Indication device
The display device enhances moisture resistance by using a rib and partition wall structure with inorganic layers to protect the organic layer, addressing the issue of moisture-induced brightness loss and improving display quality.
Patent Information
- Application Number
- JP2023500593
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2021-02-17
- Filing Date
- 2021-12-24
- Publication Date
- 2026-01-13
- Estimated Expiration
- 2041-12-24
AI Technical Summary
Organic light-emitting diode (OLED) display devices are susceptible to moisture, which can lead to a decrease in brightness and display quality due to the low moisture resistance of organic layers.
A display device design incorporating a rib structure with a partition wall and inorganic layers to create a barrier against moisture ingress, using inorganic layers to cover the organic layer and partition walls, ensuring adhesion between these layers to prevent moisture from reaching the organic layer.
The design effectively prevents moisture from reaching the organic layer, thereby improving display quality by maintaining brightness and reducing display defects such as dark spots.
Smart Images

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Abstract
Description
[Technical Field]
[0001] FIELD An embodiment of the present invention relates to a display device. [Background technology]
[0002] In recent years, display devices that use organic light-emitting diodes (OLEDs) as display elements have been put to practical use. These display elements include a first electrode, a second electrode, and an organic layer disposed between these electrodes. The organic layer emits light in response to the voltage applied between the first and second electrodes.
[0003] Generally, organic layers have low resistance to moisture. If moisture reaches the organic layers for some reason, it can cause a decrease in the brightness of the display element when it emits light, which can lead to a decrease in display quality. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2008-135325 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-195677 Summary of the Invention [Problem to be solved by the invention]
[0005] An object of the present invention is to provide a display device capable of improving display quality. [Means for solving the problem]
[0006] A display device according to one embodiment includes a rib having an opening and an upper surface, a partition wall arranged on the upper surface of the rib, a first electrode overlapping the opening, an organic layer having a first end located on the upper surface and covering the first electrode, a second electrode having a second end located on the upper surface and covering the organic layer, a first inorganic layer arranged on the rib, and a second inorganic layer covering the partition wall, the second electrode, and the first inorganic layer. The partition wall is disposed on the first inorganic layer.At least a portion of the first inorganic layer is located between the first end and the partition wall and is in contact with the second inorganic layer. A display device according to another embodiment includes a rib having an opening and an upper surface, and a display element disposed on the upper surface of the rib. Ta a partition wall, a first electrode overlapping the opening, an organic layer having a first end portion located on the upper surface and covering the first electrode, and a second electrode having a second end portion located on the upper surface and covering the organic layer; a first inorganic layer disposed on the ribs; and a second inorganic layer covering the partition wall and the second electrode. At least a portion of the first inorganic layer is located between the first end and the partition wall and is in contact with the second inorganic layer. The partition wall is in contact with the upper surface of the rib. The first inorganic layer is located between the first end and the partition wall. The first inorganic layer has a frame shape surrounding the opening in a plan view. [Brief explanation of the drawings]
[0007] [Figure 1] FIG. 1 is a diagram showing an example of the configuration of a display device according to the first embodiment. [Figure 2] FIG. 2 is a diagram showing an example of a layout of sub-pixels according to the first embodiment. [Figure 3] FIG. 3 is a schematic cross-sectional view of the display device taken along line III-III in FIG. [Figure 4] FIG. 4 is a cross-sectional view showing an example of a layer configuration that can be applied to the organic layer according to the first embodiment. [Figure 5] FIG. 5 is a schematic plan view showing an example of a configuration applicable to the opening of the rib, the first inorganic layer, and the power supply line according to the first embodiment. [Figure 6] FIG. 6 is a schematic cross-sectional view of the display device taken along line VI-VI in FIG. [Figure 7] FIG. 7 is a schematic cross-sectional view of the display device taken along line VII-VII in FIG. [Figure 8] FIG. 8 is a schematic plan view of a first inorganic layer and a power supply line in a display device according to a second embodiment. [Figure 9] FIG. 9 is a schematic cross-sectional view of the display device taken along line IX-IX in FIG. [Figure 10] FIG. 10 is a schematic cross-sectional view of a display device according to the third embodiment. [Figure 11]FIG. 11 is a schematic cross-sectional view of a display device according to a fourth embodiment. [Figure 12] FIG. 12 is a schematic cross-sectional view of a display device according to a fifth embodiment. [Figure 13] FIG. 13 is a schematic cross-sectional view showing another example of the display device according to the fifth embodiment. [Figure 14] FIG. 14 is a schematic cross-sectional view of a display device according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION
[0008] Hereinafter, several embodiments will be described with reference to the drawings. The disclosure is merely an example, and appropriate modifications that a person skilled in the art can easily make while maintaining the gist of the invention are naturally included within the scope of the present invention. Furthermore, the drawings may be schematic in width, thickness, shape, etc., compared to the actual embodiment for clarity of explanation, but these are merely examples and are not intended to limit the interpretation of the present invention. Furthermore, in this specification and each drawing, components that perform the same or similar functions as those described above with reference to the previous drawings are designated by the same reference numerals, and redundant detailed descriptions may be omitted as appropriate.
[0009] In addition, to facilitate understanding, the drawings depict, where necessary, mutually orthogonal X, Y, and Z axes. The direction along the X axis is referred to as the first direction, the direction along the Y axis is referred to as the second direction, and the direction along the Z axis is referred to as the third direction. The plane defined by the X and Y axes is referred to as the XY plane, and the plane defined by the X and Z axes is referred to as the XZ plane. Viewing the XY plane is referred to as planar viewing. In addition, the direction toward the observer in the direction along the Z axis is referred to as the top or upper side, and the upper side is referred to as the top surface.
[0010] The display device DSP according to this embodiment is an organic electroluminescence display device having organic light-emitting diodes (OLEDs) as display elements, and can be mounted in televisions, personal computers, in-vehicle devices, tablet terminals, smartphones, mobile phone terminals, and the like.
[0011] [First embodiment] 1 is a diagram showing an example of the configuration of a display device DSP according to the first embodiment. The display device DSP has a display area DA for displaying an image and a peripheral area SA outside the display area DA, on an insulating base material 10. The base material 10 may be glass or a flexible resin film.
[0012] The display area DA includes a plurality of pixels PX arranged in a matrix in the first direction X and the second direction Y. Each pixel PX includes a plurality of subpixels SP. In one example, the pixel PX includes a red subpixel SP1, a green subpixel SP2, and a blue subpixel SP3. Note that the pixel PX may include four or more subpixels, including subpixels of other colors such as white, in addition to the above three subpixels.
[0013] The subpixel SP includes a pixel circuit 1 and a display element 20 driven by the pixel circuit 1. The pixel circuit 1 includes a pixel switch 2, a drive transistor 3, and a capacitor 4. The pixel switch 2 and the drive transistor 3 are switching elements formed of, for example, thin film transistors.
[0014] In the pixel switch 2, the gate electrode is connected to the scanning line GL. One of the source electrode and drain electrode of the pixel switch 2 is connected to the signal line SL, and the other is connected to the gate electrode of the drive transistor 3 and the capacitor 4. In the drive transistor 3, one of the source electrode and drain electrode is connected to the power supply line PL and the capacitor 4, and the other is connected to the anode of the display element 20. The cathode of the display element 20 is connected to the power supply line FL to which a common voltage is applied. Note that the configuration of the pixel circuit 1 is not limited to the example shown in the figure.
[0015] The display element 20 is an organic light-emitting diode (OLED) that functions as a light-emitting element. For example, the subpixel SP1 includes a display element that emits light corresponding to a red wavelength, the subpixel SP2 includes a display element that emits light corresponding to a green wavelength, and the subpixel SP3 includes a display element that emits light corresponding to a blue wavelength. The configuration of the display element 20 will be described later.
[0016] 2 is a diagram showing an example of the layout of subpixels SP (SP1, SP2, SP3). Here, attention is focused on four pixels PX. In each pixel PX, the subpixels SP1, SP2, SP3 are arranged in this order in the first direction X. That is, in the display area DA, a column made up of a plurality of subpixels SP1 arranged in the second direction Y, a column made up of a plurality of subpixels SP2 arranged in the second direction Y, and a column made up of a plurality of subpixels SP3 arranged in the second direction Y are arranged alternately in the first direction X.
[0017] Ribs 14 are arranged at the boundaries between the subpixels SP1, SP2, and SP3. In the example of Fig. 2, the ribs 14 are in a lattice shape having portions located between the subpixels SP adjacent to each other in the first direction X and portions located between the subpixels SP adjacent to each other in the second direction Y. The ribs 14 form openings OP in each of the subpixels SP1, SP2, and SP3.
[0018] 2, the plurality of partition walls PT include a plurality of partition walls PT1 parallel to the second direction Y and a plurality of partition walls PT2 parallel to the first direction X.
[0019] The partition wall PT1 is located between the subpixels SP1 and SP2 adjacent to each other in the first direction X, between the subpixels SP2 and SP3 adjacent to each other in the first direction X, and between the subpixels SP1 and SP3 adjacent to each other in the first direction X. In other words, the partition wall PT1 is located at the boundary between the subpixels SP of different colors.
[0020] The partition walls PT2 are located between two subpixels SP1 adjacent to each other in the second direction Y, between two subpixels SP2 adjacent to each other in the second direction Y, and between two subpixels SP3 adjacent to each other in the second direction Y. In other words, the partition walls PT2 are located at the boundaries of subpixels SP of the same color.
[0021] Figure 3 is a schematic cross-sectional view of the display device DSP taken along line III-III in Figure 2. Figure 3 mainly shows the cross-sectional structure of subpixel SP2, but subpixels SP1 and SP3 also have similar cross-sectional structures. Note that only the drive transistor 3 and display element 20 are shown as elements disposed in subpixel SP2, and other elements are not shown.
[0022] The display device DSP includes insulating layers 11, 12, and 13, a first inorganic layer 15, a second inorganic layer 16, a resin layer 17, and a third inorganic layer 18, in addition to the above-mentioned base material 10, ribs 14, partition walls PT1, and power supply lines FL.
[0023] The insulating layers 11, 12, and 13 are stacked on the base material 10 in the third direction Z. The insulating layers 11 and 12 are made of, for example, an inorganic material, and the insulating layer 13 is made of, for example, an organic material.
[0024] The driving transistor 3 includes a semiconductor layer 30 and electrodes 31, 32, and 33. The electrode 31 corresponds to a gate electrode. One of the electrodes 32 and 33 corresponds to a source electrode, and the other corresponds to a drain electrode. The semiconductor layer 30 is disposed between the substrate 10 and the insulating layer 11. The electrode 31 is disposed between the insulating layers 11 and 12. The electrodes 32 and 33 are disposed between the insulating layers 12 and 13, and are in contact with the semiconductor layer 30 through contact holes that penetrate the insulating layers 11 and 12.
[0025] The display element 20 includes a first electrode E1, an organic layer OR, and a second electrode E2. The first electrode E1 is an electrode disposed for each subpixel SP and may be referred to as a pixel electrode, a lower electrode, or an anode. The second electrode E2 is an electrode disposed in common to multiple subpixels SP and may be referred to as a common electrode, an upper electrode, or a cathode.
[0026] The ribs 14 are disposed on the insulating layer 13. The ribs 14 can be formed of an organic material. The first electrode E1 is disposed on the insulating layer 13 and overlaps with the opening OP. The peripheral edge of the first electrode E1 is covered by the ribs 14. The first electrode E1 is electrically connected to the electrode 33 through a contact hole that penetrates the insulating layer 13. The first electrode E1 is formed of a metal material. However, the first electrode E1 may be formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO), or may be a laminate of a transparent conductive material and a metal material.
[0027] The organic layer OR covers the first electrode E1 and the ribs 14. The organic layer OR is in contact with the first electrode E1 through the opening OP. A portion of the organic layer OR is located on the ribs 14.
[0028] The second electrode E2 covers the organic layer OR. The second electrode E2 is made of a metal material. However, the second electrode E2 may also be made of a transparent conductive material such as ITO or IZO.
[0029] The partition wall PT1 is disposed on the rib 14. The partition wall PT2 shown in FIG. 2 is also disposed on the rib 14. The partition walls PT1 and PT2 are formed of, for example, an organic material. The power supply line FL and the first inorganic layer 15 are disposed on the rib 14. The power supply line FL is formed of a metal material.
[0030] The second inorganic layer 16 covers the second electrode E2, the rib 14, the first inorganic layer 15, and the partition wall PT1. The resin layer 17 covers the second inorganic layer 16. The resin layer 17 is formed to be thicker than, for example, the insulating layers 11, 12, and 13, the rib 14, the second inorganic layer 16, the third inorganic layer 18, and the partition wall PT1. The third inorganic layer 18 covers the resin layer 17.
[0031] The first inorganic layer 15, the second inorganic layer 16, and the third inorganic layer 18 are formed of inorganic materials such as silicon oxide (SiOx) and silicon nitride (SiNx). The first inorganic layer 15 and the second inorganic layer 16 are preferably formed of the same inorganic material. This improves adhesion between the first inorganic layer 15 and the second inorganic layer 16. When the first inorganic layer 15, the second inorganic layer 16, and the third inorganic layer 18 are formed of the same inorganic material, the film densities and composition ratios of these inorganic layers 15, 16, and 18 may be different. Furthermore, both the first inorganic layer 15 and the second inorganic layer 16 may be formed of a silicon-based inorganic material, such as when one of the first inorganic layer 15 and the second inorganic layer 16 is silicon oxide and the other is silicon nitride. Furthermore, the first inorganic layer 15 and the second inorganic layer 16 may be formed of the same inorganic material other than a silicon-based material. Even in these cases, adhesion between the first inorganic layer 15 and the second inorganic layer 16 can be improved.
[0032] The second inorganic layer 16, the resin layer 17, and the third inorganic layer 18 function as sealing layers that protect the organic layer OR from moisture, etc. Furthermore, the second inorganic layer 16, the resin layer 17, and the third inorganic layer 18 also function as planarizing layers that planarize the unevenness caused by the ribs 14.
[0033] 4 is a cross-sectional view showing an example of a layer configuration applicable to the organic layer OR. For example, the organic layer OR includes a first functional layer F1, an emitting layer EL, and a second functional layer F2 stacked in this order from the first electrode E1 to the second electrode E2.
[0034] When the potential of the first electrode E1 is relatively higher than the potential of the second electrode E2, the first electrode E1 corresponds to the anode and the second electrode E2 corresponds to the cathode. When the potential of the second electrode E2 is relatively higher than the potential of the first electrode E1, the second electrode E2 corresponds to the anode and the first electrode E1 corresponds to the cathode.
[0035] As an example, when the first electrode E1 corresponds to an anode, the first functional layer F1 includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer, and the second functional layer F2 includes at least one of an electron transport layer, an electron injection layer, and a hole blocking layer.
[0036] When a potential difference is generated between the first electrode E1 and the second electrode E2, the emitting layer EL emits light. In this embodiment, it is assumed that the emitting layers EL included in the organic layers OR of the subpixels SP1, SP2, and SP3 all emit light of the same color (e.g., white). In this case, for example, color filters corresponding to the colors of the subpixels SP1, SP2, and SP3 may be disposed above the resin layer 17. Furthermore, layers containing quantum dots that are excited by the light emitted by the emitting layers EL to generate light of colors corresponding to the subpixels SP1, SP2, and SP3 may be disposed in the subpixels SP1, SP2, and SP3.
[0037] 5 is a schematic plan view showing an example of a configuration applicable to the opening OP, the first inorganic layer 15, and the power supply line FL. Here, a configuration corresponding to subpixels SP1, SP2, and SP3 aligned in the first direction X and other subpixels SP1, SP2, and SP3 aligned in the second direction Y with these subpixels SP1, SP2, and SP3 is shown.
[0038] 5, the first inorganic layer 15 and the power supply line FL are in the shape of a rectangular frame surrounding the opening OP. In each of the subpixels SP1, SP2, and SP3, the power supply line FL is located between the opening OP and the first inorganic layer 15.
[0039] Two first inorganic layers 15 aligned in the first direction X are connected by a connecting portion C1a. Two first inorganic layers 15 aligned in the second direction Y are connected by a connecting portion C1b. In the example of FIG. 5, the connecting portion C1a connects the centers of the two first inorganic layers 15 in the second direction Y, and the connecting portion C1b connects the centers of the two first inorganic layers 15 in the first direction X. However, the positions of the connecting portions C1a and C1b are not limited to this example. Furthermore, two first inorganic layers 15 aligned in the first direction X may be connected by multiple connecting portions C1a. Similarly, two first inorganic layers 15 aligned in the second direction Y may be connected by multiple connecting portions C1b.
[0040] Two power feeders FL arranged side by side in the first direction X are connected by a connection portion C2a. Two power feeders FL arranged side by side in the second direction Y are connected by a connection portion C2b. In the example of FIG. 5, the connection portion C2a overlaps with the connection portion C1a, and the connection portion C2b overlaps with the connection portion C1b. However, the connection portions C2a and C2b may be provided at positions that do not overlap with the connection portions C1a and C1b, respectively. Furthermore, two power feeders FL arranged side by side in the first direction X may be connected by multiple connection portions C2a, and two power feeders FL arranged side by side in the second direction Y may be connected by multiple connection portions C2b. When the connection portion C1a and the connection portion C2a overlap, it is preferable that the width of the connection portion C1a in the second direction Y is wider than the width of the connection portion C2a in the second direction Y, and the connection portion C1a entirely covers the connection portion C2a. Similarly, when the connection portion C1b and the connection portion C2b overlap, it is preferable that the width of the connection portion C1b in the first direction X is wider than the width of the connection portion C2b in the first direction X, and that the connection portion C1b entirely covers the connection portion C2b.
[0041] Some of the multiple power supply lines FL connected by the connection portions C2a and C2b extend into the peripheral area SA and are connected to wiring to which a common voltage is applied. As another example, at least one of the multiple power supply lines FL may be connected to wiring to which a common voltage is applied in the display area DA. In this case, the wiring may be disposed in any layer between the base material 10 and the insulating layer 13, and the power supply line FL may be connected to the wiring through a contact hole that penetrates at least the rib 14 and the insulating layer 13.
[0042] Fig. 6 is a schematic cross-sectional view of the display device DSP taken along line VI-VI in Fig. 5. Here, the base material 10, insulating layers 11, 12, 13, resin layer 17, and third inorganic layer 18 are omitted.
[0043] The partition wall PT1 has a first portion P1 and a second portion P2. The second portion P2 is located between the first portion P1 and the rib 14 in the third direction Z. In the example of Fig. 6, the second portion P2 is in contact with the upper surface 14a of the rib 14.
[0044] The first portion P1 has a first width W1a. The second portion P2 has a second width W2a. The second width W2a is smaller than the first width W1 (W1a>W2a).
[0045] In the example of FIG. 6, the pair of side surfaces SF1 of the first portion P1 are inclined so that the distance between these side surfaces SF1 decreases from the upper end to the lower end of the first portion P1. That is, the width of the first portion P1 is not constant in the third direction Z. The first width W1a corresponds to the maximum width of the first portion P1, and in the example shown, it is the width of the upper end of the first portion P1. The pair of side surfaces SF1 may be parallel to the third direction Z. The pair of side surfaces SF1 may also be inclined so that the distance between these side surfaces SF1 increases from the upper end to the lower end of the first portion P1. In the example of FIG. 6, the pair of side surfaces SF2 of the second portion P2 are parallel to the third direction Z. However, the pair of side surfaces SF2 may be inclined with respect to the third direction Z.
[0046] The first portion P1 has a pair of lower surfaces BF connecting the side surface SF1 and the side surface SF2. These lower surfaces BF face the upper surface 14a of the rib 14. The shape of the partition wall PT1 having the first portion P1 and the second portion P2 having such shapes can be called, for example, an overhang shape.
[0047] An organic layer ORa and a conductive layer E2a covering the organic layer ORa are disposed on the partition wall PT1 (first portion P1). The organic layer ORa is formed of the same material as the organic layer OR. The conductive layer E2a is formed of the same material as the second electrode E2. The organic layer ORa is spaced apart from the organic layers OR disposed in the subpixels SP1 and SP2. The conductive layer E2a is spaced apart from the second electrodes E2 disposed in the subpixels SP1 and SP2.
[0048] The organic layer OR and the second electrode E2 are formed over the entire display area DA by, for example, vacuum deposition. At this time, material from a deposition source adheres to the upper surface of the partition wall PT1, forming the organic layer ORa and the conductive layer E2a. On the other hand, the material from the deposition source is less likely to adhere to the side surfaces SF1 and SF2. This separates the organic layer OR from the organic layer ORa, and separates the second electrode E2 from the conductive layer E2a.
[0049] The organic layer OR has a first end ED1 on the upper surface 14a of the rib 14. The second electrode E2 has a second end ED2 on the upper surface 14a. Both the first end ED1 and the second end ED2 are spaced apart from the second portion P2. The second end ED2 is located between the first end ED1 and the second portion P2 in the first direction X. The first end ED1 is covered by the second electrode E2.
[0050] The first inorganic layer 15 is located on the upper surface 14a between the first end ED1 and the second portion P2. The first inorganic layer 15 is in contact with the upper surface 14a. The second portion P2 is located between the first inorganic layer 15 of the subpixel SP1 and the first inorganic layer 15 of the subpixel SP2 and is spaced apart from these first inorganic layers 15.
[0051] The power supply line FL is located on the upper surface 14a between the first end ED1 and the first inorganic layer 15. The second end ED2 is located between the first end ED1 and the first inorganic layer 15. The second electrode E2 is in contact with the power supply line FL. In the example of FIG. 6, the entire power supply line FL is covered with the second electrode E2, and the second end ED2 is located between the power supply line FL and the first inorganic layer 15. However, a portion of the power supply line FL may not be covered by the second electrode E2.
[0052] The second inorganic layer 16 is formed after the second electrode E2 is formed by a method such as chemical vapor deposition (CVD), which has high film-forming properties on wall portions such as the side surfaces SF1 and SF2. In the example of FIG. 6, the second inorganic layer 16 covers the second electrode E2, the first inorganic layer 15, and the partition wall PT1. More specifically, the second inorganic layer 16 covers the side surfaces SF1 and SF2 and the conductive layer E2a. The second inorganic layer 16 may not cover a portion of the side surfaces SF1 and SF2.
[0053] 7 is a schematic cross-sectional view of the display device DSP taken along line VII-VII in FIG. 5. This cross-section includes the connection portions C1a and C2a. The connection portion C1a and the first inorganic layer 15 are integrally formed of the same material. The connection portion C2a and the power supply line FL are integrally formed of the same material.
[0054] The connection portion C2a is disposed on the upper surface 14a of the rib 14. The connection portion C1a is disposed on the connection portion C2a. At this cross-sectional position, the first inorganic layer 15 is also disposed on the connection portion C2a, and further, the second portion P2 of the partition wall PT1 is disposed on the connection portion C1a.
[0055] 6 and 7 show the structure near the boundary between subpixels SP1 and SP2, but similar structures can also be applied to the boundary between subpixels SP2 and SP3 and the boundary between subpixels SP1 and SP3. The partition wall PT2 shown in Fig. 2 can have the same shape as the partition wall PT1. The structures shown in Fig. 6 and 7 can also be applied to the cross-sectional structures near the boundary between two subpixels SP1 aligned in the second direction Y, near the boundary between two subpixels SP2 aligned in the second direction Y, and near the boundary between two subpixels SP3 aligned in the second direction Y.
[0056] When the second inorganic layer 16 is formed by vapor deposition, an inorganic layer grows on one surface near a corner formed by two surfaces that form a large angle, and an inorganic layer also grows on the other surface. When these inorganic layers are close to each other, the inflow of gas into the area between them is suppressed, and crevice-like voids (gaps) may form. Because the resin layer 17 (see Figure 3) is also unlikely to enter these voids, air may remain in the voids.
[0057] 6 and 7, voids V are formed near the base of the second portion P2. Voids V are also formed near the corners of the side surface SF2 and the bottom surface BF. Generally, the organic layer OR has low resistance to moisture. Therefore, if moisture contained in the atmosphere of these voids V reaches the organic layer OR through the interface between the rib 14 and the second electrode E2, it may cause display defects such as a decrease in brightness of the display element 20 (the occurrence of dark spots).
[0058] In contrast, in this embodiment, the first inorganic layer 15 is disposed between the first end ED1 of the organic layer OR and the partition wall PT1, and this first inorganic layer 15 is in contact with the upper surface 14a and the second inorganic layer 16. Since the first inorganic layer 15 and the second inorganic layer 16, both of which are made of inorganic materials, have good adhesion, it is possible to prevent moisture from reaching the organic layer OR from the void V. This makes it possible to improve the display quality of the display device DSP.
[0059] Although the effects of this embodiment have been described based on the cross section including the partition wall PT1 as in FIGS. 6 and 7, the same effects can also be obtained in the vicinity of the partition wall PT2.
[0060] Hereinafter, the display device DSP according to the second to sixth embodiments will be described. For configurations not specifically mentioned in each embodiment, the same configurations as those in the preceding embodiments can be applied.
[0061] [Second embodiment] 8 is a schematic plan view of the first inorganic layer 15 and the power supply line FL in the display device DSP according to the second embodiment. In this embodiment, the first inorganic layer 15 and the power supply line FL are in a lattice shape having portions located between subpixels SP (SP1, SP2, SP3) adjacent to each other in the first direction X and portions located between subpixels SP adjacent to each other in the second direction Y. The first inorganic layer 15 forms an opening OPa in each of the subpixels SP1, SP2, SP3. The power supply line FL forms an opening OPb in each of the subpixels SP1, SP2, SP3.
[0062] The opening OP is located within the opening OPb. The opening OPb is located within the opening OPa. That is, the width of the power supply line FL in the first direction X is larger than the width of the first inorganic layer 15 in the first direction X. Furthermore, the width of the power supply line FL in the second direction Y is larger than the width of the first inorganic layer 15 in the second direction Y.
[0063] Fig. 9 is a schematic cross-sectional view of the display device DSP taken along line IX-IX in Fig. 8. The power supply lines FL are disposed on the upper surfaces 14a of the ribs 14. The first inorganic layer 15 is disposed on the power supply lines FL. The second portions P2 of the partition walls PT1 are disposed on the first inorganic layer 15.
[0064] In the first direction X, the first inorganic layer 15 is located between the second end ED2 of the second electrode E2 of the subpixel SP1 and the second end ED2 of the second electrode E2 of the subpixel SP2. In the first direction X, the power supply line FL is located between the first end ED1 of the organic layer OR of the subpixel SP1 and the first end ED1 of the organic layer OR of the subpixel SP2.
[0065] The first inorganic layer 15 covers a portion of the power supply line FL. Both ends of the power supply line FL in the first direction X are exposed from the first inorganic layer 15. In each of the subpixels SP1 and SP2, the second electrode E2 is in contact with the portion of the power supply line FL that is exposed from the first inorganic layer 15. In each of the subpixels SP1 and SP2, the first inorganic layer 15 is in contact with the second inorganic layer 16.
[0066] In the configuration of this embodiment, the first inorganic layer 15 is disposed around the entire periphery of the second portion P2 of the partition wall PT1, which makes it possible to increase the contact area between the first inorganic layer 15 and the second inorganic layer 16. This effectively prevents moisture from reaching the organic layer OR from the void V.
[0067] 9 shows the structure near the boundary between subpixels SP1 and SP2, but a similar structure can be applied to the vicinity of the boundary between subpixels SP2 and SP3 or the vicinity of the boundary between subpixels SP1 and SP3. The structure shown in Fig. 9 can also be applied to the cross-sectional structure near the boundary between two subpixels SP1 aligned in the second direction Y, near the boundary between two subpixels SP2 aligned in the second direction Y, and near the boundary between two subpixels SP3 aligned in the second direction Y.
[0068] [Third embodiment] Fig. 10 is a schematic cross-sectional view of a display device DSP according to a third embodiment. The cross-sectional structure shown in this figure differs from the example shown in Fig. 9 in that the first inorganic layer 15 has portions 15a that cover a pair of side surfaces SF2 of the partition wall PT1. The second inorganic layer 16 covers these portions 15a. In other words, the portions 15a are located between the side surfaces SF2 and the second inorganic layer 16.
[0069] In the example of Fig. 10, portion 15a covers the entire side surface SF2. Portion 15a may cover, for example, a lower region of side surface SF2 but not an upper region of side surface SF2. Portion 15a may also cover at least a portion of side surface SF1. Portion 15a may also cover the entire partition wall PT1.
[0070] In the present embodiment, when the first inorganic layer 15 covers at least a part of the side surface of the partition wall PT1, the first inorganic layer 15 and the second inorganic layer 16 can be brought into contact over a wider area, which can more effectively prevent moisture from reaching the organic layer OR from the void V.
[0071] 10 shows the structure near the boundary between subpixels SP1 and SP2, but a similar structure can be applied to the boundary between subpixels SP2 and SP3 or the boundary between subpixels SP1 and SP3. The structure shown in Fig. 10 can also be applied to the cross-sectional structure near the boundary between two subpixels SP1 aligned in the second direction Y, near the boundary between two subpixels SP2 aligned in the second direction Y, and near the boundary between two subpixels SP3 aligned in the second direction Y.
[0072] [Fourth embodiment] 11 is a schematic cross-sectional view of a display device DSP according to a fourth embodiment. In the example shown in this figure, the second portion P2 of the partition wall PT1 includes a power supply line FL and a first inorganic layer 15. The power supply line FL is disposed on the upper surface 14a of the rib 14. The first inorganic layer 15 is disposed on the power supply line FL. Furthermore, the first portion P1 is disposed on the first inorganic layer 15.
[0073] For example, the thickness of the power supply line FL is greater than the thickness of the second electrode E2. The power supply line FL may be formed entirely of a metal material, or may have a structure in which the surface of an insulating layer is covered with a metal material. In the example of FIG. 11, the width of the power supply line FL is the same as the width of the first inorganic layer 15. As another example, the width of the power supply line FL may be different from the width of the first inorganic layer 15. For example, if the width of the power supply line FL is greater than the width of the first inorganic layer 15, it becomes easier to connect the power supply line FL to the second electrode E2.
[0074] The second end ED2 of the second electrode E2 is in contact with the side surface of the power supply line FL (the region below the side surface SF2). In the example of Fig. 11, the second end ED2 is not in contact with the side surface of the first inorganic layer 15. The second inorganic layer 16 is in contact with the side surface of the first inorganic layer 15 (the region above the side surface SF2).
[0075] 11, a void V is formed near the corner between the side surface SF2 and the bottom surface BF. The first inorganic layer 15 and the second inorganic layer 16 are in contact with each other between the void V and the organic layer OR, so that the path of moisture from the void V to the organic layer OR can be blocked. Therefore, as in the above-described embodiments, the arrival of moisture from the void V to the organic layer OR can be effectively suppressed.
[0076] 11 shows the structure near the boundary between subpixels SP1 and SP2, but a similar structure can also be applied to the boundary between subpixels SP2 and SP3 or the boundary between subpixels SP1 and SP3. The partition wall PT2 can have the same shape as the partition wall PT1. The structure shown in FIG. 11 can also be applied to the cross-sectional structure near the boundary between two subpixels SP1 aligned in the second direction Y, near the boundary between two subpixels SP2 aligned in the second direction Y, and near the boundary between two subpixels SP3 aligned in the second direction Y.
[0077] [Fifth embodiment] Fig. 12 is a schematic cross-sectional view of a display device DSP according to a fifth embodiment. The cross-sectional structure in this figure differs from the example in Fig. 6 in the shape of the partition wall PT1. The partition wall PT1 shown in Fig. 12 has an upper part U and a lower part B. The upper part U corresponds to the widest part of the partition wall PT1, and in the example in Fig. 12, it is the upper end (upper surface) of the partition wall PT1. The lower part B corresponds to the narrowest part of the partition wall PT1, and in the example in Fig. 12, it is the lower end (lower surface) of the partition wall PT1.
[0078] The upper portion U has a first width W1b. The lower portion B has a second width W2b that is smaller than the first width W1b (W1b>W2b). A pair of side surfaces SF of the partition wall PT1 are inclined so that the distance between these side surfaces SF becomes smaller from the upper portion U to the lower portion B. Such a shape of the partition wall PT1 can be called an inverse tapered shape.
[0079] Even when the partition wall PT1 has such a shape, the organic layer OR and the second electrode E2 can be separated between the subpixels SP1 and SP2. On the upper portion U, the organic layer ORa and the conductive layer E2a are formed as in the example of FIG.
[0080] The shapes and positions of the first inorganic layer 15, the power supply line FL, the second electrode E2, and the organic layer OR are the same as those in the example of Fig. 6. The second inorganic layer 16 covers the second electrode E2 and the first inorganic layer 15, as well as the side surface SF and the conductive layer E2a.
[0081] 13 is a schematic cross-sectional view showing another example of the display device DSP according to the fifth embodiment. As in the example of FIG. 9, a wide power supply line FL is arranged on the upper surface 14a of the rib 14, a first inorganic layer 15 is arranged on the power supply line FL, and a partition wall PT1 is arranged on the first inorganic layer 15.
[0082] In each of the subpixels SP1 and SP2, the second electrode E2 is in contact with a portion of the power supply line FL that is exposed from the first inorganic layer 15. In each of the subpixels SP1 and SP2, the first inorganic layer 15 is in contact with the second inorganic layer 16. The shape of the partition wall PT1 is the same as in the example of FIG. 12. In the example of FIG. 13, the first inorganic layer 15 may cover at least a portion of the side surface SF.
[0083] 12 and 13, a void V may be formed near the base of the partition wall PT1. Even in this case, the first inorganic layer 15 and the second inorganic layer 16 are in close contact with each other, so that moisture can be prevented from reaching the organic layer OR from the void V.
[0084] 12 and 13 show the structure near the boundary between subpixels SP1 and SP2, but a similar structure can also be applied to the boundary between subpixels SP2 and SP3 or the boundary between subpixels SP1 and SP3. The partition wall PT2 can have the same shape as the partition wall PT1. The structures shown in FIGS. 12 and 13 can also be applied to the cross-sectional structures near the boundary between two subpixels SP1 aligned in the second direction Y, near the boundary between two subpixels SP2 aligned in the second direction Y, and near the boundary between two subpixels SP3 aligned in the second direction Y.
[0085] [Sixth embodiment] In the first to fifth embodiments described above, it is assumed that the emitting layers EL included in the organic layers OR of the subpixels SP1, SP2, and SP3 emit light of the same color. In the present embodiment, it is assumed that the emitting layers EL included in the organic layers OR of the subpixels SP1, SP2, and SP3 emit light of different colors.
[0086] 14 is a schematic cross-sectional view of a display device DSP according to a sixth embodiment. While this figure shows the structure of the boundary between subpixels SP1 and SP2, a similar structure can also be applied to the boundary between subpixels SP2 and SP3 or the boundary between subpixels SP1 and SP3. The shape of the partition wall PT1 shown in FIG. 14 is the same as that of the example in FIG. 6.
[0087] In the example of Fig. 14, an organic layer OR1 is disposed in the subpixel SP1, and an organic layer OR2 is disposed in the subpixel SP2. The organic layer OR1 includes an emitting layer EL that emits, for example, red light. The organic layer OR2 includes an emitting layer EL that emits, for example, green light. Although not shown in the cross section of Fig. 14, the organic layer OR disposed in the subpixel SP3 includes an emitting layer EL that emits blue light.
[0088] The organic layer OR1 covers the first electrode E1 of the subpixel SP1 through the opening OP and also covers a part of the region of the rib 14 that is closer to the subpixel SP1 than the partition wall PT1. The organic layer OR2 covers the first electrode E1 of the subpixel SP2 through the opening OP and also covers a part of the region of the rib 14 that is closer to the subpixel SP2 than the partition wall PT1.
[0089] Organic layers OR1a and OR2a and a conductive layer E2a covering the organic layers OR1a and OR2a are arranged on the partition wall PT1. The organic layer OR1a is made of the same material as the organic layer OR1. The organic layer OR2a is made of the same material as the organic layer OR2. The conductive layer E2a is made of the same material as the second electrode E2. The organic layer OR1a is spaced apart from the organic layer OR1. The organic layer OR2a is spaced apart from the organic layer OR2. In the example of FIG. 14, a portion of the organic layer OR1a is covered by the organic layer OR2a.
[0090] The organic layer OR1 is formed by vacuum deposition using a mask with an opening in the shape of the subpixel SP1. At this time, material from a deposition source is deposited on the upper surface of the partition wall PT1, thereby forming the organic layer OR1a. After the formation of the organic layer OR1, the organic layer OR2 is formed by vacuum deposition using a mask with an opening in the shape of the subpixel SP2. At this time, material from a deposition source is deposited on the upper surface of the partition wall PT1, thereby forming the organic layer OR2a. The configuration of this embodiment can be applied to any of the above-described embodiments.
[0091] In each of the above embodiments, at least a portion of the first inorganic layer 15 is located between the first end portion ED1 and the partition wall PT1 (or the partition wall PT2) and is in contact with the second inorganic layer 16. This provides a common effect of suppressing moisture from reaching the organic layer OR from the void V.
[0092] In each embodiment, the partition wall PT1 may be formed of an inorganic material, which improves the adhesion between the second inorganic layer 16 and the partition wall PT1 and more effectively prevents moisture from reaching the organic layer OR.
[0093] 2, partition walls PT1 and PT2 are arranged at the boundaries between the subpixels SP1, SP2, and SP3, which separate the organic layers OR arranged in the subpixels SP1, SP2, and SP3, as well as the second electrodes E2 arranged in the subpixels SP1, SP2, and SP3, thereby suppressing crosstalk between adjacent subpixels SP.
[0094] Since crosstalk between subpixels SP of the same color has little effect on display quality, the partition wall PT2 does not need to be provided. In this case, the organic layers OR of subpixels SP of the same color aligned in the second direction Y are connected. Similarly, the second electrodes E2 of subpixels SP of the same color aligned in the second direction Y are connected.
[0095] All display devices that can be implemented by a person skilled in the art by appropriately modifying the design based on the display devices described above as embodiments of the present invention also fall within the scope of the present invention as long as they include the gist of the present invention.
[0096] Within the scope of the concept of the present invention, a person skilled in the art may conceive of various modifications, and these modifications are also understood to fall within the scope of the present invention. For example, even if a person skilled in the art appropriately adds or deletes components or modifies the design of the above-described embodiment, or adds or omits steps or modifies conditions, these modifications are also included within the scope of the present invention as long as they maintain the gist of the present invention.
[0097] Furthermore, with regard to other effects brought about by the aspects described in the above embodiments, those that are clear from the description in this specification or that can be appropriately thought of by a person skilled in the art are naturally understood to be brought about by the present invention. [Explanation of symbols]
[0098] DSP...display device, PX...pixel, SP...subpixel, E1...first electrode, E2...second electrode, OR...organic layer, PT1, PT2...partition wall, FL...feeder line, 1...pixel circuit, 14...rib, 15...first inorganic layer, 16...second inorganic layer.
Claims
1. a rib having an opening and an upper surface; A partition wall disposed on an upper surface of the rib; a first electrode overlapping the opening; an organic layer having a first end located on the top surface and covering the first electrode; a second electrode having a second end located on the top surface and covering the organic layer; a first inorganic layer disposed on the ribs; a second inorganic layer covering the partition wall, the second electrode, and the first inorganic layer, the partition wall is disposed on the first inorganic layer, At least a portion of the first inorganic layer is located between the first end and the partition wall and is in contact with the second inorganic layer. Display device.
2. A rib having an opening and an upper surface; A partition wall disposed on an upper surface of the rib; a first electrode overlapping the opening; an organic layer having a first end located on the top surface and covering the first electrode; a second electrode having a second end located on the top surface and covering the organic layer; a first inorganic layer disposed on the ribs; a second inorganic layer covering the partition wall, the second electrode, and the first inorganic layer, at least a portion of the first inorganic layer is located between the first end and the partition wall and is in contact with the second inorganic layer; the partition wall contacts the upper surface of the rib; the first inorganic layer is located between the first end and the partition wall, the first inorganic layer has a frame shape surrounding the opening in a plan view; Display device.
3. the second end is located between the first end and the first inorganic layer; 3. The display device according to claim 1 or 2.
4. The partition has a side surface, the second inorganic layer covers at least a portion of the side surface; 3. The display device according to claim 1 or 2.
5. a portion of the first inorganic layer is located between the side surface and the second inorganic layer; The display device according to claim 4 .
6. The partition wall is a first portion having a first width; a second portion having a second width smaller than the first width; and The second portion is located between the first portion and the rib.
3. The display device according to claim 1 or 2.
7. further comprising a power feed line disposed on the rib; the second electrode is in contact with the power supply line; 3. The display device according to claim 1 or 2.
8. At least a portion of the power supply line is located on the upper surface of the rib between the first inorganic layer and the first end portion. The display device according to claim 7 .
9. the power supply line has a shape that surrounds the opening in a plan view; The display device according to claim 7 .
10. At least a portion of the first inorganic layer covers a portion of the power supply line. The display device according to claim 7 .
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