[0050] Correspondingly, the embodiments of the present invention also provide a method for preparing the organic electroluminescent device described above. The process flow diagram of the method is as follows image 3 Therefore, see also Figures 1 to 2 , the method includes the following steps:
[0051] S01. Provide a light-transmitting substrate layer 1;
[0052] S02. Preparation of anode layer 2: plating anode layer 2 on one surface of light-transmitting substrate layer 1 in step S01;
[0053] S03. Preparation of organic functional layer 3: in step S02, the surface of anode layer 2 opposite to the bonding surface of light-transmitting substrate layer 1 is sequentially plated with hole injection layer 31, hole transport layer 32, light-emitting layer 33, and electron transport layer 34 , an electron injection layer 35 to form an organic functional layer 3;
[0054] S04. Preparation of cathode layer 4: plating cathode layer 4 on the outer surface of organic functional layer 3 in step S03;
[0055] S05. Prepare an organic barrier layer 5 and an inorganic barrier layer 6 that are alternately stacked and combined with the outer surface of the cathode layer 4:
[0056] In the vacuum coating system, the organic material functional layer 5 is formed by doping and co-evaporating the organic material barrier layer material on the outer surface of the cathode layer 4;
[0057] In a vacuum system, the inorganic barrier layer 6 is formed by magnetron sputtering the inorganic barrier layer material on the outer surface of the organic functional layer 5;
[0058] The steps of preparing the organic functional layer 5 and the inorganic barrier layer 6 are sequentially repeated on the outer surface of the inorganic barrier layer 6 .
[0059] Specifically, in the above step S01, the structure, material and specifications of the light-transmitting substrate layer 1 are as described above, and for the sake of space, they will not be repeated here. In addition, in the S01 step, the pre-processing steps of the light-transmitting substrate layer 21, such as cleaning and decontamination steps, are also included.
[0060] In the above step S02 , the substrate is placed in a magnetron sputtering system to form a film by sputtering on the surface of the substrate to form the anode layer 2 . The sputtering conditions can adopt the conventional process conditions in the art.
[0061] Preferably, before performing the following step S03, the method further includes performing plasma treatment on the anode layer 2 in step S02: placing the substrate plated with the anode layer 2 in a plasma treatment chamber for plasma treatment. The plasma treatment conditions may adopt conventional process conditions in the art. After plasma treatment, the anode layer 2 can effectively improve the anode work function and reduce the injection barrier of holes.
[0062] Of course, a transparent substrate plated with an anode such as ITO can also be directly selected, and the transparent substrate plated with an anode is subjected to preliminary pretreatment, such as cleaning, plasma treatment, and the like, and then the following step S03 is performed.
[0063] In the above step S03, after the hole transport layer 31 is plated on the outer surface of the anode layer 2, the hole transport layer 32, the light-emitting layer 33, the electron transport layer 34, and the electron injection layer 35 are sequentially evaporated on the outer surface of the hole transport layer 31. , the materials selected for plating the layers and the uniform thickness are as described above. The process conditions involved in evaporating each layer may be in accordance with the conventional conditions in the art.
[0064] Further, when the organic functional layer 3 further contains an electron blocking layer 36 and a hole blocking layer 37, such as figure 2 shown. Therefore, in this step S03, the step of plating the electron blocking layer 36 after the hole transport layer 32 and the plating of the light emitting layer 33 also includes the step of plating the electron blocking layer 36, and after the step of plating the light emitting layer 33 and the plating of the electron transport layer 34, it also includes plating the hole blocking layer 37 A step of. The materials and thicknesses selected for the plating of the electron blocking layer 36 and the hole blocking layer 37 are as described above, respectively. The process conditions involved in evaporating the two layers can be in accordance with the conventional conditions in the art.
[0065] In the above step S04 , the substrate coated with the organic functional layer 3 is placed in a coating system, and the cathode material described above is used as the coating source to coat the outer surface of the organic functional layer 3 to form the cathode layer 4 . The vapor deposition conditions can adopt the conventional process conditions in the art.
[0066] In the above step S05, in the step of plating the organic functional layer 5, the organic functional layer 5 is formed by vapor deposition on the outside of the cathode layer 4 prepared in the above step S04 using the material selected for the organic functional layer 5 as a plating source.
[0067] Wherein, the material selected for the organic functional layer 5 is as described above, and the material preferably includes a hole transport material and an electron transport material doped with each other, wherein the hole transport material accounts for 40% of the total mole percent of the organic blocking layer material. %~60%. The hole transport material and the electron transport material are as described above, and in order to save space, they will not be repeated here. The organic materials doped with each other are co-evaporated to form the organic functional layer 5 . Of course, the organic material selected for the organic functional layer 5 can also be formed by vapor deposition using other organic materials commonly used in the art.
[0068] In a preferred embodiment, the process conditions for forming the organic functional layer 5 by evaporation are as follows:
[0069] The vacuum degree during co-evaporation of the materials selected for the organic functional layer 5 is 1×10 -5 Pa~1×10 -3 Pa, the evaporation rate of the material is The preferred vapor deposition process conditions can make the formed organic functional layer 5 more flat and dense. The evaporation time under the evaporation process conditions can be flexibly adjusted and controlled according to the thickness of the organic functional layer 5 .
[0070] In the above step S05, in the step of plating the inorganic barrier layer 6, the material selected for the inorganic barrier layer 6 plating is the inorganic material described above, and its materials include telluride, selenide and oxide; wherein, the selenide is The weight percentage of the total weight of the inorganic barrier material is 10% to 30%, the weight percentage of the telluride to the total weight of the inorganic barrier material is 10% to 30%, and the types of telluride, selenide and oxide are respectively As mentioned above, in order to save space, details are not repeated here.
[0071] In a preferred embodiment, the process conditions for forming the inorganic barrier layer 6 by magnetron sputtering are as follows:
[0072] The background vacuum in magnetron sputtering is 1×10 -5 Pa~1×10 -3 Pa. Wherein, the inert gas introduced in the magnetron sputtering can be an inert gas commonly used in the art, such as Ar. The preferred process conditions of magnetron sputtering can make the formed inorganic barrier layer 6 more dense, and the lamination and bonding with the above-mentioned organic functional layer 5 are more tightly and firmly. Under the process conditions of the magnetron sputtering, the magnetron sputtering time can be flexibly adjusted and controlled according to the thickness of the inorganic barrier layer 6 .
[0073] In the above-mentioned step S05, when the steps of repeatedly preparing the organic functional layer 5 and the inorganic barrier layer 6 are sequentially performed on the outer surface of the inorganic barrier layer 6, the number of times of repeating the preparation of the organic functional layer 5 and the inorganic barrier layer 6 is preferably 4 to 6. Of course, as mentioned above, the number of times of repeating the preparation of the organic functional layer 5 and the inorganic barrier layer 6 may be more than 1 time, less than 3 times or more than 7 times, and the specific number of stacking can be based on the organic electroluminescent device The light-emitting wavelength can be adjusted flexibly, so that the organic electroluminescent device can achieve the best light-emitting effect.
[0074] As can be seen from the above, the above-mentioned preparation method of the organic electroluminescent device prepares alternately stacked organic barrier layers 5 and inorganic barrier layers 6 on the outer surface of the cathode layer by evaporation and sputtering, respectively, so that the alternately stacked organic barrier layers are combined. 5 and the inorganic barrier layer 6 play a synergistic effect, effectively blocking the erosion of the organic electroluminescent device by active substances such as water and oxygen. In addition, by adjusting the process conditions of the coating, the organic barrier layer 5 and the inorganic barrier layer 6 are closely combined, flat and dense, thereby significantly prolonging the service life of the OLED device. The preparation method of the organic electroluminescent device has simple and mature procedures, easily controllable conditions, high yield of finished products, effectively improves production efficiency, reduces production cost, and is suitable for industrial production.
[0075] The organic electroluminescent device and the preparation method thereof according to the embodiments of the present invention will now be further described in detail with reference to specific examples.
