OLED vertical evaporation device

Abstract

The utility model discloses an OLED (Organic Light Emitting Diode) vertical evaporation device, which is characterized in that a plurality of crucible nozzles, a plurality of crucible upper pipelines and a plurality of crucible bottoms are sequentially connected, a crucible upper partition plate is arranged between every two crucible upper pipelines, and an acute angle is formed between each crucible nozzle and the horizontal direction; organic material steam sprayed by a crucible nozzle is sprayed on a glass substrate and a fine metal mask which are vertically arranged; the upper heating wire is arranged on the outer wall of the crucible upper pipeline, and the bottom heating wire is arranged on the outer wall of the crucible bottom; a bottom partition plate is arranged in the bottom of the crucible, the organic material is arranged in the bottom of the crucible, and the organic material is partitioned by the bottom partition plate. According to the utility model, the phenomenon that the center area of the FMM droops due to weight is reduced, the mesh surface of the FMM is not deformed and droops to be tightly and flatly attached to the substrate, the OLED evaporation yield is greatly reduced from 30% to 80%, meanwhile, the distance (TS) between glass and a line source nozzle is greatly shortened, and the utilization rate of OLED materials is improved from 5% to 40%.

Description

Technical Field

[0001] The utility model belongs to the technical field of OLED and relates to an OLED vertical evaporation device. Background Art

[0002] The existing solution in the OLED industry is to increase the "rigidity" of the FMM substrate itself, and to increase the "prestress and pre-structure" of the evaporation platform to resist gravity deformation. Etching RGB sub-pixel holes in the Invar36 (nickel alloy) material allows the light-emitting organic material to be deposited through the mask and deposited at the desired position on the substrate (the denser the holes, the smaller the generated pixels and the higher the resolution). It is used to solve the pixel array distribution of the RGB primary colors of the evaporated organic material, thereby realizing a fine metal mask, namely Fine Metal Mask (FMM);

[0003] Invar is a nickel-iron alloy, which has small expansion coefficient, magnetism, low thermal conductivity, high plasticity and toughness. During the evaporation process, the temperature of the material will be transferred to the mask. The thermal deformation of the mesh is small. To ensure flatness and fit with the substrate, the evaporation machine has a permanent magnet to adsorb the mask. The mesh and the substrate fit well, so the mesh needs to be magnetic; high plasticity, can be made ultra-thin, and can be processed by etching. High toughness, the life of the mask is guaranteed, but the FMM technology has physical limitations. Because the organic material releases heat during the evaporation process, the temperature of the FMM and the glass rises. The FMM becomes longer after thermal expansion, forming a gap between the glass and the glass, which will cause RGB color mixing. However, the FMM and glass substrate of the 8.5-generation line cannot avoid sagging due to the influence of gravity. Therefore, the value of the FMM itself in the OLED panel manufacturing process is mainly "forming pixels", "maintaining pixel resolution PPI", "ensuring pixel yield" and other indicators cannot be guaranteed by yield, see Figure 1 As shown in the figure, glass substrate 01 and fine metal mask 02;

[0004] The widely used "horizontal evaporation" cannot break through the physical limit by increasing the "rigidity" of the FMM substrate itself and adding "prestress and pre-structure" to the evaporation platform to resist gravity deformation. The high-precision fine metal mask (FMM) on the 8.5-generation line still has unacceptable "center of gravity droop". The biggest problems in the OLED evaporation process are "thickness uniformity", evaporation position accuracy, and pixel integrity. Once the FMM board is deformed by gravity, the thickness and properties of the OLED evaporation deposition on the entire glass substrate will obviously be "inconsistent", which will greatly restrict the OLED yield. In addition, in order to obtain better film thickness uniformity, horizontal evaporation causes the distance from the substrate to the evaporation source to be greater than 800mm, resulting in an OLED material utilization rate of less than 5%, and the economic efficiency of horizontal evaporation is poor. Utility Model Content

[0005] This application is mainly to solve the problem of low yield of OLED evaporation machine when AMOLED is shifting from 6.5-generation line (OLED smartphones mainly use 6th-generation half-cut horizontal evaporation technology) to 8.5-generation line (the size of the glass substrate of the 8.5-generation line is 2200*2500mm, and the products can cover smartphones and smart IT panels. The output of the 8.5-generation line is more economical than the 6th-generation line. Taking 13.3-inch panels as an example, the 6th-generation line (1500mm×1850mm) can produce 48 pieces, and the 8.5th-generation (2200mm×2500mm) can produce 96 pieces. The 6th-generation production line has obvious limitations in production efficiency and cost control.) The current mainstream solution for AMOLED is the linear evaporation source plus FMM technology solution. As the substrate size is super large, the glass substrate and FMM have sagging problems due to gravity, resulting in wrinkles on the mesh surface. The Mask itself cannot be flattened due to the sagging of the glass and the mesh surface, resulting in an extremely short life of the FMM. However, due to wrinkles and sagging in the high PPI FMM pixel holes, the organic material of the red pixel is evaporated onto the green and blue pixel positions, forming color spots, resulting in a yield of less than 20% in the production of large-size panels. At the same time, the utilization rate of OLED materials is less than 6% (because in order to ensure the uniformity of film thickness and shadow control, the distance from the glass substrate to the evaporation source is 800~1200mm). The low yield of large-size products and the low utilization rate of OLED materials lead to excessively high product costs. This is also the main reason why AMOLED companies have been suffering losses.

[0006] This application uses a vertical evaporation solution. The glass substrate and the fine metal mask FMM are in a vertical state, the linear evaporation source is on the side, and the material is horizontally evaporated onto the substrate. The vertical solution fundamentally solves the problem of sagging of the glass and FMM mesh, and then solves the problems of FMM life and color spots, and increases the utilization rate of OLED materials to >50%, thereby greatly improving the feasibility of AMOLED turning to an ultra-large size solution in the cost reduction solution, which is conducive to AMOLED companies turning losses into profits.

[0007] In view of the above situation and problems, the technical solution of the utility model is an OLED vertical evaporation device, including a crucible nozzle, an upper crucible pipe, an upper crucible partition, a crucible bottom, a bottom heating wire, an upper heating wire, a bottom partition, a cooling box and an organic material, wherein:

[0008] The crucible nozzle, the crucible upper pipe and the crucible bottom are connected in sequence, and a plurality of them are provided. An upper crucible partition is provided between each crucible upper pipe. The crucible nozzle is provided at an acute angle to the horizontal direction. The organic material vapor sprayed from the crucible nozzle is sprayed onto the vertically arranged glass substrate and the fine metal mask.

[0009] The upper heating wire is arranged on the outer wall of the upper pipe of the crucible, and the bottom heating wire is arranged on the outer wall of the bottom of the crucible;

[0010] A bottom partition plate is arranged at the bottom of the crucible, the organic material is arranged at the bottom of the crucible, and the bottom partition plate separates the organic material;

[0011] The cooling box is arranged outside all the crucible upper pipes and the bottom of the crucible to cool them.

[0012] Preferably, the bottom heating wire and the upper heating wire are both configured to be wavy and are made of tantalum wire.

[0013] Preferably, the crucible nozzle is 3° to 15° with respect to the horizontal direction.

[0014] Preferably, the distance between the crucible nozzles is 2000 mm to 2500 mm.

[0015] Preferably, the number of the crucible nozzles is 50 to 99.

[0016] Preferably, the evaporation path of the crucible nozzle is:

[0017]

[0018] Among them, y is the evaporation path of the organic material; θ is the angle between the organic material and the horizontal direction when it is ejected from the crucible nozzle, that is, the evaporation angle; n is the ratio of the height to the diameter of the crucible nozzle; k is the formula coefficient, k=V0 / R 2 , V0 is the straight-line distance from the crucible nozzle to the glass substrate, and R is the distance from the crucible nozzle to the glass substrate when the evaporation angle is θ.

[0019] Preferably, n is 3-5.

[0020] Preferably, the straight-line distance from the crucible nozzle to the glass substrate is 105 mm to 380 mm.

[0021] Preferably, the bottom partition plate divides the bottom of the crucible into an upper layer and a lower layer, and the space ratio between the upper layer and the lower layer is 2:1.

[0022] Preferably, a buckle is provided on the side wall of the cooling box to clamp the upper pipe of the crucible at a preset position.

[0023] The utility model has the following specific beneficial effects: the line source scheme of vertical evaporation makes the fine metal mask (FMM) substrate required for R / G / B OLED organic evaporation perpendicular to the ground. Compared with the horizontal evaporation machine, the vertical evaporation device can reduce the sagging phenomenon of the central area of ​​the FMM due to weight, and ensure that the FMM mesh surface has no deformation and sagging and fits tightly and flatly with the substrate, which greatly improves the OLED evaporation yield from 30% to 80%, and greatly shortens the distance (TS) between the glass and the line source nozzle, improves the utilization rate of OLED materials from 5% to 40%, greatly reduces the cost of OLED materials, and extends the service life of FMM, thereby reducing the overall cost of 8.5-generation line products. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a glass substrate and mask layout for horizontal evaporation of OLED in the prior art;

[0025] Figure 2 This is a structural exploded view of an OLED vertical evaporation device according to an embodiment of the utility model;

[0026] Figure 3 This is a structural diagram of the evaporation part of the OLED vertical evaporation device according to an embodiment of the utility model;

[0027] Figure 4 This is an overall structural diagram of an OLED vertical evaporation device according to an embodiment of the present utility model. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0029] On the contrary, the present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention as defined by the claims. Further, in order to make the public have a better understanding of the present invention, some specific details are described in detail in the following detailed description of the present invention. Those skilled in the art can fully understand the present invention without the description of these details.

[0030] See also Figure 2-Figure 4 The utility model comprises a crucible nozzle 03, a crucible upper pipe 04, a crucible upper partition 05, a crucible bottom 06, a bottom heating wire 07, an upper heating wire 08, a bottom partition 10, a cooling box 12 and an organic material 14, wherein:

[0031] The crucible nozzle 03, the crucible upper pipe 04 and the crucible bottom 06 are connected in sequence, and a plurality of them are provided. A crucible upper partition plate 05 is provided between each crucible upper pipe 04. The crucible nozzle 03 is provided at an acute angle to the horizontal direction. The organic material 14 vapor sprayed from the crucible nozzle 03 is sprayed onto the vertically provided glass substrate 01 and the fine metal mask 02.

[0032] The upper heating wire 08 is arranged on the outer wall of the upper pipe 04 of the crucible, and the bottom heating wire 07 is arranged on the outer wall of the bottom 06 of the crucible;

[0033] A bottom partition plate 10 is disposed in the bottom 06 of the crucible, and an organic material 14 is disposed in the bottom 06 of the crucible, and the bottom partition plate 10 separates the organic material 14;

[0034] The cooling box 12 is arranged outside all the crucible upper pipes 04 and the crucible bottom 06 to cool them.

[0035] The bottom heating wire 07 and the upper heating wire 08 are both set to be wavy, made of tantalum wire, and have a heating capacity of 0~800°C. The bottom heating wire 07 covers the bottom crucible in an annular shape to heat the material evenly.

[0036] The crucible nozzle 03 is 3° to 15° with respect to the horizontal direction. The distance between the crucible nozzles 03 is 2000 mm to 2500 mm. The number of the crucible nozzles 03 is 50 to 99.

[0037] In order to counteract the influence of the material on the vapor pressure of the organic material 14, the crucible nozzle 03 is designed with the above tilt angle, distance and number. The number of the crucible nozzles 03 solves the problem of uniform film thickness. The diameter and height of the crucible nozzle 03 are creatively designed to ensure that the organic material 14 evaporated silicon base is concentrated as much as possible within a certain evaporation path range. The evaporation path of the crucible nozzle 03 is:

[0038] Wherein, y is the evaporation path of the organic material 14; θ is the angle between the organic material 14 and the horizontal direction when it is ejected from the crucible nozzle 03, i.e., the evaporation angle; n is the ratio of the height to the diameter of the crucible nozzle 03; k is the formula coefficient, k=V0 / R 2 , V0 is the straight-line distance from the crucible nozzle 03 to the glass substrate 01, and R is the distance from the crucible nozzle 03 to the glass substrate 01 when the evaporation angle is θ.

[0039] In a specific embodiment, n is 3-5. When the organic material 14 passes through the crucible nozzle 03, it is directly related to the diameter and path length (the height of the crucible nozzle 03), and also directly determines the movement trajectory of the organic material 14. In theory, the larger the n value, the better (the smaller the evaporation range, the more uniform the film thickness distribution), but the larger the n value, the greater the pressure in the evaporation source crucible, which can easily lead to material cracking and denaturation, resulting in a serious decline in product performance. When n is set to 3-5, the overall uniformity of the film on the surface of the glass substrate 01 is less than 2%, and the Shadow can be controlled within <5~10μ.

[0040] Since the linear evaporation source adopts a crucible nozzle 03 design with a high n value, the horizontal distance TS between the glass substrate 01 and the crucible nozzle 03, i.e. the straight-line distance, is set at 105~380mm. The distance from the crucible nozzle 03 to the glass substrate 01 is greatly reduced, and the proportion of the organic material 14 evaporated to the invalid area is greatly reduced, thereby improving the material utilization rate.

[0041] The upper crucible pipe 04 is used to balance the vapor pressure of the organic material 14. The upper crucible pipe 04 separates the channels of each crucible nozzle 03 through the upper crucible partition 05 to prevent the organic material vapor 13 from being affected by gravity and interfering with the operation of the adjacent crucible nozzle 03, thereby ensuring that the organic material vapor 13 passes through each crucible nozzle 03 stably and ensuring that the uniformity of the evaporated film thickness is less than 2%.

[0042] The bottom 06 of the crucible is cylindrical and is designed with two layers, the upper and lower layers are separated by a space ratio of 2:1, so that the organic material 14 can avoid occupying the bottom of the crucible 06 due to the influence of gravity and heating and melting. The upper pipe 04 of the crucible is connected to the bottom 06 of the crucible by threads.

[0043] The cooling box 12 of the evaporation source is made of stainless steel and has a closed channel inside. The circulating cooling water continuously removes heat. The amount of heat removed from the linear evaporation source is constant. The organic material 14 is converted from a solid state to a vapor state by controlling the heat generated by the upper heating wire 08 and the bottom heating wire 07, thereby forming an organic material vapor 13. The organic material vapor 13 is cooled and deposited into a thin film on the glass substrate 01. The cooling box 12 limits the position of the crucible upper pipe 04 in the cooling box 12 through the buckle 11. For details, see Figure 4 The bottom 06 of the crucible loaded with the organic material 14 is connected to the upper pipe 04 of the crucible, and the whole is placed in the cooling box 12. It is heated by the upper heating wire 08 and the bottom heating wire 07, and the organic material vapor 13 is ejected from the horizontal crucible nozzle 03 to form a film on the surface of the glass substrate 01.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. OLED vertical evaporation device, characterized in that: The invention comprises a crucible nozzle, an upper crucible pipe, an upper crucible partition, a crucible bottom, a bottom heating wire, an upper heating wire, a bottom partition, a cooling box and an organic material, wherein: The crucible nozzle, the crucible upper pipe and the crucible bottom are connected in sequence, and a plurality of them are provided. An upper crucible partition is provided between each crucible upper pipe. The crucible nozzle is provided at an acute angle to the horizontal direction. The organic material vapor sprayed from the crucible nozzle is sprayed onto the vertically arranged glass substrate and the fine metal mask. The upper heating wire is arranged on the outer wall of the upper pipe of the crucible, and the bottom heating wire is arranged on the outer wall of the bottom of the crucible; A bottom partition plate is arranged at the bottom of the crucible, the organic material is arranged at the bottom of the crucible, and the bottom partition plate separates the organic material; The cooling box is arranged outside all the crucible upper pipes and the bottom of the crucible to cool them.

2. The OLED vertical evaporation device according to claim 1, characterized in that: The bottom heating wire and the upper heating wire are both arranged in a wave shape and are made of tantalum wire.

3. The OLED vertical evaporation device according to claim 1, characterized in that: The crucible nozzle is 3° to 15° with respect to the horizontal direction.

4. The OLED vertical evaporation device according to claim 1, characterized in that: The distance between the crucible nozzles is 2000 mm to 2500 mm.

5. The OLED vertical evaporation device according to claim 1, characterized in that: The number of the crucible nozzles is 50 to 99.

6. The OLED vertical evaporation device according to claim 1, characterized in that: The straight-line distance from the crucible nozzle to the glass substrate is 105 mm to 380 mm.

7. The OLED vertical evaporation device according to claim 1, characterized in that: The bottom partition plate divides the bottom of the crucible into an upper layer and a lower layer, and the space ratio between the upper layer and the lower layer is 2:

1.

8. The OLED vertical evaporation device according to claim 1, characterized in that: The side wall of the cooling box is provided with a buckle to clamp the upper pipe of the crucible at a preset position.

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