Manufacturing method of pixel unit, pixel unit and display panel
By using a pixel definition structure and removing the sacrificial layer during the pixel unit manufacturing process, and directly connecting it to the common cathode layer or encapsulation layer, the problem of poor stripping of OLED organic materials during photolithography and etching is solved, improving connection reliability and yield.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- ANHUI SEMICON INTEGRATED DISPLAY TECH CO LTD
- Filing Date
- 2026-03-30
- Publication Date
- 2026-06-30
AI Technical Summary
In the manufacturing of pixel units, existing technologies for OLED organic materials are prone to poor peeling during photolithography and etching processes, leading to connection failure and affecting yield.
By fabricating pixel definition structures on the substrate and stripping the sacrificial layer to remove the organic light-emitting layer, the connection is enhanced and poor stripping is avoided by directly connecting it to the common cathode layer or encapsulation layer.
This improves the connection effect of pixel units, avoids poor peeling, and enhances the reliability of the manufacturing process.
Smart Images
Figure CN122318698A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of organic light-emitting diode microdisplay technology, and more specifically, to a method for manufacturing a pixel unit, the pixel unit, and a display panel. Background Technology
[0002] When manufacturing pixel units using photolithography, a mask is typically needed in the target pixel area to remove the OLED structure from the remaining pixel areas.
[0003] In this approach, OLED organic material is located above the pixel definition area. Therefore, the pixel definition area needs to be connected to the cathode layer and the thin-film encapsulation (TFE) layer above it via the OLED organic material. Since OLED organic material itself is usually quite fragile, it is prone to poor peeling during subsequent photolithography and etching processes, which can lead to failure of protection for the OLED device and affect yield. Summary of the Invention
[0004] The purpose of this invention is to provide a method for manufacturing a pixel unit, a pixel unit, and a display panel. Using this method, the pixel definition structure can be directly connected to the upper common cathode layer or encapsulation layer, increasing the connection force and improving the connection effect.
[0005] To achieve the above objectives, the present invention provides a method for manufacturing a pixel unit, comprising the following steps: S1: An anode layer is fabricated on one side of the substrate, such that the anode layer includes a first anode structure located in a first pixel region, a second anode structure located in a second pixel region, and a third anode structure located in a third pixel region; S2. On the substrate obtained in S1, a pixel definition layer and a first stripping sacrificial layer are sequentially fabricated. The pixel definition layer and the first stripping sacrificial layer on the anode layer are removed to obtain a pixel definition structure and a first stripping sacrificial structure covering the pixel definition structure. S3. On the substrate obtained in S2, an initial first organic light-emitting layer is fabricated, and the first stripping sacrificial structure is peeled off to obtain an intermediate first organic light-emitting layer located on the first anode structure, the second anode structure and the third anode structure. S4. On the substrate obtained in S3, a first cathode layer and a first protective layer are sequentially fabricated. The first protective layer, the first cathode layer and the intermediate first organic light-emitting layer located in the second pixel region and the third pixel region are removed to obtain a first organic light-emitting structure, a first cathode structure and a first protective structure located in the first pixel region.
[0006] Preferably, it further includes: S5. Fabricate a second stripping sacrificial layer on the substrate obtained in S4, remove the second stripping sacrificial layer on the anode layer, and obtain a second stripping sacrificial structure located on the pixel definition structure. S6. Fabricate an initial second organic light-emitting layer on the substrate, peel off the second peeling sacrificial structure, and obtain an intermediate second organic light-emitting layer located on the anode layer; S7. Sequentially fabricate a second cathode layer and a second protective layer on the substrate, remove the second protective layer, the second cathode layer and the intermediate second organic light-emitting layer located in the first pixel area and the third pixel area, and obtain the second organic light-emitting structure, the second cathode structure and the second protective structure located in the second pixel area.
[0007] Preferably, it further includes: S8. Fabricate a third stripping sacrificial layer on the substrate obtained in S7, remove the third stripping sacrificial layer on the anode layer, and obtain a third stripping sacrificial structure located on the pixel definition structure. S9. Fabricate an initial third organic light-emitting layer on the substrate obtained in S8, and peel off the third peeling sacrificial structure to obtain an intermediate third organic light-emitting layer located on the anode layer. S10. On the substrate obtained in S9, a third cathode layer and a third protective layer are sequentially fabricated. The third protective layer, the third cathode layer and the intermediate third organic light-emitting layer located in the first pixel region and the second pixel region are removed to obtain a third organic light-emitting structure, a third cathode structure and a third protective structure located in the third pixel region.
[0008] Preferably, step S2 includes: The pixel definition layer and the first stripping sacrificial layer are patterned to obtain pixel openings corresponding to the first anode structure, the second anode structure, and the third anode structure.
[0009] Preferably, after step S10, the method further includes: S11: Under the mask of the mask, remove part of the first protective structure, part of the second protective structure and part of the third protective structure to expose part of the first cathode structure, part of the second cathode structure and part of the third cathode structure located above the pixel definition structure.
[0010] Preferably, after step S10, the method further includes: S11: Under the mask of the photomask, remove part of the first protective structure, part of the second protective structure and part of the third protective structure to expose part of the first cathode structure, part of the second cathode structure and part of the third cathode structure located above the first anode structure, the second anode structure and the third anode structure.
[0011] Preferably, after step S11, the method further includes: S12: Create a common cathode layer such that it covers the exposed portions of the first cathode structure, the second cathode structure, and the third cathode structure.
[0012] Preferably, step S2 includes: The pixel definition layer and the first stripping sacrificial layer are patterned to obtain a plurality of strip-shaped pixel definition structures spaced apart along the first direction, so that an exposed channel without a pixel definition layer is formed between adjacent anode structures in the second direction. The first direction and the second direction are both parallel to the substrate and perpendicular to each other.
[0013] Preferably, the first cathode structure, the second cathode structure, and the third cathode structure all cover the anode structure and the exposed channel, and are electrically connected to the outer cathode ring through the exposed channel.
[0014] The present invention also provides a pixel unit, which is manufactured by a pixel unit manufacturing method, comprising: A substrate, on which an anode layer and a pixel definition structure are disposed, the anode layer including a first anode structure, a second anode structure and a third anode structure; The first organic light-emitting structure, the first cathode structure, and the first protective structure are located on the first anode structure.
[0015] Preferably, it further includes: The second organic light-emitting structure, the second cathode structure, and the second protective structure are located on the second anode structure; The third organic light-emitting structure, the third cathode structure, and the third protective structure are located on the third anode structure.
[0016] Preferably, the pixel definition structure is provided with pixel openings, which correspond to the first anode structure, the second anode structure and the third anode structure respectively; Conductive channels are provided on the surfaces of the first protective structure, the second protective structure, and the third protective structure. The first cathode structure, the second cathode structure, and the third cathode structure expose cathode connection areas through the conductive channels. The common cathode layer is electrically connected to the first cathode structure, the second cathode structure, and the third cathode structure through the cathode connection areas.
[0017] Preferably, the conductive channel is located above the pixel definition structure.
[0018] Preferably, the conductive channel is located above the anode layer.
[0019] Preferably, multiple pixel definition structures are provided, and the multiple pixel definition structures are arranged at intervals along the first direction, forming an exposure channel between adjacent anode structures in the second direction; The first, second, and third cathode structures all cover the anode structure and the exposed channel, and are electrically connected to the outer cathode ring through the exposed channel.
[0020] Both the first and second directions are parallel to the base and perpendicular to each other.
[0021] The present invention also provides a display panel comprising an array of pixel units.
[0022] According to the above technical solution, the present invention uses a pixel unit manufacturing method that, by utilizing a first peeling sacrificial structure located on the pixel definition structure, can effectively remove the organic light-emitting layer on the pixel definition structure. This allows the pixel definition structure to be directly connected to the upper common cathode layer or encapsulation layer, increasing the connection force, improving the connection effect, and avoiding poor peeling.
[0023] Other features and advantages of the present invention will be described in detail in the following detailed description section. Attached Figure Description
[0024] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used together with the following detailed description to explain the invention, but do not constitute a limitation thereof. In the drawings: Figure 1 This is a flowchart of a pixel unit manufacturing method provided in an embodiment of the present invention; Figure 2-23 This is a schematic diagram of the structure corresponding to each step in the manufacturing method of the pixel unit provided in the embodiment of the present invention.
[0025] Explanation of reference numerals in the attached figures 10 Substrate; 21 First Anode Structure; 22 Second Anode Structure; 23 Third Anode Structure; 11 Pixel Definition Layer; 1 Pixel Definition Structure; 611 First Release Sacrificial Layer; 61 First Release Sacrificial Structure; 311 First Organic Light Emitting Layer; 312 Intermediate First Organic Light Emitting Layer; 411 First Cathode Layer; 511 First Protective Layer; 31 First Organic Light Emitting Structure; 41 First Cathode Structure; 51 First Protective Structure; 62 Second Release Sacrificial Structure; 321 Initial Second Organic Light Emitting Layer; 322 Intermediate Second Organic Light Emitting Layer; 421 Second Cathode Layer; 521 Second Protective Layer; 32 Second Organic Light Emitting Structure; 42 Second Cathode Structure; 52 Second Protective Structure; 33 Third Organic Light Emitting Structure; 43 Third Cathode Structure; 53 Third Protective Structure; 12 Pixel Opening; 13 Exposed Channel; 7 Common Cathode Layer; 101 Cathode Ring; 71 Conductive Channel; 72 Cathode Connection Area; 9 Encapsulation Layer; 60 Photoresist; 61 Mask. Detailed Implementation
[0026] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.
[0027] In this invention, unless otherwise stated, directional terms included in the terminology represent only the orientation of the term in its normal use or as commonly understood by those skilled in the art, and should not be regarded as a limitation on the term.
[0028] Figure 1 This is a schematic flowchart of a pixel unit manufacturing method provided in an embodiment of the present invention. Figure 2-17 This is a structural diagram corresponding to each step in the manufacturing method of a pixel unit. The manufacturing method provided in this embodiment of the invention includes the following steps: S1: An anode layer is fabricated on one side of the substrate 10, such that the anode layer includes a first anode structure 21 located in a first pixel region, a second anode structure 22 located in a second pixel region, and a third anode structure 23 located in a third pixel region; Specifically, such as Figure 2 As shown, an anode structure is first fabricated on the substrate 10, with multiple anode structures spaced apart to form a first anode structure 21, a second anode structure 22, and a third anode structure 23. The anode material can be ITO, ITO / Ag / ITO, or other transparent conductive materials.
[0029] S2. A pixel definition layer 11 and a first stripping sacrificial layer 611 are sequentially fabricated on the substrate 10 obtained in S1. The pixel definition layer 11 and the first stripping sacrificial layer 611 on the anode layer are removed to obtain a pixel definition structure 1 and a first stripping sacrificial structure 61 covering the pixel definition structure 1. Specifically, such as Figure 3 As shown, a pixel definition layer (PDL) 11 and a first release sacrificial layer 611 are sequentially fabricated on a substrate 10 to obtain a PDL+sacrificial layer stacked structure. The pixel definition layer (PDL) 11 can be an organic insulating material, such as photosensitive polyimide, acrylic resin, epoxy resin, or an inorganic / organic composite material. The first release sacrificial layer 611 is a peelable material layer, which can be a soluble and peelable organic material, a thermally peelable material, or a multi-layer peelable structure, such as a double-layer structure of a bottom release layer + an upper protective layer, to meet the peelability and selectivity in the subsequent peeling process.
[0030] Photolithography is performed on the PDL+sacrificial layer stacked structure. Optionally, a patterned mask is formed on the surface of the substrate 10; then an etching process is performed on the exposed area to form a pixel opening 12 in the pixel region of the PDL+sacrificial layer stacked structure. The pixel opening 12 corresponds to the anode structure, that is, the anode structure is exposed at the position of the pixel opening 12, and a pixel definition structure 1 is formed around the pixel opening 12. The top of the pixel definition structure 1 is continuously covered by the first stripping sacrificial structure 61, see... Figure 4 .
[0031] The etching process can be dry etching, wet etching, or a combination of both. When the pixel definition layer 11 (PDL) and the first stripping sacrificial layer 611 have different materials or different etching rates, segmented etching or selective etching processes can be used to ensure that the opening morphology meets the requirements of subsequent evaporation and stripping of organic light-emitting materials (OLED).
[0032] When depositing the pixel definition layer (PDL) 11, the PDL 11 can be deposited as a single-layer or multi-layer structure. The deposition process can be physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), etc. Taking a two-layer structure as an example, when depositing the first PDL layer, easily etchable materials are generally selected, including but not limited to silicon nitride, silicon oxide, and silicon oxynitride. When depositing the second PDL layer, difficult-to-etch materials are generally selected, including but not limited to silicon oxide, aluminum oxide, and zirconium oxide. By using films with large differences in etching rates, the cross-sectional shape of the pixel definition structure 1 can be easily controlled, for example, the cross-section of the pixel definition structure 1 can be fabricated into a T-shaped structure. When the pixel definition layer 11 is a multi-layer structure, a multi-stage etching process is used to first etch the difficult-to-etch top layer, and then etch the easily etchable bottom layer, thereby etching a T-shaped pixel definition structure 1 that is wider at the top and narrower at the bottom. The undercut portion of the T-shaped pixel definition structure 1 can protect the OLED during subsequent organic material etching, preventing etching gases or chemicals from corroding the OLED device.
[0033] Even with a single-layer structure, the pixel definition layer 11 can still control the cross-sectional shape of the pixel definition structure 1. Optionally, the cross-section of the pixel definition structure 1 can be manufactured as a T-shaped structure. When selecting a single-layer pixel definition layer 11, a T-shaped structure that is wider at the top and narrower at the bottom can also be etched using a multi-stage etching process, first using physical etching and then using chemical etching.
[0034] The total thickness of pixel definition structure 1 is set to 30nm-500nm. This thickness is significantly higher than the sum of the heights of the anode structure and the organic light-emitting layer. In subsequent photolithography, etching, and cleaning processes, pixel definition structure 1, together with the cathode layer and the protective layer, reliably protects the sidewall structure of the organic light-emitting layer.
[0035] S3. An initial first organic light-emitting layer 311 is fabricated on the substrate 10 obtained in S2, and the first peeling sacrificial structure 61 is peeled off to obtain an intermediate first organic light-emitting layer 312 located on the first anode structure 21, the second anode structure 22 and the third anode structure 23. Specifically, such as Figure 5As shown, on the structure including the stripping sacrificial layer, optionally, the initial first organic light-emitting layer 311 is deposited integrally by a vapor deposition process, so that the initial first organic light-emitting layer 311 simultaneously covers the surface of the anode structure located in the pixel opening 12 region and the surface of the first stripping sacrificial structure 61 located on top of the pixel definition structure 1.
[0036] The first stripping sacrificial structure 61 is removed by a stripping process, thereby simultaneously removing the initial first organic light-emitting layer 311 located thereon. This results in the initial first organic light-emitting layer 311 deposited on top of the pixel definition structure 1 being stripped away, leaving only the initial first organic light-emitting layer 311 located on top of the anode structure, thus obtaining the intermediate first organic light-emitting layer 312. (See...) Figure 6 .
[0037] The stripping process can employ solvent stripping, thermal stripping, or a combination of both; during the stripping process, the first organic light-emitting structure 31 within the pixel opening 12 remains intact. Therefore, this method enables the reliable removal of the organic light-emitting material from the surface of the pixel structure 1 while protecting the first organic light-emitting structure 31 located above the anode structure, thus avoiding damage to the organic light-emitting material from the etching process.
[0038] S4. On the substrate 10 obtained in S3, a first cathode layer 411 and a first protective layer 511 are sequentially fabricated. The first protective layer 511, the first cathode layer 411 and the intermediate first organic light-emitting layer 312 located in the second pixel area and the third pixel area are removed to obtain a first organic light-emitting structure 31, a first cathode structure 41 and a first protective structure 51 located in the first pixel area.
[0039] Specifically, such as Figure 7 As shown, after removing the initial first organic light-emitting layer 311 at the top of the pixel definition structure 1, a first cathode layer 411 and a first protective layer 511 are sequentially fabricated on the substrate 10 to perform preliminary encapsulation and protection on the intermediate first organic light-emitting layer 312 above the anode structure.
[0040] Cathode layers are deposited using processes such as physical vapor deposition (PVD), chemical vapor deposition (CVD), or atomic layer deposition (ALD). Transparent cathode materials include, but are not limited to, indium zinc oxide (IZO), indium tin oxide (ITO), and indium gallium zinc oxide (IGZO). These cathode layers exhibit strong etching resistance and act as etch barrier layers, protecting underlying organic materials from etching damage. Protective layers can also be deposited using processes such as physical vapor deposition (PVD), chemical vapor deposition (CVD), or atomic layer deposition (ALD). Materials can include silicon oxide, silicon nitride, silicon oxynitride, aluminum oxide, titanium oxide, etc., and single-layer or multi-layer structures can be selected.
[0041] like Figure 8As shown, a photomask is used to transfer the designed pixel pattern to the photoresist layer and form the first photomask in the first pixel area.
[0042] In one embodiment, the first pixel region corresponds to the opaque area of the photomask, while the remaining areas are transparent. Under the action of this photomask, the photoresist 60 above the first pixel region is retained, while the photoresist in the remaining areas is dissolved, resulting in... Figure 9 The substrate shown.
[0043] Then, using the protective effect of photoresist 60, the intermediate first organic light-emitting layer 312, first cathode layer 411, and first protective layer 511 outside the first pixel area are etched to remove the OLED light-emitting structure in the non-target area, resulting in the first organic light-emitting structure 31, first cathode structure 41, and first protective structure 51 located above the first pixel area, as shown below. Figure 10 As shown.
[0044] When the first photomask is used to etch the first organic light-emitting layer 312, the first cathode layer 411 and the first protective layer 511 between the second pixel area and the third pixel area, the first organic light-emitting structure 31 located above the first anode structure 21 will be protected by the first cathode layer 411, the first protective layer 511 and the photoresist 60 located thereon, and the sidewall of the first organic light-emitting structure 31 will be protected by the pixel definition structure 1 adjacent to it.
[0045] After etching, plasma ashing can be performed, followed by NMP stripping of the photoresist 60 and drying; or a dry cleaning process can be used to directly remove the photoresist 60 residue after etching.
[0046] Therefore, using this pixel unit manufacturing method, the organic light-emitting layer on the pixel definition structure 1 is removed using the first peeling sacrificial structure 61. The pixel definition structure 1 can be directly connected to the upper common cathode layer 7 or encapsulation layer 9, increasing the connection force, improving the connection effect, and avoiding the occurrence of poor peeling.
[0047] Optionally, in this embodiment, it further includes: S5. A second stripping sacrificial layer is fabricated on the substrate 10 obtained in S4. The second stripping sacrificial layer on the anode layer is removed to obtain the second stripping sacrificial structure 62 located on the pixel definition structure 1. Specifically, such as Figure 11 As shown, a second release sacrificial layer is fabricated on the substrate 10, and the second release sacrificial layer on the anode layer is removed by a patterning method to obtain the second release sacrificial structure 62 located on the pixel definition structure 1.
[0048] S6. An initial second organic light-emitting layer 321 is fabricated on the substrate 10, and the second stripping sacrificial structure 62 is peeled off to obtain an intermediate second organic light-emitting layer 322 located on the anode layer. Specifically, such as Figure 12 As shown, an initial second organic light-emitting layer 321 is fabricated on the substrate 10. The second lift-off sacrificial structure 62 is removed using a lift-off process, and the initial second organic light-emitting layer 321 located thereon is also removed. This results in the initial second organic light-emitting layer 321 deposited on top of the pixel definition layer 11 being peeled off, leaving only the initial second organic light-emitting layer 321 located on the anode structure, thus obtaining an intermediate second organic light-emitting layer 322 located on the anode layer. Figure 13 .
[0049] S7. A second cathode layer 421 and a second protective layer 521 are sequentially fabricated on the substrate 10. The second protective layer 521, the second cathode layer 421 and the intermediate second organic light-emitting layer 322 located in the first pixel area and the third pixel area are removed to obtain the second organic light-emitting structure 32, the second cathode structure 42 and the second protective structure 52 located in the second pixel area.
[0050] Specifically, such as Figure 14 As shown, a second cathode layer 421 and a second protective layer 521 are sequentially fabricated on the substrate 10 to protect the intermediate second organic light-emitting layer 322 located in the second pixel area during subsequent etching.
[0051] The designed pixel pattern is transferred to the photoresist layer using a photomask, and photoresist 60 is formed in the second pixel area. (See...) Figure 15 .
[0052] like Figure 16 The second organic light-emitting layer 322, the second cathode layer 421 and the first protective layer 511 outside the second pixel area are etched using the protective effect of the photoresist 60 to remove the OLED light-emitting structure in the non-target area, thereby obtaining the second organic light-emitting structure 32, the second cathode structure 42 and the second protective structure 52 located above the second pixel area.
[0053] Optionally, in this embodiment, it further includes: S8. A third stripping sacrificial layer is fabricated on the substrate 10 obtained in S7. The third stripping sacrificial layer on the anode layer is removed to obtain the third stripping sacrificial structure located on the pixel definition structure 1. S9. On the substrate 10 obtained in S8, an initial third organic light-emitting layer is fabricated, and the third stripping sacrificial structure is stripped to obtain an intermediate third organic light-emitting layer located on the anode layer. S10. On the substrate 10 obtained in S9, a third cathode layer and a third protective layer are sequentially fabricated. The third protective layer, the third cathode layer and the intermediate third organic light-emitting layer located in the first pixel area and the second pixel area are removed to obtain the third organic light-emitting structure 33, the third cathode structure 43 and the third protective structure 53 located in the third pixel area.
[0054] Using the same method, the third organic light-emitting structure 33, the third cathode structure 43, and the third protective structure 53 can be obtained in the third pixel region, see [link to documentation]. Figure 17 .
[0055] Optionally, in this embodiment, step S2 includes: The pixel definition layer 11 and the first stripping sacrificial layer 611 are patterned to obtain pixel openings 12 corresponding to the first anode structure 21, the second anode structure 22 and the third anode structure 23.
[0056] Specifically, such as Figure 3 As shown, a pixel definition layer 11 and a first stripping sacrificial layer 611 are sequentially fabricated on the substrate 10 to obtain a stacked structure of PDL+sacrificial layer.
[0057] Optionally, in this embodiment, after step S10, the method further includes: S11: Under the mask of the mask plate 61, remove part of the first protective structure 51, part of the second protective structure 52 and part of the third protective structure 53 to expose part of the first cathode structure 41, part of the second cathode structure 42 and part of the third cathode structure 43 located above the pixel definition structure 1.
[0058] Specifically, such as Figure 19 As shown, after removing portions of the first protective structure 51, the second protective structure 52, and the third protective structure 53, a conductive channel 71 is formed above the cathode layer. This conductive channel 71 exposes portions of the first cathode structure 41, the second cathode structure 42, and the third cathode structure 43 located above the pixel definition structure 1. Then, by covering the common cathode layer 7, the common cathode layer 7 is electrically connected to the exposed portions of each cathode layer through the conductive channel 71. This achieves the purpose of electrically connecting the common cathode layer 7 to the cathode layer above each anode structure. Figure 20 .
[0059] In one embodiment, a coating exposure and development process is used to form conductive channels 71 on the pixels. These channels connect the cathode layer of each pixel to a common cathode layer 7, enabling cathode power supply.
[0060] The conductive channel 71 is etched and the resist is removed using dry or wet etching, or a combination of dry and wet etching is used to etch through the protective structure and stop at the cathode structure, so that the cathode structure is exposed through the conductive channel 71.
[0061] The common cathode layer 7 is deposited using processes such as physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or evaporation. The cathode materials used include, but are not limited to, indium zinc oxide (IZO), indium tin oxide (ITO), indium gallium zinc oxide (IGZO), and Mg / Ag. During the deposition of the common cathode layer 7, cathode material is deposited into and fills the conductive channels 71. In this way, the common cathode connects the cathode structure of each pixel to the common cathode layer 7, enabling cathode power supply.
[0062] When a positive voltage is applied to the bottom anode layer, electrons are injected from the common cathode layer 7, and holes are injected from the anode, recombine to emit light in the light-emitting layer. The common cathode layer 7 provides a unified source of electron injection and a current return path for all pixels. Therefore, independent control of each pixel is achieved through this combination of a bottom-separated anode and a top-shared cathode.
[0063] In one embodiment, a layer of photoresist 60 is first coated on the substrate 10. A photomask is then used to transfer the designed pixel pattern to the photoresist 60 layer, forming a photomask 61 above the anode structure. Specifically, the area above the anode structure corresponds to the opaque region of the photomask, while the remaining areas are transparent. Under the action of this photomask, the photoresist 60 above the anode structure is retained to form the photomask 61, while the photoresist 60 in the remaining areas is dissolved. Subsequently, the protective layer outside the anode structure is etched using the protective effect of the photomask 61, exposing a ring of cathode layers outside the anode structure.
[0064] Preferably, the positions between two adjacent pixel areas can also correspond to the opaque areas of the photomask, so that the photomask 61 also includes the connection positions between two adjacent pixel areas, see Figure 18 The mask 61 includes the connection position between two adjacent pixel areas, so that when the protective layer is etched, the gap position between two adjacent pixel areas can be protected by the photoresist 60, avoiding the impact of etching on the organic light-emitting layer, and playing the role of protecting the organic light-emitting layer.
[0065] Under the action of this photomask, the photoresist 60 above the anode structure and the photoresist 60 at the connection positions between two adjacent pixel areas are both preserved, forming a photomask 61. Utilizing the protective effect of the photomask 61, the protective layer is etched, removing a ring of protective layer around the anode structure to form a ring of channels surrounding the anode structure, exposing a ring of cathode connection regions 72 surrounding the anode structure. Figure 19 .
[0066] Optionally, in this embodiment, after step S10, the method further includes: S11: Under the mask of the mask plate 61, a portion of the first protective structure 51, a portion of the second protective structure 52 and a portion of the third protective structure 53 are removed, exposing a portion of the first cathode structure 41, a portion of the second cathode structure 42 and a portion of the third cathode structure located above the first anode structure, the second anode structure 22 and the third anode structure 23.
[0067] The first protective structure 51, the second protective structure 52 and part of the third protective structure 53 above the anode structure can also be removed, so that the common cathode is electrically connected to the first cathode structure 41, the second cathode structure 42 and the third cathode structure 43 above the anode structure.
[0068] Preferably, the shape of the photomask can be designed to minimize the width of the etching of the first protective structure 51, the second protective structure 52, and the third protective structure 53, thereby forming a narrower channel within the protective layer. This narrower conductive channel 71 simultaneously satisfies the purpose of connecting the common cathode layer 7 to the cathode structure. Thus, while ensuring reliable conduction of the common cathode layer 7, it also protects the organic light-emitting layer above the anode structure, preventing the etching from significantly impacting the underlying organic light-emitting layer.
[0069] Optionally, in this embodiment, after step S11, the method further includes: S12: Fabricate a common cathode layer 7 such that the common cathode layer 7 covers the exposed portions of the first cathode structure 41, the second cathode structure 42, and the third cathode structure 43.
[0070] A common cathode layer 7 is fabricated to cover the exposed portions of the first cathode structure 41, the second cathode structure 42, and the third cathode structure 43, enabling electrical connection between the common cathode layer 7 and each pixel. Finally, an encapsulation layer 9 is placed on top of the common cathode layer 7 to complete the fabrication of the pixel unit. Figure 20 As shown.
[0071] according to Figure 20 As can be seen from the pixel unit shown, since there is no organic light-emitting layer above the pixel definition structure 1, the depth of the gap between two adjacent pixel areas is reduced, making it easier for the common cathode layer 7 to form a continuous cathode layer at this position, thereby improving the continuity and conductivity reliability of the common cathode layer 7.
[0072] Optionally, in this embodiment, step S2 includes: The pixel definition layer 11 and the first stripping sacrificial layer 611 are patterned to obtain a plurality of strip pixel definition structures 1 arranged at intervals along the first direction, such that an exposed channel 13 without the pixel definition layer 11 is formed between adjacent anode structures in the second direction. The first direction and the second direction are both parallel to the substrate 10 and perpendicular to each other.
[0073] The first cathode structure 41, the second cathode structure 42, and the third cathode structure 43 all cover the anode structure and the exposure channel 13, and are electrically connected to the outer cathode ring 101 through the exposure channel 13.
[0074] By manufacturing a strip-shaped pixel definition structure 1, the first cathode structure 41, the second cathode structure 42 and the third cathode structure 43 all cover the anode structure and the exposed channel 13, and are electrically connected to the peripheral cathode ring 101 through the exposed channel 13.
[0075] Specifically, the initial pixel definition layer 11 is patterned to obtain a plurality of strip-shaped pixel definition structures 1 arranged at intervals along the first direction. These strip-shaped pixel definition structures 1 are used to separate the anode structures arranged at intervals along the first direction. Figure 21 The first cathode structure 41, the second cathode structure 42, and the third cathode structure 43 cover the adjacent anode structure and the exposed channel 13 along the second direction, and both ends of the cathode structures are connected to the outer cathode ring 101, respectively. Figure 22-23 shown Figure 21 Longitudinal and transverse cross-sectional views.
[0076] A PDL is set in one direction, and a continuous cathode structure is formed in the direction where there is no PDL. See Figure 22 The two ends of the cathode structure are connected to the cathode ring 101 respectively, so as to achieve a reliable conduction effect on the cathode structure. In this way, only three exposure etching processes are needed to prepare real RGB products.
[0077] The present invention also provides a pixel unit, wherein the display panel is manufactured by a method for manufacturing the pixel unit, comprising: A substrate 10 is provided with an anode layer and a pixel definition structure 1. The anode layer includes a first anode structure 21, a second anode structure 22 and a third anode structure 23. The first organic light-emitting structure 31, the first cathode structure 41, and the first protective structure 51 are located on the first anode structure 21.
[0078] Optionally, in this embodiment, it further includes: The second organic light-emitting structure 32, the second cathode structure 42, and the second protective structure 52 are located on the second anode structure 22; The third organic light-emitting structure 33, the third cathode structure 43, and the third protective structure 53 are located on the third anode structure 23.
[0079] Optionally, in this embodiment, the pixel definition structure 1 is provided with a pixel opening 12, which corresponds to the first anode structure 21, the second anode structure 22 and the third anode structure 23 respectively. Conductive channels 71 are respectively provided on the surfaces of the first protective structure 51, the second protective structure 52 and the third protective structure 53. The first cathode structure 41, the second cathode structure 42 and the third cathode structure 43 expose cathode connection areas 72 through the conductive channels 71. The common cathode layer 7 is electrically connected to the first cathode structure 41, the second cathode structure 42 and the third cathode structure 43 through the cathode connection areas 72.
[0080] Optionally, in this embodiment, the conductive channel 71 is located above the pixel definition structure 1.
[0081] Alternatively, in this embodiment, the conductive channel 71 is located above the anode layer.
[0082] Optionally, in this embodiment, a plurality of pixel definition structures 1 are provided, and the plurality of pixel definition structures 1 are arranged at intervals along a first direction, forming an exposure channel 13 between adjacent anode structures in a second direction; The first cathode structure 41, the second cathode structure 42, and the third cathode structure 43 all cover the anode structure and the exposure channel 13, and are electrically connected to the outer cathode ring 101 through the exposure channel 13.
[0083] Both the first and second directions are parallel to the base 10 and perpendicular to each other.
[0084] The present invention also provides a display panel comprising an array of pixel units.
[0085] The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the protection scope of the present invention.
[0086] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not describe the various possible combinations separately.
[0087] Furthermore, various different embodiments of the present invention can be combined in any way, as long as they do not violate the spirit of the present invention, they should also be regarded as the content disclosed by the present invention.
Claims
1. A method for manufacturing a pixel unit, characterized in that, Includes the following steps: S1: An anode layer is fabricated on one side of the substrate, such that the anode layer includes a first anode structure located in a first pixel region, a second anode structure located in a second pixel region, and a third anode structure located in a third pixel region; S2. A pixel definition layer and a first stripping sacrificial layer are sequentially fabricated on the substrate obtained in S1. The pixel definition layer and the first stripping sacrificial layer on the anode layer are removed to obtain a pixel definition structure and a first stripping sacrificial structure covering the pixel definition structure. S3. On the substrate obtained in S2, an initial first organic light-emitting layer is fabricated, and the first stripping sacrificial structure is peeled off to obtain an intermediate first organic light-emitting layer located on the first anode structure, the second anode structure and the third anode structure. S4. On the substrate obtained in S3, a first cathode layer and a first protective layer are sequentially fabricated. The first protective layer, the first cathode layer and the intermediate first organic light-emitting layer located in the second pixel area and the third pixel area are removed to obtain a first organic light-emitting structure, a first cathode structure and a first protective structure located in the first pixel area.
2. The method for manufacturing a pixel unit according to claim 1, characterized in that, Also includes: S5. Fabricate a second stripping sacrificial layer on the substrate obtained in S4, remove the second stripping sacrificial layer on the anode layer, and obtain a second stripping sacrificial structure located on the pixel definition structure. S6. Fabricate an initial second organic light-emitting layer on the substrate, peel off the second peeling sacrificial structure, and obtain an intermediate second organic light-emitting layer located on the anode layer; S7. Sequentially fabricate a second cathode layer and a second protective layer on the substrate, and remove the second protective layer, the second cathode layer and the intermediate second organic light-emitting layer located in the first pixel area and the third pixel area to obtain a second organic light-emitting structure, a second cathode structure and a second protective structure located in the second pixel area.
3. The method for manufacturing a pixel unit according to claim 2, characterized in that, Also includes: S8. Fabricate a third stripping sacrificial layer on the substrate obtained in S7, remove the third stripping sacrificial layer on the anode layer, and obtain a third stripping sacrificial structure located on the pixel definition structure. S9. Fabricate an initial third organic light-emitting layer on the substrate obtained in S8, and peel off the third peeling sacrificial structure to obtain an intermediate third organic light-emitting layer located on the anode layer. S10. On the substrate obtained in S9, a third cathode layer and a third protective layer are sequentially fabricated. The third protective layer, the third cathode layer and the intermediate third organic light-emitting layer located in the first pixel region and the second pixel region are removed to obtain a third organic light-emitting structure, a third cathode structure and a third protective structure located in the third pixel region.
4. The method for manufacturing a pixel unit according to claim 3, characterized in that, Step S2 includes: The pixel definition layer and the first stripping sacrificial layer are patterned to obtain pixel openings corresponding to the first anode structure, the second anode structure, and the third anode structure.
5. The method for manufacturing a pixel unit according to claim 4, characterized in that, Following step S10, the method further includes: S11: Under the mask of the mask, remove part of the first protective structure, part of the second protective structure and part of the third protective structure to expose part of the first cathode structure, part of the second cathode structure and part of the third cathode structure located above the pixel definition structure.
6. The method for manufacturing a pixel unit according to claim 4, characterized in that, Following step S10, the method further includes: S11: Under the mask of the photomask, remove part of the first protective structure, part of the second protective structure and part of the third protective structure to expose part of the first cathode structure, part of the second cathode structure and part of the third cathode structure located above the first anode structure, the second anode structure and the third anode structure.
7. The method for manufacturing a pixel unit according to claim 5 or 6, characterized in that, Following step S11, the following is also included: S12: Fabricate a common cathode layer such that the common cathode layer covers the exposed portions of the first cathode structure, the second cathode structure, and the third cathode structure.
8. The method for manufacturing a pixel unit according to claim 3, characterized in that, Step S2 includes: The pixel definition layer and the first stripping sacrificial layer are patterned to obtain a plurality of strip-shaped pixel definition structures spaced apart along the first direction, such that an exposed channel without a pixel definition layer is formed between adjacent anode structures in the second direction. The first direction and the second direction are both parallel to the substrate and perpendicular to each other.
9. The method for manufacturing a pixel unit according to claim 8, characterized in that, The first cathode structure, the second cathode structure, and the third cathode structure all cover the anode structure and the exposure channel, and are electrically connected to the peripheral cathode ring through the exposure channel.
10. A pixel unit, characterized in that, The pixel unit is manufactured by the method described in any one of claims 1-9, comprising: A substrate, wherein an anode layer and a pixel definition structure are disposed on the substrate, the anode layer including a first anode structure, a second anode structure and a third anode structure; The first organic light-emitting structure, the first cathode structure, and the first protective structure are located on the first anode structure.
11. The pixel unit according to claim 10, characterized in that, Also includes: The second organic light-emitting structure, the second cathode structure, and the second protective structure are located on the second anode structure; The third organic light-emitting structure, the third cathode structure, and the third protective structure are located on the third anode structure.
12. The pixel unit according to claim 11, characterized in that, The pixel definition structure is provided with pixel openings, which correspond to the first anode structure, the second anode structure, and the third anode structure, respectively. The surfaces of the first protective structure, the second protective structure, and the third protective structure are respectively provided with conductive channels. The first cathode structure, the second cathode structure, and the third cathode structure expose cathode connection areas through the conductive channels. The common cathode layer is electrically connected to the first cathode structure, the second cathode structure, and the third cathode structure through the cathode connection areas.
13. The pixel unit according to claim 12, characterized in that, The conductive channel is located above the pixel definition structure.
14. The pixel unit according to claim 12, characterized in that, The conductive channel is located above the anode layer.
15. The pixel unit according to claim 11, characterized in that, Multiple pixel definition structures are provided, and the multiple pixel definition structures are arranged at intervals along the first direction, forming an exposure channel between adjacent anode structures in the second direction; The first cathode structure, the second cathode structure, and the third cathode structure all cover the anode structure and the exposure channel, and are electrically connected to the peripheral cathode ring through the exposure channel; The first direction and the second direction are both parallel to the base and perpendicular to each other.
16. A display panel, characterized in that, Including pixel units arranged in an array as described in any one of claims 10-15.