CN114203782A

CN114203782A - OLED display panel and repair method thereof

Info

Publication number: CN114203782A
Application number: CN202111482250.XA
Authority: CN
Inventors: 袁松
Original assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Current assignee: Shenzhen China Star Optoelectronics Semiconductor Display Technology Co Ltd
Priority date: 2021-12-07
Filing date: 2021-12-07
Publication date: 2022-03-18

Abstract

The application provides an OLED display panel and a repairing method thereof. The OLED display panel comprises a TFT array substrate, a pixel definition layer, a plurality of organic material functional layers and a first electrode layer. The pixel definition layer is arranged on the TFT array substrate and is provided with a plurality of pixel definition areas. The plurality of organic material functional layers are respectively arranged in the plurality of pixel defining areas. The first electrode layer comprises a plurality of cathodes respectively covering the plurality of organic material functional layers and a plurality of cathode lap joint wires respectively connected with the plurality of cathodes. If one sub-pixel is an abnormal sub-pixel, the cathodes of the abnormal sub-pixels can be disconnected with the adjacent cathodes by disconnecting the plurality of cathode lapping wires connected with the cathodes of the abnormal sub-pixels, so that the abnormal sub-pixel dark spot repair is realized, in addition, only the cathode lapping wires need to be disconnected by laser in the repair process, the laser energy is lower, the cutting area is small, the damage to the sub-pixels around the abnormal sub-pixels can be reduced, and a large amount of abnormal particles can not be introduced.

Description

OLED display panel and repair method thereof

Technical Field

The application relates to the technical field of display devices, in particular to an OLED display panel and a repairing method thereof.

Background

The electroluminescent diode (OLED) has the advantages of simple manufacturing process, low cost, high light emitting efficiency, easy formation of flexible structure, low power consumption, high color saturation, wide viewing angle, and the like, and the display technology using the electroluminescent diode has become an important display technology.

OLEDs are current-mode light emitting devices that mainly include an anode, a cathode, and an organic material functional layer. The main working principle of the OLED is: the organic material functional layer emits light by carrier injection and recombination under the drive of an electric field formed by the anode and the cathode.

In the manufacturing process of the OLED display panel, there are some process defects that cause bright spots of sub-pixels, for example, abnormal particles (particles) exist on a TFT (thin film transistor) array substrate to cause short-circuiting or anode short-circuiting, and the like. In the prior art, the method for repairing the bright spot caused by the process defects mainly includes cutting the sub-pixel generating the bright spot by laser, for example, damaging the cathode and the organic material functional layer of the sub-pixel by laser, or performing circular cutting on the whole sub-pixel by laser to make the whole sub-pixel unable to normally emit light and become a dark spot. However, in the prior art, the sub-pixels of the bright spots are generated by laser cutting, the operation is complex, the cutting area is large, the laser energy is high, the surrounding sub-pixels are damaged, and a large amount of abnormal particles are easily introduced.

Disclosure of Invention

The application provides an OLED display panel and a repairing method thereof, which aim to solve the problems that in the prior art, the sub-pixels generating bright spots through laser cutting can damage the surrounding sub-pixels and a large amount of abnormal particles are easily introduced.

In one aspect, the present application provides an OLED display panel, including:

a TFT array substrate;

the pixel definition layer is arranged on the TFT array substrate and is provided with a plurality of pixel definition areas;

a plurality of organic material functional layers respectively disposed in the plurality of pixel defining regions;

the first electrode layer comprises a plurality of cathodes respectively covering the plurality of organic material functional layers and a plurality of cathode lap joint wires respectively connected with the plurality of cathodes; the cathode lap joint routing is used for disconnecting one cathode from a plurality of cathodes adjacent to the cathode after the cathode lap joint routing is disconnected.

In some possible implementations, each of the cathode overlapping traces connects two adjacent cathodes.

In some possible implementations, there is one cathode overlapping trace between two adjacent cathodes.

In some possible implementations, the cathode landing trace is directly above the pixel defining layer.

In some possible implementations, the organic material functional layer includes an electron transport layer between the cathode and the TFT array substrate, and between the cathode landing trace and the pixel defining layer.

In some possible implementations, the size of the cathode landing trace is smaller than the size of the cathode.

In some possible implementations, the cathode landing trace has a cross-sectional shape of a long strip.

In some possible implementations, the OLED display panel further includes an encapsulation layer disposed on the TFT array substrate and the first electrode layer.

In some possible implementations, the OLED display panel further includes a planarization layer disposed on the TFT array substrate, and the pixel defining layer is disposed on the planarization layer;

a second electrode layer comprising a plurality of anodes disposed on the planarization layer and respectively located below the plurality of organic material functional layers.

In another aspect, the present application further provides a repair method for an OLED display panel, including:

providing the OLED display panel;

detecting the OLED display panel to determine abnormal sub-pixels;

and irradiating at least one cathode lapping wire connected with the cathode in the abnormal sub-pixel by adopting laser to disconnect the cathode lapping wire so as to disconnect the cathode in the abnormal sub-pixel from a plurality of adjacent cathodes.

The OLED display panel comprises a TFT array substrate, a pixel definition layer, a plurality of organic material functional layers and a first electrode layer. The pixel definition layer is arranged on the TFT array substrate and is provided with a plurality of pixel definition areas. The plurality of organic material functional layers are respectively arranged in the plurality of pixel defining areas. The first electrode layer comprises a plurality of cathodes respectively covering the plurality of organic material functional layers and a plurality of cathode lap joint wires respectively connected with the plurality of cathodes. The cathode lap trace is used for disconnecting one cathode from a plurality of cathodes adjacent to the cathode lap trace after the cathode lap trace is disconnected. The method comprises the steps that an anode and an organic material functional layer correspond to a sub-pixel, if the sub-pixel is an abnormal sub-pixel, a plurality of cathode lapping wires connected with a cathode of the abnormal sub-pixel are disconnected, the cathode of the abnormal sub-pixel is disconnected with a plurality of adjacent cathodes, the abnormal sub-pixel is changed into a dark spot, the abnormal sub-pixel is repaired in a dark spot mode, in addition, only the cathode lapping wires are disconnected through laser in the repairing process, compared with the prior art that the cathode and the organic material functional layer of the sub-pixel are damaged through laser, or the whole sub-pixel is subjected to circular cutting through the laser, the laser energy adopted in the repairing process is lower, the cutting area is small, the damage to the sub-pixel around the abnormal sub-pixel can be reduced, and a large number of abnormal particles cannot be introduced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic diagram of an OLED display panel according to an embodiment of the present application;

FIG. 2 is a schematic diagram of a sub-pixel of an OLED display panel according to an embodiment of the present disclosure;

fig. 3 and 4 are schematic diagrams illustrating a repair method for an OLED display panel according to an embodiment of the present disclosure;

fig. 5 is a flowchart of a repair method for an OLED display panel according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. It is to be understood that the embodiments described are only a few embodiments of the present application and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

In the description of the present application, it is to be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the present application and for simplicity in description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed in a particular orientation, and be operated in a particular manner, and are not to be construed as limiting the present application. Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present application, "a plurality" means two or more unless specifically limited otherwise.

In the description of the present application, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; may be mechanically connected, may be electrically connected or may be in communication with each other; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art as appropriate.

In this application, unless expressly stated or limited otherwise, the first feature "on" or "under" the second feature may comprise direct contact of the first and second features, or may comprise contact of the first and second features not directly but through another feature in between. Also, the first feature being "on," "above" and "over" the second feature includes the first feature being directly on and obliquely above the second feature, or merely indicating that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature includes the first feature being directly under and obliquely below the second feature, or simply meaning that the first feature is at a lesser elevation than the second feature.

The following disclosure provides many different embodiments or examples for implementing different features of the application. In order to simplify the disclosure of the present application, specific example components and arrangements are described below. Of course, they are merely examples and are not intended to limit the present application. Moreover, the present application may repeat reference numerals and/or reference letters in the various examples, which have been repeated for purposes of brevity and clarity and do not in themselves dictate a relationship between the various embodiments and/or arrangements discussed. In addition, examples of various specific processes and materials are provided herein, but one of ordinary skill in the art may recognize applications of other processes and/or use of other materials.

Referring to fig. 1 to 5, an embodiment of the present invention provides an OLED display panel, including:

a TFT array substrate 1;

a pixel defining layer 2, the pixel defining layer 2 is arranged on the TFT array substrate 1, and the pixel defining layer 2 is provided with a plurality of pixel defining areas 21;

a plurality of organic material functional layers 3, the plurality of organic material functional layers 3 being respectively provided in the plurality of pixel defining regions 21;

a first electrode layer 4, wherein the first electrode layer 4 comprises a plurality of cathodes 41 respectively covering the plurality of organic material functional layers 3, and a plurality of cathode lap joint wires 42 respectively connected with the plurality of cathodes 41; the cathode tap wire 42 is used to disconnect one cathode 41 from its adjacent cathodes 41 after being disconnected.

It should be noted that the pixel defining region 21 refers to a region where the sub-pixels 100 are formed, the plurality of pixel defining regions 21 correspond to the plurality of sub-pixels 100, respectively, and one anode 61 and one organic material functional layer 3 correspond to one sub-pixel 100. The cathode 41 of the prior art generally covers the whole surface of the TFT array substrate 1, the pixel defining layer 2 and the plurality of organic material functional layers 3, so the prior art destroys the cathode 41 and the organic material functional layers 3 of the sub-pixel 100 by laser, or cuts the whole sub-pixel 100 by laser (i.e. cuts one circle around the sub-pixel 100) to repair the dark spot of the abnormal sub-pixel 200. The first electrode layer 4 of the present application includes a plurality of cathodes 41 and a plurality of cathode overlapping traces 42, which is equivalent to performing patterning processing on the cathodes 41 covered on the whole surface in the prior art to form a plurality of cathode overlapping traces 42, if one sub-pixel 100 is an abnormal sub-pixel 200, the plurality of cathode overlapping traces 42 connected to the cathodes 41 of the abnormal sub-pixel 200 may be disconnected, for example, the cathode overlapping traces 42 are irradiated by laser to fuse the cathodes 41 of the abnormal sub-pixel 200, so that the cathodes 41 of the abnormal sub-pixel 200 are disconnected from the adjacent plurality of cathodes 41, the cathodes 41 of the abnormal sub-pixel 200 cannot be connected to a low voltage, and the abnormal sub-pixel 200 cannot emit light, so that the abnormal sub-pixel 200 becomes a dark spot, and the abnormal sub-pixel 200 is repaired by dark spot, and only the cathode overlapping traces 42 need to be disconnected by laser in the repairing process, compared with the prior art that the cathodes 41 of the sub-pixel 100 and the organic material functional layer 3 are damaged by laser, or, the whole sub-pixel 100 is ring-cut by laser, the laser energy adopted in the repair process is lower, the cutting area is small (i.e. ring-cut is not needed), the damage to the sub-pixel 100 around the abnormal sub-pixel 200 can be reduced, and a large amount of abnormal particles are not introduced.

In addition, since the abnormal sub-pixel 200 is repaired by the hidden point repair of the fused cathode overlapping trace 42, the hidden point repair of the abnormal sub-pixel 200 can be realized no matter the defect in the TFT array substrate 1 or the abnormal sub-pixel 200 caused by other process defects. In addition, the abnormal sub-pixel 200 may be a bright dot abnormal sub-pixel, a mixed color dot abnormal sub-pixel, or a color dot abnormal sub-pixel.

The application of the OLED display panel is not specifically limited, and the OLED display panel may be any product or component with a display function, such as a television, a notebook computer, a tablet computer, a wearable display device (e.g., a smart band, a smart watch, and the like), a mobile phone, a virtual reality device, an augmented reality device, a vehicle-mounted display, an advertising light box, and the like.

In some embodiments, the TFT array substrate 1 includes an active layer, a first metal layer, a second metal layer, and an interlayer dielectric layer formed therebetween. The first metal layer may include a gate, and the second metal layer may include a source and a drain connected to the gate.

In some embodiments, the first electrode layer 4 may be patterned by using a Fine Metal Mask (FMM) to form a plurality of cathodes 41 and a plurality of cathode landing traces 42.

In some embodiments, referring to fig. 1, the OLED display panel further includes a planarization layer 5, the planarization layer 5 is disposed on the TFT array substrate 1, and the pixel defining layer 2 is disposed on the planarization layer 5. A second electrode layer 6, wherein the second electrode layer 6 comprises a plurality of anodes 61 arranged on the flat layer 5 and respectively positioned below the plurality of organic material functional layers 3. The anode 61 can be connected with the drain electrode of the TFT array substrate 1, the pixel definition layer 2, the anode 61 and the organic material function layer 3 can be flatly arranged by arranging the flat layer 5, the light emitting uniformity is improved, and the cathode lapping wiring 42 can be flatly arranged, so that the cathode lapping wiring 42 is conveniently fused by laser in the shading repair process of the abnormal sub-pixel 200, and the repair success rate is improved.

In some embodiments, referring to fig. 2 and 4, each cathode landing trace 42 connects two adjacent cathodes 41. That is, each cathode overlapping trace 42 is located between two adjacent cathodes 41, so that the positions of the cathode overlapping traces 42 are determined, which is beneficial to fusing the cathode overlapping traces 42 by laser in the subsequent shading repair process of the abnormal sub-pixel 200, and the repair success rate is improved.

In this embodiment, referring to fig. 2 and fig. 4, a cathode overlapping trace 42 is disposed between two adjacent cathodes 41. Not only can one cathode 41 be connected with a plurality of cathodes 41 adjacent to the cathode 41 to reduce the resistance of the cathode 41 and improve the electrical performance, but also the number of cathode overlapping wires 42 connected with one cathode 41 can be minimized, so that the number of the cathode overlapping wires 42 fused by laser can be minimized in the subsequent shading repair process of the abnormal sub-pixel 200, the cutting area can be reduced, the damage to the sub-pixels 100 around the abnormal sub-pixel 200 can be reduced, a large number of abnormal particles can not be introduced, and the repair efficiency and the repair success rate can be improved.

For example, when the plurality of sub-pixels 100 are arranged in an array, in one circle of sub-pixels 100 at the outermost periphery, the sub-pixels 100 at four corners are adjacent to only two sub-pixels 100, and the cathodes 41 in the sub-pixels 100 at four corners are connected to only two cathode landing traces 42. In the outermost sub-pixel 100, the sub-pixels 100 not located at four corners are only adjacent to three sub-pixels 100, and the cathodes 41 in the sub-pixels 100 not located at four corners in the outermost sub-pixel 100 are only connected to three cathode bridging wires 42. Except for the outermost circle of sub-pixels 100, the sub-pixels 100 at other positions are all adjacent to the four sub-pixels 100 (i.e. there is one sub-pixel 100 at each of the upper, lower, left and right sides), and then the cathode 41 in one sub-pixel 100 is connected to the four cathode bridging wires 42.

In some embodiments, referring to fig. 1 and fig. 3, the cathode landing trace 42 is located right above the pixel defining layer 2. That is, the orthographic projection of the cathode overlapping trace 42 on the TFT array substrate 1 is located in the orthographic projection of the pixel definition layer 2 on the TFT array substrate 1, and in the process of repairing the abnormal sub-pixel 200 by darkening, after the cathode overlapping trace 42 is fused by laser, the laser irradiates the pixel definition layer 2, thereby avoiding affecting other sub-pixels 100.

In this embodiment, the organic material functional layer 3 includes an electron transport layer 31 between the cathode 41 and the TFT array substrate 1, and between the cathode landing trace 42 and the pixel defining layer 2. That is to say, the electron transport layer 31 in the prior art is only located between the cathode 41 and the TFT array substrate 1, and the electron transport layer 31 is further disposed between the cathode overlapping trace 42 and the pixel defining layer 2, in the process of repairing the abnormal sub-pixel 200 by darkening, after the cathode overlapping trace 42 is fused by laser, the laser irradiates the electron transport layer 31 of the abnormal sub-pixel 200, and the influence on the other sub-pixels 100 is avoided.

In addition, the organic material functional layer 3 further includes a light emitting layer 32 disposed below the electron transport layer 31, a hole transport layer 33 disposed below the light emitting layer 32, and a hole injection layer 34 disposed below the hole transport layer 33.

In some embodiments, the size of the cathode overlapping trace 42 is smaller than that of the cathode 41, so that when the cathode overlapping trace 42 is fused by laser in the subsequent shading repair process of the abnormal sub-pixel 200, the moving distance of the laser is reduced, even the laser does not need to move (for example, the width of the cathode overlapping trace 42 is smaller than or equal to the diameter of the laser), the cutting area is further reduced, the damage to the sub-pixels 100 around the abnormal sub-pixel 200 is further reduced, a large number of abnormal particles are not introduced, and the repair efficiency and the repair success rate are improved.

In some embodiments, the cross-sectional shape of the cathode overlapping trace 42 is a long strip (for example, a rectangle with a width much smaller than a length), and the width of the cathode overlapping trace 42 is reduced, so that in the subsequent shading repair process of the abnormal sub-pixel 200, when the cathode overlapping trace 42 is fused by laser, the moving distance of the laser is reduced, even the laser does not need to move, the cutting area is further reduced, the damage to the sub-pixels 100 around the abnormal sub-pixel 200 is further reduced, a large number of abnormal particles are not introduced, and the repair efficiency and the repair success rate are improved.

In some embodiments, referring to fig. 1 and fig. 3, the OLED display panel further includes an encapsulation layer 7, and the encapsulation layer 7 is disposed on the TFT array substrate 1 and the first electrode layer 4. The packaging layer 7 improves the water and oxygen blocking capability of the OLED display panel, and the service life of the OLED display panel is prolonged. The shading repair for the abnormal sub-pixel 200 may be performed after the first electrode layer 4 is fabricated, or may be performed after the packaging process (i.e., the packaging layer 7 is fabricated).

In addition, the dark spot repair for the abnormal sub-pixel 200 can also be performed in a Cell (Cell) inspection process.

Referring to fig. 3 to fig. 5, based on the OLED display panel, an embodiment of the present invention further provides a method for repairing an OLED display panel, including:

step S1, providing the above OLED display panel;

step S2, detecting the OLED display panel to determine the abnormal sub-pixel 200;

step S3, irradiating at least one cathode overlapping trace 42 connected to the cathode 41 in the abnormal sub-pixel 200 with laser to disconnect the cathode overlapping trace 42, so as to disconnect the cathode 41 in the abnormal sub-pixel 200 from the plurality of cathodes 41 adjacent to the cathode 41.

In the foregoing embodiments, the descriptions of the respective embodiments have respective emphasis, and for parts that are not described in detail in a certain embodiment, reference may be made to related descriptions of other embodiments. In a specific implementation, each unit or structure may be implemented as an independent entity, or may be combined arbitrarily to be implemented as one or several entities, and the specific implementation of each unit or structure may refer to the foregoing method embodiment, which is not described herein again.

The OLED display panel and the repair method thereof provided in the embodiments of the present application are described in detail above, and specific examples are applied in the description to explain the principle and implementation manner of the embodiments of the present application, and the description of the embodiments above is only used to help understanding the technical solutions and core ideas of the embodiments of the present application; those of ordinary skill in the art will understand that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; such modifications or substitutions do not depart from the spirit and scope of the present disclosure as defined by the appended claims.

Claims

1. An OLED display panel, comprising:

a TFT array substrate;

2. The OLED display panel of claim 1, wherein each cathode landing trace connects two adjacent cathodes.

3. The OLED display panel of claim 2, wherein there is one cathode overlapping trace between two adjacent cathodes.

4. The OLED display panel of claim 1, wherein the cathode landing trace is directly over the pixel defining layer.

5. The OLED display panel of claim 4, wherein the functional layer of organic material comprises an electron transport layer between the cathode and the TFT array substrate and between the cathode landing traces and the pixel definition layer.

6. The OLED display panel of any one of claims 1 to 5, wherein the cathode landing trace has a size smaller than the size of the cathode.

7. The OLED display panel of any one of claims 1 to 5, wherein the cathode landing traces are elongated in cross-sectional shape.

8. The OLED display panel of any one of claims 1 to 5, further comprising an encapsulation layer disposed on the TFT array substrate and the first electrode layer.

9. The OLED display panel according to any one of claims 1 to 5, further comprising a planarization layer disposed on the TFT array substrate, the pixel defining layer being disposed on the planarization layer;

10. A repair method of an OLED display panel is characterized by comprising the following steps:

providing an OLED display panel according to any one of claims 1 to 9;

detecting the OLED display panel to determine abnormal sub-pixels;