction with preferred embodiments, the present invention is not limited to the above-mentioned embodiments and accompanying drawings, especially the shape of the line cross-section of the second layer 8 of the isolation column is not limited to those shown in accompanying drawings 4 to 6 , as long as the hypotenuse has two gradually inward angles, and the double spacer structure of the organic electroluminescent device proposed by the present invention can also be prepared by other methods. It should be understood that various modifications and improvements can be made by those skilled in the art under the guidance of the concept of the present invention, and the appended claims outline the scope of the present invention.

Claims (11)

1. organic electroluminescence device, constitute X-Y two-dimension addressing matrix by one group of first electrode (2) parallel to each other with one group of second electrode (6) parallel to each other vertical with first electrode (2), it has a plurality of pixels, each pixel comprises first electrode (2) and second electrode (6) and is clipped in organic function layer (5) between described two electrodes, on described first electrode (2) figure, have one group with the perpendicular double-deck insulated column that is parallel to each other and separates of first electrode pattern with insulating properties, wherein the figure of insulated column ground floor (7) is network structure or list structure, the cross section of lines has up-small and down-big shape, the lines of the insulated column second layer (8) on the lines of insulated column ground floor (7) and the position placed in the middle, it is characterized in that: the cross section of the insulated column second layer (8) lines is up big and down small shape, its hypotenuse has two interior gradually angle [alpha] of receiving, β, and α＞β.

2. according to the organic electroluminescence device of claim 1, it is characterized in that described α angle is 45 °～80 °, described β angle is 20 °～60 °.

3. according to the organic electroluminescence device of claim 1 or 2, it is characterized in that, the material of described double-deck insulated column ground floor (7), the second layer (8) is the Photosensitive organic insulating material, and described second layer organic insulating material is for applying, expose, all do not influencing when developing described ground floor organic insulating material light sensitivity and inhomogeneity material.

4. according to the organic electroluminescence device of claim 3, it is characterized in that the material of described insulated column ground floor (7) is a kind of in Photosensitive polyimides, eurymeric novolac photoresist, minus thermoprene, the chemical amplification type photoresist.

5. according to the organic electroluminescence device of claim 3, it is characterized in that the material of the described insulated column second layer (8) is that the lines cross section can form a kind of in the up big and down small photoresist that falls trapezoidal shape after the photoetching.

6. according to the organic electroluminescence device of claim 3, it is characterized in that the material of described insulated column ground floor (7) is the Photosensitive polyimides, the material of the described insulated column second layer (8) is a negative photoresist.

7. according to the organic electroluminescence device of claim 1, it is characterized in that described organic function layer is single layer structure or is sandwich construction.

8. method for preparing the described organic electroluminescence device of claim 1, this method may further comprise the steps:

1. go up first electrode (2) of deposit transparent conductive film at transparency carrier (1), make first electrode (2) by lithography one group of vertical element that is parallel to each other and separates as device;

2. on above-mentioned first electrode (2) figure, apply the ground floor organic insulating material, preceding baking post-exposure, exposure figure is network structure or list structure;

3. on the organic insulating material of overexposure, apply second layer organic insulating material at above-mentioned ground floor, the alignment exposure is carried out to second layer organic insulating material in preceding baking back, exposure figure for and one group of perpendicular vertical element that is parallel to each other and separates of first electrode (2) figure, live width is slightly narrower and the position is placed in the middle thereon than ground floor line thickness;

4. above-mentioned two-layer organic insulating material layer through overexposure is carried out top-down wet development, the cross section of insulated column ground floor (7) lines forms up-small and down-big shape after developing, the cross section of the insulated column second layer (8) lines forms up big and down small shape, its hypotenuse has two interior gradually angle [alpha], β that receive, and α＞β, baking makes above-mentioned two-layer insulated column full solidification;

5. on above-mentioned figure with double-deck insulated column and first electrode (2), continue deposit organic function layer (5);

6. on above-mentioned organic function layer (5), continue second electrode (6) of deposited metal as device.

9. method for preparing the described organic electroluminescence device of claim 1, this method may further comprise the steps:

1. go up first electrode (2) of deposit transparent conductive film at transparency carrier (1), make first electrode (2) by lithography one group of vertical element that is parallel to each other and separates as device;

2. on above-mentioned first electrode (2) figure, apply the ground floor organic insulating material, preceding baking but do not expose;

3. on above-mentioned ground floor organic insulating material, apply second layer organic insulating material, expose to second layer organic insulating material in preceding baking back, exposure figure is and one group of perpendicular vertical element that is parallel to each other and separates of first electrode (2) figure that wet development makes the second layer form the lines that cross section has up big and down small shape;

4. above-mentioned ground floor organic insulating material is carried out the alignment exposure, exposure figure is network structure or list structure, live width is slightly wideer than the width of the second layer, the cross section of insulated column ground floor (7) lines forms up-small and down-big shape behind the wet development, the hypotenuse of the insulated column second layer (8) lines cross section has two interior gradually angle [alpha], β that receive, and α＞β, baking makes above-mentioned two-layer insulated column full solidification;

5. on above-mentioned figure with double-deck insulated column and first electrode (2), continue deposit organic function layer (5);

6. on above-mentioned organic function layer (5), continue second electrode (6) of deposited metal as device.

10. according to Claim 8 or the preparation method of 9 organic electroluminescence device, it is characterized in that, step 4. described in behind the wet development baking to make the completely crued baking temperature of above-mentioned two-layer insulated column be 150～350 ℃.

11. according to Claim 8 or the preparation method of 9 organic electroluminescence device, it is characterized in that, step 2., the method that all can adopt rotation to apply of the applied in two coats organic insulating material described in 3..

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