Built-in cathode ring structure, display device and display device manufacturing method

Abstract

The invention discloses a built-in cathode ring structure, a display device and a manufacturing method of the display device, and belongs to the technical field of display, the built-in cathode ring structure comprises a first conductive part and a second conductive part, the first conductive part is used for being arranged on one side, close to a chip, of an anode layer of a sub-pixel, and the first conductive part is used for being connected to a cathode ring; the pixel extension layer extends to the vicinity of the pixel definition layer; the second conductive part is arranged in the pixel definition layer, one end of the second conductive part is connected to the cathode layer of the sub-pixel, and the other end of the second conductive part is connected to the first conductive part. The pixel definition layer is provided with the second conductive part communicating the cathode layer and the first conductive part, the first conductive part is connected with the cathode ring, the first conductive part and the second conductive part are used for bearing the task of voltage distribution, the thickness of the cathode layer can be made to be thin so as to improve the transmittance, and therefore the relation between the transmittance and the conductivity of the cathode layer is taken into consideration; the double targets of high transmittance and high conductivity are achieved, and high-quality display is achieved.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a built-in cathode ring structure, a display device and a method for manufacturing the display device. Background Art

[0002] In the field of display technology, silicon-based OLED (organic light-emitting diode) products have become an important part of modern display technology due to their significant advantages such as high brightness, high contrast, fast response and low power consumption. Especially in high-end display devices, the application of silicon-based OLED is becoming more and more extensive, and the requirements for display effects are also increasing. However, in the design and manufacturing process of silicon-based OLED products, a key technical difficulty is how to optimize the cathode structure between each sub-pixel to meet specific performance requirements.

[0003] In silicon-based OLED products, in order to achieve efficient light emission and effective light extraction, the cathodes between each sub-pixel are designed to be interconnected. This design not only requires the cathode material to have good conductivity to ensure uniform distribution and efficient transmission of current, but also requires the cathode material to have sufficient transparency to achieve the top emission mode, so that light can pass through the device smoothly and achieve the expected display effect. Therefore, the selection of cathode materials has become a crucial link.

[0004] At present, commonly used cathode materials such as ITO (indium tin oxide) and IZO (indium zinc oxide) meet the requirements of transparency and conductivity to a certain extent, but there is an inherent trade-off between the two in terms of performance. Specifically, high transmittance is often accompanied by low conductivity, while high conductivity is often accompanied by low transmittance. This trade-off relationship limits the further improvement of silicon-based OLED products in performance, especially in relatively large-sized products, such as products of 1 inch and above, where the problem is particularly prominent.

[0005] In large-size silicon-based OLED products, low conductivity can lead to cathode voltage drop, which means that when current passes through the cathode, voltage loss will occur, which will affect the product's image quality. This image quality problem may manifest as mura (i.e. uneven screen brightness or color) or other forms of uneven images, which seriously affects the user's visual experience.

[0006] Therefore, how to ensure the transparency of the cathode material while improving its conductivity, so as to achieve the dual goals of high transmittance and high conductivity in large-size silicon-based OLED products, has become a technical problem that needs to be solved urgently. Summary of the invention

[0007] The purpose of the present invention is to provide a built-in cathode ring structure, a display device and a method for manufacturing a display device to solve the problems existing in the above-mentioned prior art. By utilizing the first conductive member and the second conductive member to undertake the task of voltage distribution, the cathode layer can be made thinner to improve the transmittance, thereby taking into account the relationship between the transmittance and conductivity of the cathode layer, achieving the dual goals of high transmittance and high conductivity, and realizing high-quality display.

[0008] To achieve the above object, the present invention provides the following solutions:

[0009] The present invention provides a built-in cathode ring structure, comprising a first conductive member and a second conductive member, wherein the first conductive member is used to be arranged on a side of an anode layer of a sub-pixel close to a chip, the first conductive member is used to be connected to the cathode ring, and extends to the vicinity of a pixel definition layer; the second conductive member is arranged in the pixel definition layer, one end of the second conductive member is connected to the cathode layer of the sub-pixel, and the other end of the second conductive member is connected to the first conductive member.

[0010] In one embodiment, the first conductive member is a metal sheet, and the metal sheet is used to be laid flat on the inner side of the cathode ring.

[0011] In one embodiment, the longitudinal cross-section of the second conductive member is a T-shaped structure, the outer side of the horizontal arm of the T-shaped structure is connected to the cathode layer, and the bottom end of the vertical arm of the T-shaped structure is connected to the first conductive member.

[0012] In one embodiment, the first conductive member is made of a single metal or a stacked metal or alloy selected from Cu, Al, Mo, and W.

[0013] In one embodiment, the second conductive member is made of a single metal or a stacked metal or an alloy selected from Cu, Al, Mo, and W.

[0014] The present invention provides a display device, including a cathode ring and a built-in cathode ring structure as described above, wherein sub-pixels and a pixel definition layer are arranged on the inner side of the cathode ring, the pixel definition layer is located around the sub-pixel, and the surface and bottom of the sub-pixel are respectively provided with a cathode layer and an anode layer, the anode layer is connected to a chip, and the cathode layer is connected to the cathode ring; the first conductive member is connected to the cathode ring, one end of the second conductive member is connected to the cathode layer, and the other end of the second conductive member is connected to the first conductive member.

[0015] In one embodiment, the pixel definition layer includes a first non-conductive layer and a second non-conductive layer, the first non-conductive layer and the second non-conductive layer are respectively located on the upper and lower sides of the second conductive member, and the second conductive member penetrates the second non-conductive layer and is connected to the first conductive member.

[0016] In one embodiment, the first non-conductive layer is made of a single material or a stacked layer of SiO, SiN, and SiON.

[0017] In one embodiment, the second non-conductive layer is made of a single material or a stacked layer of SiO, SiN, and SiON.

[0018] The present invention provides a method for manufacturing a display device, comprising the following steps:

[0019] S1, forming a film on the incoming material on which the first conductive member and the anode layer have been set to form a second non-conductive layer;

[0020] S2, etching a through space in the second non-conductive layer for the second conductive member to connect to the first conductive member;

[0021] S3, forming a film on the second non-conductive layer to form a second conductive member;

[0022] S4, forming a film on the second conductive member to form a first non-conductive layer;

[0023] S5, etching the first non-conductive layer and the second conductive member to form sub-pixels and a pixel definition layer;

[0024] S6, evaporating OLED devices on the sub-pixels and the pixel definition layer;

[0025] S7, forming a film on the surface of the OLED device to form a cathode layer.

[0026] Compared with the prior art, the present invention has achieved the following technical effects:

[0027] In the present invention, a second conductive member connecting the cathode layer and the first conductive member is provided in the pixel definition layer, and the first conductive member is connected to the cathode ring. The first conductive member and the second conductive member are used to perform the task of voltage distribution, so that the cathode layer can be made thinner to improve the transmittance, thereby taking into account the relationship between the transmittance and conductivity of the cathode layer, achieving the dual goals of high transmittance and high conductivity, and realizing high-quality display. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0029] Figure 1 It is a schematic diagram of the cross-sectional structure of a display device in an embodiment of the present invention;

[0030] Figure 2 The process steps of the method for manufacturing a display device in an embodiment of the present invention;

[0031] Among them, 1. first conductive element; 2. second conductive element; 3. sub-pixel; 4. pixel definition layer; 41. first non-conductive layer; 42. second non-conductive layer; 5. cathode layer; 6. anode layer; 7. chip; 8. cathode ring. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] The purpose of the present invention is to provide a built-in cathode ring structure, a display device and a method for manufacturing a display device to solve the problems existing in the prior art. By utilizing the first conductive member and the second conductive member to undertake the task of voltage distribution, the cathode layer can be made thinner to improve the transmittance, thereby taking into account the relationship between the transmittance and conductivity of the cathode layer, achieving the dual goals of high transmittance and high conductivity, and realizing high-quality display.

[0034] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0035] The solution for lighting up the OLED display terminal is to apply a certain voltage to the anode (Anode) and cathode (Cathode) of the OLED. The picture is displayed through the chip (CMOS) under the anode, controlling the anodes of different areas to apply different voltages at different times, and the cathodes of all sub-pixels to continuously apply a constant voltage through the cathode ring (Cathode-ring), thereby achieving different pictures. Because the display device has a certain area, that is, it will produce surface resistance, when the current passes through the cathode, it will produce a voltage drop, resulting in the voltage applied to the OLED in different areas not being equal to the designed voltage, so the picture is distorted, and the larger the area of ​​the display device, the more serious the distortion. The cathode itself has a light-transmitting requirement. While reducing the surface resistance (need to increase the cathode thickness), it is bound to lead to a decrease in light transmittance.

[0036] The above and below mentioned in the present invention are based on Figure 1 In the orientation shown, the surface mentioned refers to Figure 1 The top is shown, the bottom refers to Figure 1 shown below.

[0037] like Figure 1 and Figure 2 As shown, the present invention provides a built-in cathode ring structure, including a first conductive member 1 and a second conductive member 2. The first conductive member 1 and the second conductive member 2 have higher conductivity than the cathode layer 5. Through the conductive mode of the first conductive member 1 and the second conductive member 2, the voltage applied to the cathode layer 5 of the sub-pixel 3 hardly has a significant voltage drop as the OLED display area increases. The first conductive member 1 is used to be arranged below the anode layer 6 of the sub-pixel 3, that is, located on the side of the anode layer 6 close to the chip 7. The first conductive member 1 is insulated from the anode layer 6. The first conductive member 1 and the anode layer 6 can be prepared when or after the chip 7 is prepared (before the built-in cathode ring structure is prepared). The first conductive member 1 is used to connect to the cathode ring 8 and extend to the vicinity of the pixel definition layer 4, so that the voltage of the cathode ring 8 can be distributed to the second conductive member 2 of each pixel definition layer 4 by using the first conductive member 1. The second conductive member 2 is disposed in the pixel definition layer 4, and the pixel definition layer 4 can be used to achieve insulation between the second conductive member 2 and the surroundings, and allow the second conductive member 2 to penetrate the pixel definition layer 4. On the one hand, it can be upward so that one end of the second conductive member 2 is connected to the cathode layer 5 of the sub-pixel 3, and on the other hand, it can be downward so that the other end of the second conductive member 2 is connected to the first conductive member 1.

[0038] In the present invention, a second conductive member 2 connecting the cathode layer 5 and the first conductive member 1 is provided on the pixel definition layer 4, and the first conductive member 1 is connected to the cathode ring 8. The first conductive member 1 and the second conductive member 2 are used to perform the task of voltage distribution, so that the cathode layer 5 can be made thinner to improve the transmittance, thereby taking into account the relationship between the transmittance and conductivity of the cathode layer 5, achieving the dual goals of high transmittance and high conductivity, and realizing high-quality display.

[0039] In one embodiment, the first conductive member 1 is a metal sheet, which is laid flat on the inner side of the cathode ring 8 to connect the second conductive member 2 and the cathode layer 5 from the display area to the outer cathode ring 8. The metal sheet has good electrical conductivity, and the voltage at any point on its surface will not drop significantly as the distance from the cathode ring 8 increases.

[0040] In one embodiment, the longitudinal cross-section of the second conductive member 2 is a T-shaped structure, the outer side of the horizontal arm of the T-shaped structure is connected to the cathode layer 5, and the bottom end of the vertical arm of the T-shaped structure is connected to the first conductive member 1, thereby achieving electrical conduction between the first conductive member 1 and the cathode layer 5. The T-shaped structure itself has good electrical conductivity, and distributes the voltage of the first conductive member 1 to the cathode layer 5 of the sub-pixel 3 corresponding to the pixel definition layer 4.

[0041] In one embodiment, the first conductive member 1 is made of any metal such as copper (Cu), aluminum (Al), molybdenum (Mo), tungsten (W), etc., and may also be a laminated metal formed by two or more metals, or may also be an alloy.

[0042] In one embodiment, the second conductive member 2 is made of any metal such as copper (Cu), aluminum (Al), molybdenum (Mo), tungsten (W), etc., and may also be a laminated metal formed by two or more metals, or may also be an alloy.

[0043] like Figure 1 and Figure 2 As shown, the present invention provides a display device, including a cathode ring 8 and a built-in cathode ring structure as described above, wherein a sub-pixel 3 and a pixel definition layer 4 are arranged inside the cathode ring 8, the pixel definition layer 4 is located around the sub-pixel 3, and a cathode layer 5 and an anode layer 6 are arranged on the surface and bottom of the sub-pixel 3, respectively, the anode layer 6 is connected to the chip 7, and the cathode layer 5 is connected to the cathode ring 8. The anode layers 6 in different areas are controlled by the chip 7 to apply different voltages at different times, and the cathode layers 5 of all sub-pixels 3 are continuously applied with a constant voltage through the cathode ring 8, so as to realize different pictures. The first conductive member 1 is connected to the cathode ring 8, one end of the second conductive member 2 is connected to the cathode layer 5, and the other end of the second conductive member 2 is connected to the first conductive member 1. The voltage of the cathode ring 8 is distributed to the cathode layers 5 of different sub-pixels 3 through the first conductive member 1 and the second conductive member 2, so that the cathode layer 5 itself no longer bears the task of distributing the voltage, and it can be made thinner to improve the transmittance, and finally realize that the cathode layer 5 has high transmittance and high conductivity (lower voltage drop).

[0044] In one embodiment, the pixel definition layer 4 is used for pixel definition, and includes a first non-conductive layer 41 and a second non-conductive layer 42. The first non-conductive layer 41 and the second non-conductive layer 42 are respectively located at the upper and lower sides of the second conductive member 2. The second conductive member 2 penetrates the second non-conductive layer 42 and is connected to the first conductive member 1. The first non-conductive layer 41 is used to cut off the OLED organic material during the evaporation process so that the organic materials between the sub-pixels 3 are not connected. The second non-conductive layer 42 is used to prevent the second conductive member 2 from being short-circuited with the anode layer 6.

[0045] In one embodiment, the first non-conductive layer 41 is made of any one of silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), etc., or a stacked layer formed by two or more materials.

[0046] In one embodiment, the second non-conductive layer 42 is made of any one of silicon oxide (SiO), silicon nitride (SiN), silicon oxynitride (SiON), etc., or is a stacked layer formed by two or more materials.

[0047] like Figure 1 and Figure 2 As shown, the present invention provides a method for manufacturing a display device, comprising the following steps:

[0048] S1, forming a film on the incoming material on which the first conductive member 1 and the anode layer 6 have been set, to form a second non-conductive layer 42. At this time, the second non-conductive layer 42 is formed as a whole layer, and subsequent steps are required to obtain the final size;

[0049] S2, etching the second non-conductive layer 42 of step S1 to form the final size of the second non-conductive layer 42, and etching a through space in the second non-conductive layer 42 for the second conductive member 2 to connect to the first conductive member 1;

[0050] S3, forming a film on the second non-conductive layer 42 to form a second conductive member 2. At this time, the second conductive member 2 is formed as a whole layer, and subsequent steps are required to obtain a final size;

[0051] S4, the second conductive member 2 in step S3 continues to form a film to form a first non-conductive layer 41. At this time, the first non-conductive layer 41 is formed as a whole layer, and subsequent steps are required to obtain a final size;

[0052] S5, etching the first non-conductive layer 41 and the second conductive member 2 in step S4 to form sub-pixels 3 and a pixel definition layer 4;

[0053] S6, evaporating OLED devices on the sub-pixel 3 and the pixel definition layer 4;

[0054] S7, forming a film on the surface of the OLED device to form a cathode layer 5.

[0055] like Figure 2 As shown, the process steps of the embodiment provided by the present invention are as follows:

[0056] Step 0: Incoming materials, Anode (anode layer 6) completed.

[0057] Step 1: PDL-inorganic (second non-conductive layer 42) film formation (CVD process).

[0058] Step 2: PDL-inorganic (second non-conductive layer 42) yellow light process.

[0059] Step 3: PDL-inorganic (second non-conductive layer 42) etching process + stripper (stripping).

[0060] Step 4: PDL-Metal (second conductive element 2) + Inorganic (first non-conductive layer 41) film formation, using PVD and CVD processes respectively.

[0061] Step 5: PDL-Metal (second conductive element 2) + Inorganic (first non-conductive layer 41) yellow light process.

[0062] Step 6: PDL-Metal (second conductive part 2) + Inorganic (first non-conductive layer 41) etching + stripper (stripping) process. Etching can be divided into multiple steps. It should be pointed out that: a structure in which the top layer of inorganic (first non-conductive layer 41) exceeds the metal (second conductive part 2) by a certain length in the horizontal direction must be formed here. Specifically, the first step is to etch the top layer of inorganic (first non-conductive layer 41) and metal (second conductive part 2) at one time to form a continuous side edge; the second step is to etch a part of the metal (second conductive part 2) inward in the horizontal direction.

[0063] Step 7: Evaporation process of OLED device (excluding cathode layer 5).

[0064] Step 8: cathode (cathode layer 5) film forming process.

[0065] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A built-in cathode ring structure, characterized in that: include: A first conductive member, the first conductive member is used to be arranged on a side of the anode layer of the sub-pixel close to the chip, the first conductive member is used to be connected to the cathode ring, and extends to the vicinity of the pixel definition layer; and a second conductive member, wherein the second conductive member is disposed in the pixel definition layer, one end of the second conductive member is connected to the cathode layer of the sub-pixel, and the other end of the second conductive member is connected to the first conductive member.

2. The built-in cathode ring structure according to claim 1, characterized in that: The first conductive member is a metal sheet, and the metal sheet is used to be laid flat on the inner side of the cathode ring.

3. The built-in cathode ring structure according to claim 1, characterized in that: The longitudinal cross section of the second conductive member is a T-shaped structure, the outer side of the horizontal arm of the T-shaped structure is connected to the cathode layer, and the bottom end of the vertical arm of the T-shaped structure is connected to the first conductive member.

4. The built-in cathode ring structure according to claim 1, characterized in that: The first conductive member is made of a single metal or a laminated metal or alloy selected from Cu, Al, Mo, and W.

5. The built-in cathode ring structure according to claim 1, characterized in that: The second conductive member is made of a single metal or a laminated metal or an alloy selected from Cu, Al, Mo, and W.

6. A display device, characterized in that: include: A cathode ring, wherein a sub-pixel and a pixel definition layer are disposed on the inner side of the cathode ring, wherein the pixel definition layer is located around the sub-pixel, and a cathode layer and an anode layer are disposed on the surface and bottom surface of the sub-pixel, respectively, wherein the anode layer is connected to the chip, and the cathode layer is connected to the cathode ring; And the built-in cathode ring structure according to any one of claims 1 to 5, wherein the first conductive member is connected to the cathode ring, one end of the second conductive member is connected to the cathode layer, and the other end of the second conductive member is connected to the first conductive member.

7. The display device according to claim 6, characterized in that: The pixel definition layer includes a first non-conductive layer and a second non-conductive layer, wherein the first non-conductive layer and the second non-conductive layer are respectively located on the upper and lower sides of the second conductive member, and the second conductive member penetrates the second non-conductive layer and is connected to the first conductive member.

8. The display device according to claim 7, characterized in that: The first non-conductive layer is made of a single material or a stacked layer of SiO, SiN, and SiON.

9. The display device according to claim 7, characterized in that: The second non-conductive layer is made of a single material or a stacked layer of SiO, SiN, and SiON.

10. A method for manufacturing a display device, characterized in that: The following steps are involved: S1, forming a film on the incoming material on which the first conductive member and the anode layer have been set to form a second non-conductive layer; S2, etching a through space in the second non-conductive layer for the second conductive member to connect to the first conductive member; S3, forming a film on the second non-conductive layer to form a second conductive member; S4, forming a film on the second conductive member to form a first non-conductive layer; S5, etching the first non-conductive layer and the second conductive member to form sub-pixels and a pixel definition layer; S6, evaporating OLED devices on the sub-pixels and the pixel definition layer; S7, forming a film on the surface of the OLED device to form a cathode layer.

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