Patent Application
20240147756
This application claims the benefit of Chinese Patent Application No. 202211358665.0, filed on Nov. 1, 2022. The entire disclosure of the above application is incorporated herein by reference.
The present disclosure relates to a technical field of display, and more particularly, to an OLED display panel and a preparation method for OLED display panel.
This section provides background information related to the present disclosure which is not necessarily prior art.
A cathode layer and an electron transport layer cover different area. When vaporing and depositing the cathode layer and the electron transport layer of OLED display panel, two vapor deposition masks are currently used as a solution for mass production, i.e., a vapor deposition technology called two masks for Cathode/ET.
At present, in some OLED display panel, the electron transport layer is provided on an entire surface. Due to a poor conductivity of the electron transport layer, a conduction between the cathode layer and a metal layer of an underlying array substrate is affected. Thus, it is difficult to form a good electrical connection between the cathode layer and the metal layer of the underlying array substrate.
Therefore, the conventional OLED display panel has a technical problem of low yield when the electron transport layer covers the auxiliary electrode.
Embodiments of the present disclosure provide an OLED display panel and a preparation method for OLED display panel, thereby alleviating a technical problem of low yield when an electron transport layer covers an auxiliary electrode in an OLED display panel.
Embodiments of the present disclosure provide an OLED display panel and a preparation method for OLED display panel, thereby alleviating a technical problem of low yield when an electron transport layer covers an auxiliary electrode in an OLED display panel.
An embodiment of the present disclosure provides an OLED display panel including:
In some embodiments of the present disclosure, the auxiliary electrode further comprises a first auxiliary electrode disposed in a non-display area and a second auxiliary electrode disposed in a display area, wherein the cathode layer is electrically connected to the second metal layer through the first auxiliary electrode in the non-display area, and the second auxiliary electrode is electrically connected to the cathode in parallel in the display area.
In some embodiments of the present disclosure, the first auxiliary electrode has at least one first scratching chamfer structure, and the second auxiliary electrode has at least one second scratching chamfer structure, wherein the first scratching chamfer structure contacts with the cathode layer, and the second scratching chamfer structure contacts with the cathode layer.
In some embodiments of the present disclosure, the first auxiliary electrode is provided in a grid shape or in a separated arc shape.
In some embodiments of the present disclosure, the first auxiliary electrode has a cross-section of trapezoidal shape, an angle is defined between at least one inclined side of the trapezoidal shape and the substrate, and the angle ranges from 75° to 90°.
In some embodiments of the present disclosure, the groove comprises a first groove and a second groove, the first auxiliary electrode is provided with the first groove, the second auxiliary electrode is provided with the second groove, wherein a depth of the first groove is less than or equal to a thickness of the first auxiliary electrode, and a depth of the second groove is less than or equal to a thickness of the second auxiliary electrode.
In some embodiments of the present disclosure, the electron transport layer has a thickness of 10 nm to 20 nm.
In some embodiments of the present disclosure, the anode layer is disposed in a three-layer stacked structure.
An embodiment of the present disclosure provides a preparation method for OLED display panel, including:
In some embodiments of the present disclosure, the preparing an electron transport layer and the cathode layer sequentially on a side of the anode layer away from the substrate further includes:
Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure.
In the overlapping area of the conventional OLED display panel, the electron transport layer covers the auxiliary electrode to separate the auxiliary electrode from the cathode layer, hence the auxiliary electrode and the cathode layer have a poor conduction therebetween. In the present disclosure, grooves are provided on a surface of the auxiliary electrode close to the cathode layer, and thus, the auxiliary electrode extends through the electron transport layer and contacts with the cathode layer. It improves the conduction between the cathode layer and the auxiliary electrode, and thereby alleviating the technical problem that the conventional OLED display panel has a low yield when the electron transport layer covers the auxiliary electrode.
In order that the technical solution in the embodiments of the present disclosure may be explained more clearly, reference will now be made briefly to the accompanying drawings required for the description of the embodiments. It will be apparent that the accompanying drawings in the following description are merely some of the embodiments of the present disclosure, and other drawings may be made to those skilled in the art without involving any inventive effort.
In the following, the technical solutions in the embodiments of the present disclosure will be clearly and completely described in connection with the accompanying drawings in the embodiments of the present disclosure. It will be apparent that the described embodiments are merely a part of the embodiments of the present disclosure, rather than all the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by a person skilled in the art without involving any inventive effort are within the scope of the present disclosure. Furthermore, it is to be understood that the specific embodiments described herein are for purposes of illustration and explanation only and are not intended to limit the disclosure. In the present disclosure, if not stated to the contrary, the use of positional terms such as “above” and “down” usually refer to above and down of a device in actual use or a work state, specifically referring to the direction of the drawings. The terms such as “in” and “out” are usually for the profile of the device.
In a conventional OLED display panel 1, particularly in an overlapping area of a non-display area 3, referring to
It should be understood that, as a vapor deposition technology called two masks for Cathode/ET, referring to
Referring to
Referring to
It should be understood that, in an area where the first auxiliary electrode 501 is provided with the groove 100, there is a boss structure defined between two adjacent grooves 100. There is a level difference between the top of the boss structure and the bottom of the groove 100. The boss structure has a taper angle, and the edge around the groove 100 (i.e. the edge of the top of the boss structure) is formed with a scratching chamfer, as shown by sign 120
As such, in the overlapping area 110, referring to
It should be understood that, referring to
In the present embodiment, referring to
In an embodiment, referring to
Herein, in the overlapping area 110 of the non-display area 3, the cathode layer 90 is electrically connected to the connecting electrode 201 through the first auxiliary electrode 501, so that the external signal can be transmitted to the display surface through the cathode layer 90.
The first auxiliary electrode 501 may serve as a transition electrode, wherein a side of the first auxiliary electrode 501 is connected to the cathode layer 90, and another side of the first auxiliary electrode 501 is connected to the connecting electrode 201. In an embodiment, the first auxiliary electrode 501 is continuously provided, and a side of the first auxiliary electrode 501 close to the substrate 10 is in surface contact with the connecting electrode 201.
In an embodiment, referring to
Further, the first auxiliary electrode 501 at least covers where abnormal connection such as the wire breakage of the cathode layer 90, and the first auxiliary electrode 501 is continuously provided in the via hole 130. Even if the cathode layer 90 is broken in the via hole 130 of the overlapping area 110, the cathode layer 90 can still be in a continuous surface contact with the connecting electrode 201 through the first auxiliary electrode 501, thereby achieving a good electrical connection.
In the present embodiment, a continuous first auxiliary electrode 501 is provided in the overlapping area 110 of the non-display area 3, so that the cathode layer 90 and the connecting electrode 201 are electrically connected through the first auxiliary electrode 501, thereby avoiding abnormal electrical connection caused by the wire breakage of the cathode layer.
In an embodiment, referring to
In an embodiment, the depth of the groove may be less than the thickness of the first auxiliary electrode 501. This is, the first auxiliary electrode 501 is provided continuously.
In an embodiment, the depth of the groove may be equal to the thickness of the first auxiliary electrode. This is, the first auxiliary electrode 501 is discontinued by the groove, and a hollow area is formed by the groove. The first auxiliary electrode 501 includes a plurality of hollow areas. In a grid shape, the hollow areas may be disposed in an array. In a separated arc shape, the hollow areas may be disposed between adjacent arc branches.
It should be understood that by hollowing out the groove in the first auxiliary electrode 501, the level difference can be further increased, and the probability of the first auxiliary electrode 501 extending through the electron transport layer 80 can be increased.
In the present embodiment, the probability that the first auxiliary electrode 501 extends through the electron transport layer 80 is further increased by defining the depth and the arrangement form of the groove in the first auxiliary electrode 501, thereby improving the conduction between the cathode layer 90 and the connecting electrode 201.
In an embodiment, the anode layer 50 is provided in a three-layer stacked structure, and the first auxiliary electrode 501 is also provided in a three-layer stacked structure.
Herein, the anode layer 50 may have a three-layer structure of titanium, silver, and indium tin oxide, wherein the titanium may be used as a hydrogen absorbing material to prevent hydrogen atoms from diffusing into the underlying TFT device, thereby improving the stability of the TFT device.
In an embodiment, referring to
It should be understood that the three-layer stacked structure has a large thickness and a steep side, thereby facilitating the first auxiliary electrode 501 extending through the electron transport layer 80 to contact with the cathode layer 90.
In the present embodiment, by providing the first auxiliary electrode 501 as a three-layer stacked structure, the probability of forming the first scratching chamfer is increased, thereby increasing the probability that the first auxiliary electrode 501 extends through the electron transport layer 80, and improving the conduction between the cathode layer 90 and the connecting electrode 201.
In an embodiment, referring to
Herein, the conduction between the cathode layer 90 and the connecting electrode 201 is improved by the first scratching chamfer 120 extending through the electron transport layer 80.
It should be understood that, when the first auxiliary electrode 501 is a three-layer stacked structure, it is possible to have more first scratching chamfers than a single-layer structure. By increasing the number of the first scratching chamfers 120, the cathode layer has more contacts with the first scratching chamfers 120. Due to more contacts between the cathode layer and the first scratching chamfers 120, the contact area between the first auxiliary electrode 501 and the cathode layer 90 can be increased, thereby reducing the impedance of the cathode layer 90.
In the present embodiment, the contact area between the first auxiliary electrode 501 and the cathode layer 90 is advantageously increased by a plurality of first scratching chamfers 120 formed at the edges around the three-layer stacked structure of the first auxiliary electrode 501. The impedance of the cathode layer 90 can be reduced based on the fact that the contact area is inversely proportional to the impedance.
In an embodiment, referring to
The first angle α is a taper angle of the boss structure of the first auxiliary electrode 501.
It should be understood that, when the first angle α defined between at least one inclined side of the trapezoidal shape and the substrate 10 ranges from 75° to 90°, the side of the trapezoidal shape is steeper, and the first auxiliary electrode 501 extends through the electron transport layer 80 to contact with the cathode layer 90.
Preferably, the first angle α may be 750 or 90°, wherein 750 and 900 are endpoints of the range of the first angle α. If the first angle α is less than 750 or greater than 90°, the side of the trapezoidal shape of the first auxiliary electrode 501 is not steep enough, and it is difficult for the first auxiliary electrode 501 to extend through the electron transport layer 80 and to contact with the cathode layer 90. Alternatively, the first angle α may be 80°.
In this embodiment, by specifically defining the trapezoidal shape of the first auxiliary electrode 501 and the taper angle α, the probability that the first auxiliary electrode 501 extends through the electron transport layer 80 is further increased.
In an embodiment, referring to
In the overlapping area 110 of the display area 2, the second auxiliary electrode 502 is electrically connected in parallel with the cathode layer 90 to reduce the impedance of the cathode layer 90, instead of serving as a transition electrode as the first auxiliary electrode 501. That is, the functions and usages of the first auxiliary electrode 501 and the second auxiliary electrode 502 are different, and the positions of the first auxiliary electrode 501 and the second auxiliary electrode 502 are different. The effect on overlapping the cathode layer 90 and the first auxiliary electrode 501 in the overlapping area 110 of the display area 2 is different from that the effect on overlapping the cathode layer 90 and the second auxiliary electrode 502 in the overlapping area 110 of the non-display area 3.
Referring to
In an embodiment, the groove comprises a first groove (referring to the groove 100 shown in
It should be understood that the second auxiliary electrode 502 is electrically connected in parallel with the cathode layer 90, and the impedance of the second auxiliary electrode 502 is relatively small. According to the calculation formula of the total impedance in parallel, the total impedance of the cathode in parallel connection is less than the total impedance of the second auxiliary electrode 502, thereby greatly reducing the impedance of the cathode layer 90, and alleviating a technical problem that a large signal loss is caused by a large voltage drop of the cathode layer 90.
It should be understood that the second auxiliary electrodes 502 may be arranged in an array in a plane. Specifically, the display area 2 may be divided into a plurality of impedance areas to be reduced, and each of the impedance areas to be reduced is provided with a second auxiliary electrode 502 electrically connected to the cathode layer 90. As such, the voltage drop of each segment of the cathode layer 90 is better reduced, and the voltage drop of each area in the plane is more uniform, thereby ensuring uniformity of brightness.
In the present embodiment, the second auxiliary electrode 502 is provided in the display area 2, and the second auxiliary electrode 502 is connected to the cathode layer 90, and thereby reducing the voltage drop of the cathode layer 90. It is prevented the display panel from being uneven in brightness due to large signal loss of the cathode layer 90.
In an embodiment, the second auxiliary electrode 502 is provided in a grid shape or in a separated arc shape, wherein the separated arc shape has a trunk and a plurality of arc branches extending from the trunk, and the arc branches are separated from each other. As similar example of first auxiliary electrode 501 shown in
In an embodiment, the depth of the second groove may be less than the thickness of the second auxiliary electrode 502. This is, the second auxiliary electrodes 502 is provided continuously.
In an embodiment, the depth of the second groove may be equal to the thickness of the second auxiliary electrode 502. This is, the second auxiliary electrode 502 is discontinued by the second groove, and a hollow area is formed by the second groove. The second auxiliary electrode 502 includes a plurality of hollow areas. In a grid shape, the hollow areas may be disposed in an array. In a separated arc shape, the hollow areas may be disposed between adjacent arc branches.
It should be understood by hollowing out the second groove in the second auxiliary electrode 502, the level difference can be further increased, and the probability of the second auxiliary electrode 502 extending through the electron transport layer 80 can be increased.
In the present embodiment, by defining the depth and the arrangement form of the second groove in the second auxiliary electrode 502, the probability that the second auxiliary electrode 502 extends through the electron transport layer 80 is further increased, thereby improving the conduction between the cathode layer 90 and the connecting electrode 201.
In an embodiment, the anode layer 50 is provided in a three-layer stacked structure, and the second auxiliary electrode 502 is also provided in a three-layer stacked structure.
Herein, the anode layer 50 may have a three-layer structure of titanium, silver, and indium tin oxide, wherein the titanium may be used as a hydrogen absorbing material to prevent hydrogen atoms from diffusing into the underlying TFT device, thereby improving the stability of the TFT device.
It should be understood that the second auxiliary electrode 502 is provided in a three-layer stacked structure, similar with the example of the first auxiliary electrode 501 as shown in
It should be understood that the three-layer stacked structure has a large thickness and a steep side, thereby facilitating the second auxiliary electrode 502 extending through the electron transport layer 80 to contact with the cathode layer 90.
In the present embodiment, by providing the second auxiliary electrode 502 as a three-layer stacked structure, the probability of forming the second scratching chamfer is increased, thereby increasing the probability that the second auxiliary electrode 502 extends through the electron transport layer 80, and improving the conduction between the cathode layer 90 and the connecting electrode 201.
In an embodiment, the three-layer stacked structure of the second auxiliary electrode 502 has at least one second scratching chamfer, wherein the second scratching chamfer contacts with the cathode layer 90. The second auxiliary electrodes 502 may include at least two second scratching chamfer, wherein at least one of the second scratching chamfer contacts with the cathode layer 90. Similar with the example of the first scratching chamfer 120 shown in
Herein, the conduction between the cathode layer 90 and the connecting electrode 201 is improved by the second scratching chamfer extending through the electron transport layer 80.
It should be understood, that the impedance of the cathode layer 90 can be reduced by increasing the number of the second scratching chamfers, and further by increasing the contact area between the second scratching chamfer and the cathode layer 90.
In the present embodiment, the contact area between the second auxiliary electrode 502 and the cathode layer 90 is advantageously increased by a plurality of second scratching chamfers formed at the edge around the three-layer stacked structure of the second auxiliary electrode 502. The impedance of the cathode layer 90 can be reduced based on the fact that the contact area is inversely proportional to the impedance.
In an embodiment, the second auxiliary electrode 502 has a cross-section of trapezoidal shape, wherein a second angle is defined between at least one inclined side of the trapezoidal shape and the substrate 10, and the second angle ranges from 750 to 90°.
It should be understood that, when the second angle defined between at least one inclined side of the second auxiliary electrode 502 and the substrate 10 ranges from 75° to 90°, the side of the second auxiliary electrode 502 is steeper, and the second auxiliary electrode 502 extends through the electron transport layer 80 to contact with the cathode layer 90. Alternatively, the second angle may be 75°, 80°, and 90°.
In the present embodiment, by specifically defining the shape of the second auxiliary electrode 502 and the taper angle, the probability that the second auxiliary electrode 502 extends through the electron transport layer 80 is further increased.
In an embodiment, the electron transport layer 80 has a thickness ranging from 10 nm to 20 nm.
Preferably, the electron transport layer 80 has a thickness of 10 nm. By reducing the thickness of the electron transport layer 80, it is convenient for the auxiliary electrode to extend through the electron transport layer 80, so that the auxiliary electrode contacts with the cathode layer 90 and is conductive. The thickness of the electron transport layer 80 may also be 15 nm or 20 nm, which is not specifically limited in the present disclosure.
In the present embodiment, the electron transport layer 80 has a thin thickness, which facilitates the auxiliary electrode to extend through the electron transport layer 80 and further to contact with the cathode layer 90, thereby increasing the yield of the OLED display panel 1.
Referring to
It should be understood that, when the electron transport layer 80 is prepared on the side of the anode layer 50 away from the substrate 10, the electron transport layer 80 is discontinuously provided, and the electron transport layer 80 is disconnected at the position where the auxiliary electrode is provided.
Further, the electron transport layer 80 has a thinner thickness, and the auxiliary electrode is prepared in the same layer as the anode layer 50. Since the anode layer 50 and the auxiliary electrode have a thicker thickness and easily form with a plurality of scratching chamfers, the auxiliary electrode easily extends through the electron transport layer 80 and contacts with the cathode layer 90.
In an embodiment, the step of preparing the anode layer 50 further includes: coating two layers of metal material and one layer of indium tin oxide material on a side of the second metal layer 20 away from the substrate 10, patterning the three layers to prepare the anode layer 50 having a three-layer stacked structure.
The two layers of the metal material may be a titanium layer provided close to the substrate 10 and a copper layer provided on a side of the titanium layer away from the substrate 10.
The present disclosure further provides a display module and a display device, wherein the display module and the display device each include the OLED display panel, and details are not described herein.
An OLED display panel according to the embodiment includes a substrate, a second metal layer, an anode layer, an electron transport layer, and a cathode layer, wherein the second metal layer is disposed on the substrate, the anode layer is disposed on a side of the second metal layer away from the substrate and includes an anode and an auxiliary electrode disposed in a same layer. The electron transport layer is disposed on a side of the anode layer away from the substrate, and the cathode layer is disposed on a side of the electron transport layer away from the substrate. The auxiliary electrode is disposed in an overlapping area and provided with a groove. An opening of the groove is toward the cathode layer, and the auxiliary electrode extends through the electron transport layer and is electrically connected with the cathode layer. By providing a groove on the side of the auxiliary electrode close to the cathode layer, the edge around the groove is formed with a scratching chamfer which facilitates the auxiliary electrode to extend through the electron transport layer and to contact with the cathode layer, thereby improving the conduction between the cathode layer and the auxiliary electrode. The technical problem that the conventional OLED display panel has a low yield when the electron transport layer covers the auxiliary electrode is alleviated. The mass production of the vapor deposition technology called one mask for Cathode/ET in the OLED display panel is feasible.
In the above-mentioned embodiments, the description of each embodiment has its own emphasis, and parts not described in detail in a certain embodiment may be referred to the related description of other embodiments.
The preparation method for OLED display panel and the OLED display panel provided in the embodiments of the present disclosure are described in detail, and the principles and embodiments of the present disclosure are described herein with specific examples. The description of the above embodiments is merely provided to help understand the method and the core idea of the present disclosure. At the same time, variations will occur to those skilled in the art in both the detailed description and the scope of disclosure in accordance with the teachings of the present disclosure. In conclusion, the present description should not be construed as limiting the disclosure.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202211358665.0 | Nov 2022 | CN | national |
