JP4945474B2 - Organic EL panel repair device and repair method - Google Patents

Description

  The present invention relates to a repair device and a repair method for a flexible organic EL panel.

  In recent years, attention has been paid to the practical use of organic EL panels. Unlike the liquid crystal panel, the organic EL panel can be configured flexibly.

  A flexible organic EL panel 20 shown in FIG. 4 includes a light transmissive first film 22, a light transmissive second film 24 facing the first film 22, and between the first film 22 and the second film 24. And the organic EL element 26 formed in the above. The organic EL element 26 is laminated on the first film 22. In order to seal the organic EL element 26, the peripheral edges of the films 22 and 24 are bonded together with an adhesive 28. The 2nd film 24 and the organic EL element 26 are adhere | attached with an adhesive agent as needed. In FIG. 4, there is one organic EL element 26, but actually a large number of organic EL elements 26 are arranged vertically and horizontally.

  The organic EL element 26 has a structure in which a transparent electrode 30, an organic layer 32, and a metal electrode 34 are laminated in this order from the first film side. The transparent electrode 30 is ITO or the like, and the metal electrode 34 is Al or the like. The transparent electrode 30 becomes an anode and the metal electrode 34 becomes a cathode. In FIG. 4, the organic layer 32 is a single layer, but a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are stacked in order from the anode side may be used. In the light-emitting layer, electrons and holes are recombined, so that light is emitted when the electrons change from the ground state to the excited state and further return to the ground state.

  Since the films 22 and 24 and the organic EL element 26 are flexible, the organic EL panel 20 becomes flexible. Unlike a liquid crystal panel, it can be arbitrarily curved and used.

  There is an organic EL panel 60 using a hard glass substrate 62 and a cap 64 instead of the films 22 and 24 (FIG. 5). The organic EL panel 60 cannot be arbitrarily curved like the liquid crystal panel. The glass substrate 62 has a thickness of about 700 μm, and the films 22 and 24 have a thickness of about 100 μm. The flexible organic EL panel 20 is considerably thinner.

  The organic EL panel 20 has a large number of organic EL elements 26 arranged vertically and horizontally, and it is quite difficult to manufacture all the organic EL elements 26 without defects. For example, the organic EL panel 20 is manufactured in a clean room, but there are cases where the electrodes are short-circuited or reduced in resistance due to dust generated in the manufacturing apparatus. The current leaks at the defective portion 36 and becomes a bright spot, degrading the display quality.

  Therefore, it is common to detect defects during the manufacturing process of the organic EL panel 20 and repair them. For example, a defect is detected from the first film side, and the laser beam L3 is irradiated to the defect portion 36. The metal electrode 34 at the defective portion 36 is evaporated by the laser L3, and the defective portion 36 is increased in resistance. Due to the repair, the defective portion 36 does not emit light, and it becomes difficult for the user to recognize the defective portion 36.

  As shown in FIG. 6, it is assumed that the amount of heat for evaporating the metal electrode 34 is Q1. During repair, the organic layer 32 is given a heat quantity Q4 that is much higher than the heat quantity Q1. This is because (1) it is necessary to increase the output of the laser L3 in consideration of the amount of heat absorbed by the organic layer 32 in addition to the amount of heat given to the metal electrode 34, and (2) the laser L3 passes through the organic layer 32. This is because the amount of heat applied to the metal electrode 34 is larger in the organic layer 32.

  In addition, since the flexible organic EL panel 20 is very thin, and there is little material for releasing heat like the glass substrate 62, a large amount of heat is also conducted around the defect portion 36. Specifically, in the case of the organic EL panel 60 of FIG. 5, heat conduction as indicated by an arrow Td occurs in the glass substrate 62, but the heat conduction of the flexible organic EL panel 20 is only in the direction of the arrow Tc. (FIG. 4). The organic EL element 26 around the defective portion 36 may be damaged by heat. The non-light emitting area is widened by repair, and the display quality is lowered.

  Repair cannot be performed if the output of the laser L3 is reduced so that heat is not transmitted to the periphery of the defective portion.

  If the laser L3 is irradiated from the metal electrode side, the organic layer 32 is not irradiated with the laser L3. It is considered that the amount of heat given to the organic layer 32 is small, and damage to the organic layer 32 can be reduced. However, the metal electrode 34 is opaque and the defective portion 36 cannot be recognized. Therefore, laser irradiation from the metal electrode side is not performed.

  If the coordinates of the defective portion 36 are known and an alignment mark is provided at the corner of the organic EL panel 20, the laser irradiation device 52 is automatically moved to the defective portion 36 by computer control, and the laser L3 is irradiated from the metal electrode side. It can be thought of as possible. However, the organic EL element 26 is very fine, and the final laser irradiation position is visually confirmed, and the laser irradiation position is finely adjusted as necessary. Automatic laser irradiation from the metal electrode side is likely to fail because fine adjustment is not possible.

  Patent Document 1 discloses a repair method using a laser. However, the cited document 1 is a repair of an array substrate for a liquid crystal panel, not an organic EL panel. Cited Document 1 irradiates a laser from the transparent electrode side, and if it is simply applied to an organic EL panel, it also damages the periphery of the defect. Cited Document 1 is repairing an array substrate, and sealing is not performed. Since the organic EL element is deteriorated by oxygen or moisture, in order to perform repair by the method of the cited document 1, it must be performed in an inert gas atmosphere, which is very difficult.

  Patent Document 2 discloses a method of forming an organic layer again after removing a defective portion with a laser. Cited Document 2 irradiates a laser having a wavelength specialized for cutting a molecular chain of an organic layer. However, in order to improve the light emission efficiency, the organic layer is generally a plurality of layers, and it is a problem whether all the plurality of layers made of different materials can be removed by the method of Patent Document 2. This point is not disclosed in Patent Document 2. In order to confirm the light emission of the organic layer, it is necessary to sandwich the organic layer between the two electrodes. However, according to the method of Cited Document 2, the upper electrode cannot be formed, and the light emission cannot be confirmed.

  Patent Document 3 discloses an organic EL panel repair device. However, it is an apparatus for an organic EL panel using a glass substrate, and is not a repair apparatus for a flexible organic EL panel. Note that Patent Document 4 is an apparatus that performs an inspection without damaging the organic EL panel, and does not relate to a repair after the inspection.

JP 2000-347217 A JP 2004-119243 A JP 2007-42498 A JP 2005-83951 A

  The objective of this invention is providing the repair apparatus and repair method which made the damage to the circumference | surroundings of a defective part as small as possible with respect to a flexible organic electroluminescent panel.

  As described above, the organic EL panel has an organic EL element between the light transmissive first film and the second film. In the organic EL element, a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side. In order to seal the organic EL element, the peripheral portions of the first film and the second film are bonded with an adhesive.

  An organic EL panel repair device uses a laser for repairing a defective portion of an organic EL panel, and includes a laser irradiation device that emits the laser. The laser irradiation apparatus irradiates the defect portion with the first laser from the first film side, and then irradiates the defect portion with the second laser from the second film side. The first laser has an output for forming a concave shape on the metal electrode, and the second laser has an output for evaporating the metal electrode.

  In the repair method using the above repair device, (1) the first laser is irradiated to the defective portion from the first film side, and (2) the second laser is irradiated to the defective portion from the second film side. . The metal electrode is marked by the above (1), and the metal electrode is evaporated by the above (2). Before (2) above, the laser irradiation position is adjusted to the concave shape formed by the marking.

  According to the present invention, the laser is irradiated in two steps, the organic layer can be cooled before the first to the second laser irradiation, and the temperature rise of the organic layer can be suppressed. Although the defective part cannot be recognized from the metal electrode side, the defective part can be recognized from the metal electrode side because the metal electrode at the defective part is deformed by the first laser irradiation. Since the second laser irradiation is performed from the metal electrode side, the organic layer is not irradiated with the laser. Therefore, the temperature rise of the organic layer can be suppressed, and the expansion of the defective portion can be prevented.

  Embodiments of the present invention will be described with reference to the drawings. The flexible organic EL panel to be repaired is the same as the organic EL panel described in the related art, and the description of the organic EL panel is omitted.

  As shown in FIG. 1, the repair device 10 includes a laser irradiation device 12. As the laser irradiation device 12, various laser irradiation devices such as YAG, excimer, semiconductor, and gas can be used. The wavelengths of the lasers L1 and L2 are about 200 to 1100 nm.

  The laser irradiation device 12 irradiates the defect portion 36 with the first laser L1 from the first film side (FIG. 1A), and then irradiates the defect portion 36 with the second laser L2 from the second film side. (FIG. 1B). In the present invention, the repair is not completed by one laser irradiation, but the laser irradiation is performed twice. The organic layer 32 can be cooled between the first laser irradiation and the second laser irradiation, and damage due to heat can be prevented.

The first laser L <b> 1 is an output for marking the metal electrode 34. As shown in FIG. 2, the mark formed by the marking has a concave shape 38. The second laser L2 has an output for evaporating the metal electrode. In the first laser irradiation, only the concave shape 38 is formed on the metal electrode 34, and the temperature rise of the organic layer 32 is small. The second laser irradiation evaporates the metal electrode 34, but the laser L2 is irradiated from the metal electrode side, so the temperature rise of the organic layer 32 is small. As an example of a specific output, the output of the laser L1 is about 5 × 10 ⁻⁵ to 4 × 10 ⁻⁵ mJ, and the output of the laser L2 is about 2 × 10 ⁻³ to 4 × 10 ⁻² mJ. .

  The concave shape 38 formed in the metal electrode 34 is a concave shape when viewed from the first film side. When viewed from the second film side, it has a convex shape. As described above, when the organic EL element 26 is viewed from the second film side, the metal electrode 34 is present, and the defective portion 36 cannot be confirmed. In the present invention, the concave shape 38 is formed in the metal electrode 34 by the first laser irradiation, and the concave shape 38 becomes a mark for determining the irradiation position at the second laser irradiation.

  In addition, the repair device 10 is a holder for the organic EL panel 20, a means for supporting the laser irradiation device 12 and moving the laser irradiation device 12 above the defective portion, a means for enlarging and displaying the defective portion 36, and an operation of the repair device 10. Including a computer for controlling. After the laser irradiation apparatus 12 is moved to the vicinity of the defect portion 36 by computer control, the defect portion 36 is enlarged and displayed, and the laser irradiation position is finely adjusted while visually observing. The holding table may include means for automatically inverting the organic EL panel 20. In addition, the repair device 10 includes means for lighting the organic EL panel 20. In order to adjust the irradiation positions of the lasers L1 and L2, the organic EL panel 20 is turned on so that the defective portion 36 can be identified.

  Although it is necessary to detect the defective part 36 before repairing, the detection method of the defective part 36 is not particularly limited in the present invention. For example, you may use the method disclosed by patent document 4 etc. which were shown by the prior art.

  A repair method using the repair device 10 will be described. In the repair method, (1) the first laser L1 is irradiated to the defective portion 36 from the first film side, and (2) the second laser L2 is irradiated to the defective portion 36 from the second film side. Unlike the conventional case, repair is not completed with a single laser irradiation.

  The first laser irradiation is a marking for the metal electrode 34, and a concave shape 38 is formed in the metal electrode 34. The metal electrode 34 at the defect portion 36 is evaporated by the second laser irradiation. The leak current at the defective portion 36 is eliminated, and the bright spot becomes a dark spot.

  3A and 3B show changes in the amount of heat by the first and second laser irradiations. In the first laser irradiation, the metal electrode 34 is given a heat quantity higher than the heat quantity Q1, but it is smaller than the conventional one and the time is also short. Therefore, the maximum amount of heat Q2 given to the organic layer 32 is also smaller than the conventional amount of heat Q4 and is a short time. Heat conduction to the periphery of the defect portion 36 can be reduced.

  In FIG. 3A, the amount of heat applied to the metal electrode 34 is larger than Q1, but the metal electrode 34 is not evaporated. FIG. 3A is due to consideration of heat conduction to the surroundings, and actually only the concave shape 38 is formed in the metal electrode 34.

  In the second laser irradiation, the metal electrode 34 is given a heat quantity Q1 to be evaporated or a heat quantity higher than the heat quantity Q1. However, the laser L2 is irradiated from the metal electrode side, and the laser L2 is not irradiated to the organic layer 32. The organic layer 32 only conducts heat indirectly from the metal electrode 34, and the maximum amount of heat Q3 given to the organic layer 32 is very small. Therefore, as indicated by arrows Ta and Tb in FIG. 1, the heat conducted to the periphery of the defective portion 36 is smaller than that in the prior art (arrow Tc in FIG. 4). Note that if the laser L2 is continuously irradiated even after the metal electrode 34 is evaporated, the laser L2 is directly irradiated to the organic layer 32. Therefore, the irradiation of the laser L2 is stopped immediately after the evaporation of the metal electrode 34.

  In FIG. 3B, the metal electrode 34 is given a heat quantity higher than the heat quantity Q1 for evaporation. This takes into account the heat that escapes to the surroundings by heat conduction during laser irradiation.

  Before the second laser irradiation, the irradiation position of the laser L2 is adjusted to the concave shape 38. By the first laser irradiation, the metal electrode 34 at the defective portion 36 is recessed, and the defective portion 36 can be recognized even from the second film side. The irradiation position of the laser L2 can be adjusted using the concave shape 38 as a mark.

  As described above, the present invention performs laser irradiation from the metal electrode side, which has not been conventionally performed. By irradiating the laser L2 from the metal electrode side, damage to the organic layer 32 due to heat can be minimized. Although the organic layer 32 is irradiated with the laser L1 before the metal electrode 34 is evaporated, the output of the laser L1 is small and damage to the organic layer 32 due to heat is suppressed as much as possible.

  Although the embodiment of the present invention has been described, the present invention is not limited to the above embodiment. For example, a dedicated laser irradiation device 12 for the lasers L1 and L2 may be provided. That is, there are two laser irradiation devices 12.

  The laser irradiation device 12 may be provided on both film sides of the organic EL panel 20. The lasers L1 and L2 can be irradiated from both sides without inverting the organic EL panel 20. In this case, the organic EL panel 20 is held in the vertical direction with respect to the horizontal. If the laser L2 is irradiated after the temperature of the organic layer 32 that has been raised by the laser L1 is lowered, damage to the organic layer 32 can be suppressed.

  The number of the laser irradiation devices 12 may be one, or the laser irradiation device 12 may be moved from the first film side to the second film side.

  When repairing a plurality of defects, the order of defects irradiated with the laser L1 and the order of defects irradiated with the laser L2 may be the same or different. The computer stores the order of the coordinates of the location to be repaired in the computer that controls the repair device 10, and the laser irradiation device 12 moves according to the order of the coordinates.

  Although the anode is a transparent electrode and the cathode is a metal electrode, the present invention can be applied even when the anode is a metal electrode and the cathode is a transparent electrode. After irradiating the laser from the transparent electrode side, the laser is irradiated from the metal electrode side to evaporate the metal electrode.

  For convenience of explanation, the film on the transparent electrode side is the first film and the film on the metal electrode side is the second film, but the positions of the first fill and the second film may be interchanged.

  Although the means for inverting the organic EL panel 20 is provided on the holding table, the organic EL panel 20 may be inverted by an operator who performs repair.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

It is a figure which shows the repair method using a repair apparatus, (a) is laser irradiation from the 1st film side, (b) is laser irradiation from the 2nd film side. It is a figure which shows a mode that the recessed part was formed. It is a figure which shows the change of the calorie | heat amount to the metal electrode and organic layer at the time of repair, (a) is a temperature change when laser irradiation is performed from the 1st film side, (b) is a laser from the 2nd film side. It is a temperature change at the time of irradiation. It is a figure which shows the repair method with respect to the conventional flexible organic electroluminescent panel. It is a figure which shows the repair method with respect to the organic electroluminescent panel using the conventional glass substrate. It is a figure which shows the change of the calorie | heat amount to the metal electrode and organic layer at the time of the conventional repair.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10, 50: Repair apparatus 12, 52: Laser irradiation apparatus 20: Organic EL panel 22, 24: Film 26: Organic EL element 28: Adhesive 30: Transparent electrode 32: Organic layer 34: Metal electrode 36: Defect location 38: Concave

Claims (5)

A light transmissive first film;
A light transmissive second film facing the first film;
An organic EL element formed between the first film and the second film, in which a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side;
A repair device for an organic EL device that repairs a defective portion of an organic EL panel including
A laser irradiation device for irradiating the defective portion with a laser, the laser irradiation device irradiating the defective portion with a first laser from the first film side, and then the second time from the second film side to the defective portion; Repair device that irradiates a laser. The repair device according to claim 1, wherein the first laser has an output for forming a concave shape on the metal electrode, and the second laser has an output for evaporating the metal electrode. A light transmissive first film;
A light transmissive second film facing the first film;
An organic EL element formed between the first film and the second film, in which a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side;
A repair method of an organic EL device that repairs a defective portion of an organic EL panel including a laser with a laser,
Irradiating a defect spot from the first film side to the first laser;
Irradiating a second portion of the laser on the defect from the second film side;
Including repair method. The repair method according to claim 3, wherein a mark is formed on the metal electrode by the first laser irradiation step, and the metal electrode is evaporated by the second laser irradiation step. The repair method according to claim 4, wherein the mark has a concave shape, and includes a step of adjusting a laser irradiation position to a concave shape before the second laser irradiation step.

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